MikeC
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| (Admin) |
| Sat Aug 21 2010 09:26 PM |
Recurve is the Name of the Game
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1:00PM EDT Update - Thursday, 26 August 2010
97L is now being tracked, this is the wave east of Earl, and has a chance to form tomorrow or over the weekend. Odds favor this recurving as well, but has even less confidence than Earl.
7:00AM EDT Update - Thursday, 26 August 2010
There are two active storms in the Atlantic this morning. Hurricane Danielle, which is recurving rather abruptly, and looks like it will miss Bermuda comfortably to the east. Danielle has another window to strengthen tomorrow into Saturday, where it still may reach major status.
Tropical Storm Earl is moving generally west northwest right now. Odds are increasing that it will recurve and miss the Caribbean islands as the weakness between 55 and 60 degrees west looks to be maintained throughout the week. This recurving is quit normal for cape Verde systems. Bermuda may have to watch Earl later, but odds favor it being missed as well. If anything changes we'll note it.
(11 AM Mini Earl Update): The hurricane center mentions a point about Earl (and Danielle) at the 11AM discussion, basically saying if Danielle recurves faster and or more abruptly than forecast, it could give a window for the ridge to reform near earl, keeping it a bit further west than the current track, which would possibly bring the Eastern Caribbean back in play. Odds are against it, but if Earl's forecasted path were to change, that would be one of the reasons why, and something to watch for.
Beyond that, the pattern probably holds into the first part of September, so odds are the wave emerging from the African coast will recurve as well around the same place. But that far out becomes a bit more uncertain. It is possible we'll have three storms to track by the end of the weekend.
The good news is that the recurve pattern looks to last into perhaps the first week of September. But unfortunately after that the pattern may start to change. However, it's still important to be vigilant for anything that develops closer to land is more of a risk, but there is nothing imminent.
The only affect along the US from these systems will be slightly higher surf, which could cause some swells, large waves and rip currents in some areas.
The area in the Gulf missed its chance to develop and will just bring some rain to Texas.
{{StormLinks|Danielle|06|6|2010|1|Danielle}}
{{StormLinks|Earl|07|7|2010|2|Earl}}
* Skeetobite hasn't updated 97L yet, actual system is off the coast of Africa *
{{StormLinks|97L|97|8|2010|3|97L}}
5:00PM EDT Update - Wednesday, 25 August 2010
Tropical Storm Earl has formed in the East Atlantic, it is forecast to become a hurricane by Friday. Odds currently favor Earl going out to sea, but the odds are not as solid as they were for Danielle. Those in the Eastern Caribbean islands will want to watch for any changes in the forecast track.
8:00AM EDT Update - Wednesday, 25 August 2010
96L appears to be reaching tropical Depression status this morning on visible satellite imagery and likely will begin advisories on Tropical Depression 7 at 11 AM EDT. Most likely forecast track for it takes it mostly west, then curves north and out to sea well before the Caribbean.
6:30AM EDT Update - Wednesday, 25 August 2010
Hurricane Danielle has maintained itself well overnight and has a chance to strengthen a bit more after a day or two when the upper level low currently negatively affecting Danielle moves more southwesterly.
Track wise, odds still favor no direct impact to land, however Bermuda is in the cone and should watch, but what's most likely is that it should pass enough to the east to avoid the worst of it. Still those in Bermuda should watch closely for any changes.
Model runs that showed a more westerly move last night have moved back to the east, and some much further to the east.
The area behind Danielle (96L) has not yet developed, but still has a chance today to become a depression, and odds still favor it staying away from land areas.
The gulf system has a small chance to develop, but isn't very likely. If it were it wouldn't do it until Friday into the weekend and it won't have much time to strengthen if it does.
8:45PM EDT Update - Tuesday, 24 August 2010
Danielle has weakened a bit today, but is on it's way back to a hurricane tonight and likely will recover.
Odds still favor no US land impact, but Bermuda is in the western forecast cone, and may need to watch the system. Longer range forecasts are a bitty iffy, but still the highest odds keep it away from land.
The wave behind Danielle (96L) Did not develop so far today, but may later tonight or tomorrow. Odds still favor this system staying out to sea as well.
The area in the Gulf has a 10% chance to develop, but is not being tracked as an investigation currently. Odds are that it will not, but if it were it would be Friday into the weekend.
You can find long range discussions/guesses on the Gulf System Here, and the same for Danielle here (including models).
7AM EDT Update - Tuesday, 24 August 2010
Hurricane Danielle has strengthened to a category 2 hurricane overnight, but has lost the eye feature that was visible last night. It has had a bit of dry air intrusion, which may keep the storm from reaching major today. It still has a chance to later, but first Danielle may actually weaken a bit, and may never make it back up that high The forecast track (and odds) still takes it out to sea regardless of strength.
Danielle is forecast to slow forward motion and begin moving more northward. Bermuda is barely in the cone, but chances of direct effects of the system are low for there.
The wave behind Danielle, 96L, may form into a depression later today. This system has a pretty good shot at developing with a 90% chance (as of 80%). It likely won't get as strong as Danielle, but it has a chance to develop none the less. Still, the most likely outcome, currently, for track on this system keeps it out to sea, following in the wake of Danielle.
Those in the Cape Verde Islands themselves, may see some effects from 96L.
Beyond that, another wave may exit the coast of Africa, and that one has a chance to stay further south and west. Those may be worth watching later this week into next week. And there is also possibility something in the Gulf could form closer to home late this weekend into next week, but there is nothing solid there.
The tropics will likely be busy over the next few weeks, so be prepared.
5PM EDT Update - Monday, 23 August 2010
Danielle has become a hurricane, the second of 2010 for the Atlantic. The forecast track keeps it far out to sea from the Caribbean and United States. It is likely to undergo rapid intensification and become this year's first major hurricane. Which, thankfully, will stay far away from land.
Behind Danielle is another tropical wave being watched that could form over the next few days, this system will likely follow Danielle out to sea.
In short, the tropics are starting to heat up again, but there is nothing approaching any land.
2PM EDT Update - Monday, 23 August 2010
Danielle appears on it's way to becoming a hurricane by tonight or tomorrow, but odds are it will stay out to sea. Danielle is likely to become this year's first major hurricane, but thankfully well away from any land areas.
Behind Danielle is another system, 96L which also has the potential to develop this week, and may do so tomorrow or Wednesday. It has a 40% chance to develop right now, and odds are this too will stay out to sea. It likely won't become as powerful as Danielle, and Danielle may keep it from doing so.
Beyond 96L, another wave may come off Africa and form, and that one could be something to keep a close eye on.
11AM EDT Update - Monday, 23 August 2010
Although still experiencing some easterly shear, Tropical Storm Danielle continues to intensify at a steady rate and is again expected to attain hurricane strength by late tonight or early Tuesday as the shear will be relaxing this evening. After a westward trend during the night, Danielle is now moving to the west northwest and a more northwesterly track is likely tonight as the cyclone approaches a weakness in the ridge near 45W. After turning to the northwest, NHC believes that a western Atlantic ridge will force Danielle on a track more to the north northwest - which seems like a reasonable scenario, however, since the westward motion last night was not anticipated, folks in the northern Leeward Islands should continue to monitor Danielle's progress for any unexpected changes.
ED
11AM EDT Update - Sunday, 22 August 2010
The organization phase of TD6 has stalled for the moment as the system has encountered strong northeasterly shear that has displaced most of the convection to the southwest of the exposed center. Movement for the past few hours has been almost due north at about 8 knots, however, a more west northwest motion should resume later today as the system moves away from strong tropical east to northeast winds.
Both the intensification outlook and the eventual track of TD6 will require some adjustment because of the disruption and delay of the current system development and the slowdown in forward motion toward the west - both current motion and forecasted movement. A slower and less aggressive intensification process should eventually bring TD6 to hurricane strength on Wednesday. The development of a mid-Atlantic trough is now anticipated to have less influence on the future track - and that track is a little less obvious than it was yesterday.
Other systems that may influence the wind flow patterns in the Atlantic include a rather intense Upper Level Low over the southern Bahamas, another ULL near 26N 43W and a new active and slowly developing tropical wave near 12N 22W at 22/15Z. Just as rapidly as conditions changed from yesterday to today, they can change again from today to tomorrow or the next day, so stay tuned.
ED
Original Post
Tropical Depression six has formed in the Eastern Atlantic, and is forecast to become a hurricane sometime Monday. The good news is that it will stay far away from any land areas.
The system has a good chance to become the first major hurricane of the season, and may generate some minor swells along the east coast, but that will be the extent of the impact.
Outside of this, there likely won't be much else to track until mid-week.
| typhoon_tip |
| (Meteorologist) |
| Sun Aug 22 2010 03:18 PM |
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Re: Tropical Depression Six Forms in East Atlantic
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Perhaps temporary, but the low and mid level centers appear to be decoupling in recent higher resolution visible imagery.
Currently Td6 is in a moderate ENE shearing, which more than likely is the culprit for looking rather exposed during the morning hours. In about 24 to 36 hours ...assuming this system lasts that long, the depression will be moving away from this region of shear; should that be the case it will find its self in an ever improving arena for the next 2 -3 days, which would offer solid opportunity for unimpeded development.
Track guidance has shifted left to varying degrees among the global numerical models over the past 24 hours. The reason for this is understandable to me. The North Atlantic Oscillation phase is currently rising and forecast to continue to do so right out through the end of the middle and extended range (D6-10). The evolution of that would argue for strengthening subtropical ridging, particularly in the western 1/3 to 1/2 of the Atlantic Basin, not troughs digging into 50W enough to induce a quick polarward motion. The ECMWF solution from 00z last night did in fact back off on that idea from 12z yesterday.
All told this would tend to dictate a left adjustment in track guidance in future runs, barring the pattern just doesn't evolve as currently modeled to do so. Obviously, the corrective assumptions are predicated on the +NAO related substantive subtropical ridging behaving accordingly...
| WeatherNut |
| (Weather Master) |
| Sun Aug 22 2010 04:09 PM |
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Re: Tropical Depression Six Forms in East Atlantic
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The NHC in the 11am discussion seemed to imply that the decoupling was due to the disturbance to the NE of TD6. Looking at recent SAT loops that area is starting to diminish probably because it is entering the drier air and cooler water. I wonder how much longer this influence will remain, or if this is mostly due to shear
| weathernet |
| (Storm Tracker) |
| Sun Aug 22 2010 04:14 PM |
Re: Tropical Depression Six Forms in East Atlantic
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Just to "piggy-back" on the recent images of a low level vort. center decoupling; ti will be interesting to see whether this feature is simply the de-facto center that is simply going to rotate back westward and co-locate with the broader convective mid level circulation. If so, than a northerly course adjustment would have to be made by NHC. I do not think this will turn out to be the case however. Even up to early this morning, the depression center maintained an elongated N.E./S.W. appearance and still in a formative stage with regards to having a well defined center. Should the low/mid level trades continue to rapidly push the larger envelope of this system more or less towards the west in the short term, and a new low level center form underneath, than significant changes to forecast may indeed be forthcoming.
| typhoon_tip |
| (Meteorologist) |
| Sun Aug 22 2010 04:34 PM |
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Re: Tropical Depression Six Forms in East Atlantic
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I think what they were referring to was specifically the reason why the N motion in the low level vortex has taken place. By this I am assuming the disturbance NE has some lowered pressure and is causing some weakness in that vicinity, drawing the vortex polarward as an indirect influence.
It was an interesting supposition on their part, and though I do not have all the tools they do for their analysis, from here it really does appear to be shear as the primary reason for the decoupling its self. The mid and high level wind overlays clearly show 15-25kts flags incurring upon the eastern semi-circle from the E and ENE.
| MichaelA |
| (Weather Analyst) |
| Sun Aug 22 2010 07:44 PM |
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Re: Tropical Depression Six Forms in East Atlantic
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Convection has begun to flair up over the LLC again this afternoon. We'll see if it gets sheared off again.
| typhoon_tip |
| (Meteorologist) |
| Sun Aug 22 2010 09:50 PM |
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Re: Tropical Depression Six Forms in East Atlantic
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Quote:
Convection has begun to flair up over the LLC again this afternoon. We'll see if it gets sheared off again.
Still seeing shear tend to displace the convection you have noted toward the West... Although, it appears the cyclone has resumed more westerly component to it current track, which is helping to mitigate that shear to some degree. Nonetheless, it is not preventing some development from succeeding.
Danielle has been officially named as of the 5pm advisory
| MichaelA |
| (Weather Analyst) |
| Mon Aug 23 2010 12:09 AM |
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Re: Tropical Depression Six Forms in East Atlantic
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Current IR (unenhanced) sat loop shows quite a robust CDO has formed over the center. Looks like some good intensification is going on now. Very cold cloud tops on the enhanced pics.
| typhoon_tip |
| (Meteorologist) |
| Mon Aug 23 2010 01:44 AM |
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Re: Tropical Depression Six Forms in East Atlantic
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Quote:
Current IR (unenhanced) sat loop shows quite a robust CDO has formed over the center. Looks like some good intensification is going on now. Very cold cloud tops on the enhanced pics.
It appears to me that the centroid axis of the llv vortex is probably closer to the eastern edge of that impressive region of cold cloud tops.
Nonetheless ... I am in general agreement here that intensification is probably underway; one clue to that is the persistence in the CDO, or CDO-like feature. Quite perpetual and increasingly symmetric in time.
Other notable is that the motion has corrected smartly west, though in keeping with the necessitated 6-hourly mean the motion would have to be WNW for the time being.
The 18z GFS run decided to abruptly break trend, both with regard to the TC, and the entirety of the local hemispheric synoptic evolution; such continuity shifts over such huge mass fields of this nature seldom demonstrate much skill.
| typhoon_tip |
| (Meteorologist) |
| Mon Aug 23 2010 03:14 AM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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Danielle has strengthened to a 50mph tropical storm this evening.
I have noticed that the deep convective cloud pattern has taken on much more cyclonic banding more centroid to the apparent CDO or CDO-like feature that rather abruptly exploded 3 hours ago. It is not uncommon for early developing TCs to have center jumps toward regions where UVM is persisting (the reasons can get complicated).
In any case, what appeared to be a deep plume of convection perhaps displaced slightly W of the llv circulation axis earlier this evening has become more collocated with the on-going rigorous and persistent CDO of CDO-like feature.
Also, the TC is moving more W by WNW and this forward motion is a negative vector against the incursion of ENE shear, such that storm relative shear has dropped off. That is similar to sticking your hand out a window while driving at 10 mph, with a wind at your tale of 20mph - you only experience a wind differential of 10mph. The same arithmetic applies in the atmosphere, such that a TC moving W at 10 mph with easterly shear of 20mph, only experiences 10 mph of bulk shear; which is not sufficient enough in most cases to prevent strengthening.
Any deep layer convection in that vicinity would be compelled to move more W given the surrounding environmental flow. When the convection erupted closer to the center of circulation earlier this evening, the center was pulled W and is now being guided again by a better coupled lower and middle atmospheric dynamic, both of which are then guided by the mid-level steering.
John
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danielw
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| (Moderator) |
| Mon Aug 23 2010 04:00 AM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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Latest satellite imagery strongly supports Tip's analysis of the near CDO or CDO-type structure in the center of the system.
Recent images of varying enhancements are indicating a spike in the cloud tops just to the west of the central area. Probably a convective hot tower-CHT. Also noted is a small circular area just to the east of the CHT. Some slight indication of an eye-like structure using several image enhancements.
Outflow channels are seen in early stages to the northwest and along the lower periphery of the system. Near and along the ITCZ.
Current tropical forecast points indicate the CHTs are nearly one degree south of the 23/ 12Z position. This would take the system on a more West or WNW track as Tip stated above. Still plenty of room for the storm to turn back on track.
Is the lack of separation from the ITCZ prolonging the westward track?
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MikeC
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| (Admin) |
| Mon Aug 23 2010 03:35 PM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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It's important to note that the track forecast Danielle's apparent westward jog was due to a recenter (with new microwave imagery) and not to more westerly movement. I think it has a good shot at becoming a major, but odds highly favor it moving north and out to sea well before any land areas.
The area in the Gulf needs a lot more time for development, and the area east of Danielle is going to face a rough time developing until later in the week, if it does at all. It has a 40% chance or so.
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Ed Dunham
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| (Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)) |
| Mon Aug 23 2010 08:13 PM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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Actually in a way you were both correct. There was a recenter at 09Z, but from 09Z till 12Z the latitude was unchanged at 14.8N - and Danielle moved west at 20mph during those three hours.
ED
| typhoon_tip |
| (Meteorologist) |
| Tue Aug 24 2010 01:20 AM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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Quote:
Actually in a way you were both correct. There was a recenter at 09Z, but from 09Z till 12Z the latitude was unchanged at 14.8N - and Danielle moved west at 20mph during those three hours.
ED
Thanks Ed ... Yes, I noted that behavior too but figured it was a protracted minor issue to get into it...
I am actually interesting (somewhat) in the fact that the guidance would have had this moving WNW by now and to the best of my ability I see a near straight west motion over the last 6 hours. 6 hours ago the perceived center was between the 15th and 16th parallels, and that is still where it is now.
Probably this is a system destined to eye candy and nothing more. The only other solution I can imagine is if the weakness somehow proves inadequate to pull it up, then the subtropical ridge amplification associated withe MA/NE heat wave later in the weekend would pin it into the SW Atlantic Basin as a drifter.
System behind this one is flared higher interest at NHC at this point, as well.
| WeatherNut |
| (Weather Master) |
| Tue Aug 24 2010 01:56 AM |
| Attachment |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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It also looks to me like a westward movement. If it does miss this weakness, will it continue westward. with it being a stronger system will it be steered more by the 200-300mb layer flow? Looking at the latest graphics from CIMSS, thats what it looks like
| typhoon_tip |
| (Meteorologist) |
| Tue Aug 24 2010 02:03 AM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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Quote:
It also looks to me like a westward movement. If it does miss this weakness, will it continue westward. with it being a stronger system will it be steered more by the 200-300mb layer flow? Looking at the latest graphics from CIMSS, thats what it looks like
Track guidance beyond 72 hours is very difficult. There's just no way to know... For many runs, the numerical guidance had this weakness missing, now for a the last 18 hours (or 3 cycles worth) they have unanimously trended toward it turning smartly N and moving unimpeded right up the 50th parallel or so. The 18z runs of a few of these show an interesting bend back W around 84 hours or so, which "could" be an early indicator for troubling times ahead in the modeling.
As I was mentioning to Ed, if it misses the weakness it seems the most likely result would be a stall, or at least a very significant slowing with the potential for some meandering. The synoptic scale ridging along and off the East Coast could very well "trap" it between Bermuda and the outer Bahamas. But that is entirely supposition.
In the meantime, recent microwave passes shows a very discernible eye wall, and clear eye has developed, despite the fact that this does not show up very well in the other channels.
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Ed Dunham
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| (Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)) |
| Tue Aug 24 2010 02:06 AM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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You've made some good observations. I've taken a long look at the upper air and the ULL at about 27N is not particularly strong so it may end up not having as much of an immediate influence on Danielle's track as advertised. At 21Z NHC had the center at 15.4N and at 24/00Z they had it at 15.5N. Since 20Z I've pegged it between 15.2 and 15.3N - close enough since we are dealing with IR satellite - but the point of interest is about 6 hours of westerly movement in a pattern similar to yesterday evening. I said yesterday evening that the folks in the northern Leewards should monitor the progress of this system - and I still do since this is now the second episode of a bend to the left - and six hours is a rather lengthy 'wobble'.
The Islands are still probably okay given the strong tug to the northwest at least by 55-57W - but I wouldn't ignore the system until that northwest movement shows up (and stays that way).
And yes, I've looked at that steering from SSEC, but I think thats for the 700-850mb layer.
ED
| Ed in Va |
| (Weather Master) |
| Tue Aug 24 2010 02:54 AM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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The 11:00 is in...looks like the track has been nudged slightly to the left. Bermuda is now just outside the cone.
| WeatherNut |
| (Weather Master) |
| Tue Aug 24 2010 03:32 AM |
| Attachment |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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The eye just popped out on IR sat view
| berrywr |
| (Weather Analyst) |
| Tue Aug 24 2010 10:55 AM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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The ULL near 26N 57W last night will have no change is the storm's general track; however it will have a role in shear developing not from the northeast as it did a couple of days but from the southwest as models are now indicating and is likely to stifle any further intensification beginning in about 24 hours; possibly weakening the system. CIMMS shear analysis continues to depict an area of 20 knot from the southwest which Danielle will be traversing in a day or so.
| doug |
| (Weather Analyst) |
| Tue Aug 24 2010 01:50 PM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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It appears the WNW phase of Danielle's motion has begun and the NW'ly will begin at about 52W. The ULL does not seem to be too strong, but with the dry air it is hard to visually assess the degree of shear. It is not impacting the storm presently from all indications.
| Ed in Va |
| (Weather Master) |
| Tue Aug 24 2010 02:04 PM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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12Z models are out, with the main tracks moving several degrees left of the previous ones. Something to watch, especially for Bermuda
Hmmm...link doesn't work...go to Jonathan Vigh's model on the main page of Fl Hurr (under Danielle)
| Evan Johnson |
| (Weather Guru) |
| Tue Aug 24 2010 02:43 PM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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i concur, studying the last 7 hours of rainbows, it is dually noted that a jog to the west is current and a little bit of disorganization is also present. i still don't believe this is a game changer. keep something in mind, with how unpredictable the Atlantic has become, and with all the pressure systems involved, slight shifts in movement mean less than they used to in my personal opinion.
| typhoon_tip |
| (Meteorologist) |
| Tue Aug 24 2010 02:52 PM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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Quote:
i concur, studying the last 7 hours of rainbows, it is dually noted that a jog to the west is current and a little bit of disorganization is also present. i still don't believe this is a game changer. keep something in mind, with how unpredictable the Atlantic has become, and with all the pressure systems involved, slight shifts in movement mean less than they used to in my personal opinion.
The disorganization you are observing is real and it is quite evident that it is because Danielle is moving head-long into a region that was previously contiminated by Saharan Air Layering...
The reasons are complicated but SAL particulate matter is very bad for cloud seeding, and this thought to curtail cloud production ... therefore cutting into the dynamics of the system.
I mentioned this on another forum in length (can't recall if I did so here) that it would be possible that a would-be Danielle may get affected in this way. SAL, I believe (as I have been closely observing this season...) has been somewhat problematic in the middle Atlantic Basin, perhaps more so than predictively anticipated back in the spring.
It doesn't have to be a death sentence to Danielle, but the ideas of rapid intensity are put on hold indefinitely.
If the system shallows some, it may become more challenged to linking up with any weakness - something to consider as well.
Persons in the northern Islands should monitor this system.
| scottsvb |
| (Weather Master) |
| Tue Aug 24 2010 03:12 PM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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I really dont think the people in the Leeward islands have anything to worry about but swells that
were/are generated by the hurricane. I agree with every ones comments above and the SAL.
Drier air wrapped into the hurricane and shear is taking it toll on her.
I'm kinda inline with Doug on a WNW to NW path.. not so as much as the NHC has it..but
it wont move W towards 18N and 61W @ the Leewards. It may come close to 20N and 55W
and that is a key for Bermuda.
| MichaelA |
| (Weather Analyst) |
| Tue Aug 24 2010 04:16 PM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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Latest vis pic seems to show that the convection may be trying to reestablish near the CoC. Maybe the dry air entrainment is subsiding. With a weaker storm in the short term, a more westerly track may continue. I don't see a northwesterly turn until Danielle reaches somewhere near 20N; 60W.
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danielw
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| (Moderator) |
| Tue Aug 24 2010 04:24 PM |
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Hurricane Danielle
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RECON is flying the area west of Danielle. They are currently over the Eastern Caribbean at roughly 10,000 feet altitude.
Observation Time: Tuesday, 16:17Z
Radar Capability: Yes
Aircraft Altitude: Below 10,000 meters
Coordinates: 17.1N 65.0W (View map)
Location: 114 miles (184 km) to the SE (142°) from San Juan, Puerto Rico (USA).
Turbulence: None
Conditions Along Flight Route: In the clear
Pressure Altitude: 3,030 meters
Flight Level Wind: From 110° at 33 knots (From the ESE at ~ 37.9 mph)
- The above is a spot wind.
- Winds were obtained using doppler radar or inertial systems.
Flight Level Temperature: 9°C
Flight Level Dew Point: -9°C
Weather (within 30 nautical miles): Scattered clouds (trace to 4/8 cloud coverage)
700 mb Surface Altitude: 3,196 geopotential meters
Optional Data...
Estimated Surface Wind: From 70° at 15 knots (From the ENE at ~ 17.2 mph)
Remarks Section...
Surface Wind Speed (likely by SFMR): 18 knots (~ 20.7mph)
| doug |
| (Weather Analyst) |
| Tue Aug 24 2010 06:27 PM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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Yes I agree. It looks like it took a gulp of dry air earlier which collapsed the convection on the NW side, but that is beginning to reappear now. It is chugging along at a rapid clip.
| scottsvb |
| (Weather Master) |
| Tue Aug 24 2010 06:50 PM |
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Re: Hurricane Danielle
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Recon wont go out to Danielle..she is too far east. They almost never go east of 50W
| MichaelA |
| (Weather Analyst) |
| Tue Aug 24 2010 07:07 PM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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The latest Vis floater shows a CDO feature redeveloping over the center, so intensification should resume. Forward motion appears to be steady at about 300º.
| MichaelA |
| (Weather Analyst) |
| Tue Aug 24 2010 07:10 PM |
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Re: Hurricane Danielle
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But they will get some essential samples of the atmosphere ahead of Danielle that can be added to subsequent model runs. We'll see if that data changes upcoming runs.
| scottsvb |
| (Weather Master) |
| Tue Aug 24 2010 07:26 PM |
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Re: Hurricane Danielle
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They are just doing a test flight...
| WeatherNut |
| (Weather Master) |
| Tue Aug 24 2010 08:07 PM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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The 2pm models have shifted pretty substantially to the left with Bermuda about in the middle. It still seems like there will be a more westward track
| LoisCane |
| (Veteran Storm Chaser) |
| Tue Aug 24 2010 08:32 PM |
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Re: Hurricane Danielle
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love those samples of the atmosphere.... good idea
| MichaelA |
| (Weather Analyst) |
| Tue Aug 24 2010 09:45 PM |
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Re: Hurricane Danielle
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Latest Vis and IR RGB Sat Floater shows two major convective areas - one just NNE of the center, and one S of the center. There is still substantial dry air on the W side.
| scottsvb |
| (Weather Master) |
| Wed Aug 25 2010 12:15 AM |
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Re: Hurricane Danielle
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She has adjusted and is now moving more NW @ 320dg almost..
| berrywr |
| (Weather Analyst) |
| Wed Aug 25 2010 12:50 AM |
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Re: Hurricane Danielle
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Quote:
But they will get some essential samples of the atmosphere ahead of Danielle that can be added to subsequent model runs. We'll see if that data changes upcoming runs.
They really do need to sample the envelope Danielle is in as it is more and more appears likely Bermuda is under the gun and the Canadian GEM is hinting at a closer approach to the NE USA. All the model data in the universe can't replace real data and integrate them into the latest model runs.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Wed Aug 25 2010 01:16 AM |
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Re: Hurricane Danielle
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Mission synopsis: August 24, 2010
NOAA has no flights planned in the next 24 h. They will be watching developments in the Gulf of Mexico to determine if a flight on Thursday, August 26, is warranted. Currently they are planning to forward deploy to Barbados on Friday, August 27.
NASA completed a DC8 survey along the weak frontal zone on Tuesday, August 24. Take off time was 14 UTC and the flight duration was 8 h. The DC8 performed underflights of the TRMM PR and Aqua. No flights are planned through Friday. The Global Hawk conducted a low to mid altitude dropsonde test today. The first drop was successful. However, the second one failed. The test will be repeated on Thursday. A possible science flight into Tropical Storm Frank in the Eastern Pacific is planned for Saturday without dropsondes except for possible high-altitude test at the end if the flight on Thursday is successful.
PREDICT has no flight planned for Wednesday, August 25. A possible flight for August 26 is to be determined.
| LoisCane |
| (Veteran Storm Chaser) |
| Wed Aug 25 2010 02:10 AM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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So Ed in Va...am wondering what the local weather mets are saying tonight with the big shift in the models taking a weakened Danielle somewhere near your neck of the woods.
Well...am wondering if local mets up and down the coast are suddenly talking Danielle or are they all waiting to see what will be tomorrow.
Big shift in models... maybe just a funky run.
Time will tell
| Ed in Va |
| (Weather Master) |
| Wed Aug 25 2010 02:19 AM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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Lois,
Shift caught me napping...will check and let you know.
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MikeC
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| (Admin) |
| Wed Aug 25 2010 02:24 AM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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Odds are it's a bad run, but time will tell. I talked a bit about it in the forecast lounge.
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MikeC
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| (Admin) |
| Wed Aug 25 2010 02:40 AM |
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Re: Tropical Depression Six Upgraded to Tropical Storm Danielle
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Danielle is back to hurricane strength at 11PM, and the model spread at long range is increasing. It'll need another day or two of trends to be sure. Odds still keep it offshore the US.
| RevUp |
| (Weather Guru) |
| Wed Aug 25 2010 02:28 PM |
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Re: Hurricane Danielle
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Looks like a weak low-level circulation on VIS loop this morning about 250nm ESE of Brownsville, TX. Starting to show up on long range radar display. NOAA and NHC have it all covered quite well.
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Ed Dunham
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| (Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)) |
| Thu Aug 26 2010 01:54 PM |
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Re: Recurve is the Name of the Game
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As noted on the 09Z NHC Discussion for Tropical Storm Earl: "BASED ON THESE DATA...CONTINUITY WILL BE
MAINTAINED AND THE INITIAL POSITION IS NEAR THE NORTHERN
CLUSTER OF DEEP CONVECTION AND CLOSE TO THE TRMM FIX. IF THE
CIRCULATION CENTER DOES REFORM FARTHER SOUTH...THE FORECAST TRACK
WILL HAVE TO BE ADJUSTED SOUTH...OR TO THE LEFT OF THIS ADVISORY
PACKAGE."
At 26/12Z, NHC adjusted the center position south to 14.8N 35.4W which yields a west rather than a west northwest motion. I'd anticipate that the 15Z package will show a minor track adjustment to the left. Centerpoint positions are difficult to locate on formative systems at night but its likely that the adjusted 12Z position was used in the model run currently underway. Because some of the models use continuity as one of their parameters, its going to take an additional run or two for an adjusted track to emerge. With a persistent trough expected to maintain itself off the east coast, the overall recurve pattern still seems like the best solution at this time.
ED
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MikeC
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| (Admin) |
| Thu Aug 26 2010 03:15 PM |
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Re: Recurve is the Name of the Game
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The hurricane center mentioned a point about Earl (and Danielle) at the 11AM discussion, basically saying if Danielle recurves faster and or more abruptly than forecast, it could give a window for the ridge to reform near earl, keeping it a bit further west than the current track, which would possibly bring the Eastern Caribbean back in play.
Odds are against it, but if Earl's forecasted path were to change, that would be one of the reasons why, and something to watch for.
| LoisCane |
| (Veteran Storm Chaser) |
| Thu Aug 26 2010 03:58 PM |
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Re: Recurve is the Name of the Game
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Biggest question mark is where is the real center of Earl. The NHC said that not me...and it's a good discussion and a good question that begs answering. Without the exact center being right the models are almost useless.
Imagine when recon goes in and gets it exact we will know more and or... if his track shows us where he is at.
Easy to say recurve but it's a question on timing more than anything else...not just intensity of Danielle.
I'd like some answer before I believe he's swimming away from land.
| MichaelA |
| (Weather Analyst) |
| Thu Aug 26 2010 04:48 PM |
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Re: Recurve is the Name of the Game
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Looking at the latest floater vis loop, it looks like the center of Earl is moving between 270 and 280º along about 16ºN. That center is poorly defined though.
| Ed in Va |
| (Weather Master) |
| Thu Aug 26 2010 05:19 PM |
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Re: Recurve is the Name of the Game
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Huge track change to the left on 12Z GFS, with little sis Fiona to his SE. Only one run and the next could show him bypassing CONUS by 500 miles, but something to watch. We're a long ways from home on the fate on Earl.
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MikeC
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| (Admin) |
| Thu Aug 26 2010 05:29 PM |
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Re: Recurve is the Name of the Game
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97L is now being tracked, this is the wave east of Earl, and has a chance to form tomorrow or over the weekend. Odds favor this recurving as well, but has even less confidence than Earl.
(The map below may not be current, please check the dates~danielw)
{{StormLinks|97L|97|8|2010|3|97L}}
| scottsvb |
| (Weather Master) |
| Thu Aug 26 2010 05:30 PM |
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Re: Recurve is the Name of the Game
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Not even worth talking about until after 72-96hrs for the U.S. or recurving out to sea after that. Main thing
will be "Will this affect the NE Leeward islands". Tropical Systems are a near term thing (within 72hrs).
Also it will be important on the 60 longitude by day 4. GFS and ECMWF have it making it to 19-20N and 60W
by then. Lets first see if it goes north of 20-60 or middle or even 17-18N and affect the islands. Right
now its a good bet she will be somewhere between 18-20N and 60W by then.
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Ed Dunham
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| (Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)) |
| Thu Aug 26 2010 06:07 PM |
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Re: Recurve is the Name of the Game
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Earl has really taken a beating from the Saharan Air Layer - and it still is. At 26/16Z the NRL PREDICT Project Team had Earl at 15.3N 37.2W moving to the west and at 17Z the position was 15.3N 37.5W with a central pressure of 1010MB, i..e., at the moment, from their perspective, Earl is on life support. Until you have a halfway stable centerpoint, early upgrades can create track variability problems - and we are seeing some of that. In the past few hours the overall structure is showing signs of improvement.
ED
| doug |
| (Weather Analyst) |
| Thu Aug 26 2010 08:32 PM |
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Re: Recurve is the Name of the Game
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I see Earl at 15.3/38 now. it is very isolated, and surrounded in dry air. If the SAL prevents the convective processes from occurring there is virtually no other energy source for Earl to grab and strengthen. It has to manufacture its own or it will starve. Visible convection is away from the center. The circulation however is well established and that should allow better organization, which in turn will allow it to strengthen.
| WeatherNut |
| (Weather Master) |
| Thu Aug 26 2010 09:08 PM |
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Re: Recurve is the Name of the Game
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A data buoy near where Earl just reported a pressure of 1003mb
| berrywr |
| (Weather Analyst) |
| Thu Aug 26 2010 09:53 PM |
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Re: Recurve is the Name of the Game
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Earl is expected to be north and west of 20/60 in 120 hours. Initially models have recurvature tracing Danielle's track however not as abrupt. Earl is likely to make a much closer approach to the United States and may find itself stalled due to a number of features in play in one week. We all know model resolution at 168 hours is iffy at best. It will be 3 more days before we can really have a grasp how close Earl is going to approach; it will however be much, much closer this time around than Danielle. There is one fly in the ointment and that is 97L and maybe that impressive wave that's lighting up Africa as we speak.
Thanks to Ed and the link, I took a look at the SAL satellite imagery. A day ago the boys at NHC couldn't figure out why Danielle weakened to a tropical storm despite low shear values; it crossed through a tongue of the SAL.
The SAL has been slowly modifying while enveloped around Earl and his satellite presentation is improving and winds were raised slightly at 5pm.
Realistically, we're not going to know anything concrete for a few days and where all the major players will be.
| Clark |
| (Meteorologist) |
| Thu Aug 26 2010 10:14 PM |
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Re: Recurve is the Name of the Game
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Quote:
Earl has really taken a beating from the Saharan Air Layer - and it still is. At 26/16Z the NRL PREDICT Project Team had Earl at 15.3N 37.2W moving to the west and at 17Z the position was 15.3N 37.5W with a central pressure of 1010MB, i..e., at the moment, from their perspective, Earl is on life support. Until you have a halfway stable centerpoint, early upgrades can create track variability problems - and we are seeing some of that. In the past few hours the overall structure is showing signs of improvement.
ED
Just a quick heads-up, Ed: The intensities listed for each of the various "PGI" invest areas on the NRL PREDICT page are just placeholder values. They don't have any meaning whatsoever. The only information NRL gets from the PREDICT group for those invest areas is position. Since their system is set up to include an intensity designation, they just use 15 kt/1010 mb as a 'dummy' placeholder value. (Note the same that you see for Earl holds true for Danielle/31L, 97L/36L, and 37L in the Gulf.)
| LoisCane |
| (Veteran Storm Chaser) |
| Thu Aug 26 2010 11:09 PM |
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Re: Recurve is the Name of the Game
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Thanks Clark. A lot of variables on timing and exact location of where the center is and will be with Fiona and even Earl to start being sure where he will be or how far west he will be before he recurves... at the moment the west side of the cone is getting closer and closer to 70w.
Earl is a different storm from Danielle. I find it interesting that they are expecting Earl to be so strong at this point out on Day four... a possible category 4?? or strong 3... and everyone's talking about Fiona but she doesn't have the name yet.
This is one of the most amazing wave trains in a long time... and at some point the high won't predict the coast as things change, they are fluid.
As for how good 97 looks, it's early still... needs to cross the dry zone but she is lower
With multiple storms you have multiple variables and sometimes they interact...
Thanks for your help, Lois
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Ed Dunham
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| (Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)) |
| Thu Aug 26 2010 11:17 PM |
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Re: Recurve is the Name of the Game
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Thanks Clark, I knew about the 15 knots (which is why I didn't mention it), but not the pressure - meteorology is a constant process of learning.
As noted, the structure of Earl is getting a little better but the dry air has really put a crimp in the intensification process. I think that the key factor for the next few days centers on whether the ridge rebuilds behind Danielle before Earl can follow the weakness. I've been watching the variability between each official forecast of the latitude where Earl crosses 60W - varies from 20N to 22.5N so far. With a slow start in Earl's organization it could be close as to whether the center can get above 20N when it hits 60W if the current center location is correct.
ED
| StrmTrckrMiami |
| (Weather Guru) |
| Fri Aug 27 2010 01:14 AM |
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Re: Recurve is the Name of the Game
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Wow, it has gotten quite active in the end of August, which is to be expected since it is towards the end of the season and August and September are two of the most active hurricanes.
My question is, Invest 97L is the wave off of Africa, and the one in front is Earl right? I just want to make sure I am looking at this right, because plots for Invest 97L show it going up and just barely brushing Florida, then again, when I click on it, it doesn't show it being even close to that right now, so I guess I am a little confused.
| LoisCane |
| (Veteran Storm Chaser) |
| Fri Aug 27 2010 01:33 AM |
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Re: Recurve is the Name of the Game
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http://cimss.ssec.wisc.edu/tropic2/real-...0000&loop=0
Earl is looking a bit better tonight...
http://www.ssd.noaa.gov/goes/flt/t2/flash-ft.html
what amazes me is that this set up looks almost exactly like a few of the models looked about a week ago
http://cimss.ssec.wisc.edu/tropic2/predict/overshooting_tops/
3 storms step stairing their way across the Atlantic
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Ed Dunham
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| (Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)) |
| Fri Aug 27 2010 02:03 AM |
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Re: Recurve is the Name of the Game
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The answer to your question is 'yes'. Whatever you are looking at must be related to the previous version of Invest 97L back around the 20th of July that has not been updated yet.
ED
| StrmTrckrMiami |
| (Weather Guru) |
| Fri Aug 27 2010 02:19 AM |
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Re: Recurve is the Name of the Game
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Quote:
The answer to your question is 'yes'. Whatever you are looking at must be related to the previous version of Invest 97L back around the 20th of July that has not been updated yet.
ED
Thank you for Clarification. I am watching these three and am curious to see what they are doing, as it does look similar to the tracks three weeks back as someone else has already pointed out.
| WeatherNut |
| (Weather Master) |
| Fri Aug 27 2010 06:24 AM |
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Re: Recurve is the Name of the Game
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Looks like a special statement is out from NHC stating that Danielle is now a major hurricane w/ winds of 120mph. Est pressure is 955mb (funny how Alex bottomed out at 942 but was barely a cat2)
| Beach |
| (Weather Guru) |
| Fri Aug 27 2010 11:22 AM |
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Re: Recurve is the Name of the Game
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Looking this mornings loop:
http://www.ssd.noaa.gov/goes/flt/t1/flash-rb.html
I know storms wobble as they go along. Currently it looks like Danielle might pass 60W staying under 27N. I guess we'll know by 11:00am.
| LoisCane |
| (Veteran Storm Chaser) |
| Fri Aug 27 2010 11:39 AM |
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Re: Recurve is the Name of the Game
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it's a long wobble, barely north of due west
but would take more than a 3 hour wobble to say anything big is going on
storm is now a category 4 and that has a tendency to sometimes change things in the short term
thanks tho... was watching earl so much had not looked close up at Danielle
..................one thing that has always part bugged me and amazed me about her is she always seems upside down... seems to work for her but she always looks like she is looking out the rear view mirror, big long huge tail on the top side of her rather than the bottom side
| berrywr |
| (Weather Analyst) |
| Fri Aug 27 2010 03:02 PM |
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Re: Recurve is the Name of the Game
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The last couple of frames there has been a jog to the right and if this jog doesn't continue it will be west and left of track since the next positions are due north.
Earl is right on track however not as strong as Danielle which Earl at this point is tracing. Credit Ed with both and I agree...SAL and upwelling. That said, it's future track continues to be south of Danielle and the water is plenty warm along it.
The future of "Fiona" is interesting and the models don't have a good handle on this evolving system which as we know isn't a depression.
An impressive wave lies in the wings and it appears the parade is now in full motion.
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danielw
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| (Moderator) |
| Fri Aug 27 2010 05:58 PM |
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Re: Recurve is the Name of the Game
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Danielle ( no relation ) is just above the pressure wind relationship curve.
1000mb - 946mb = 54 + 75 mph = max possible windspeed with respect to pressure of 129 mph.
Not an impossibility as Katrina and Rita were both above the pressure wind relationship curve.
Danielle has a rather large storm envelope and satellite signature. As noted above, her main outflow channel is poleward which is slightly unusual. Poleward outflow channel is probably a better feeder right now as Earl's close proximity is preventing a equatorial outflow channel from staying intact.
Early Danielle also had a more pronounced poleward outflow channel while in close proximity to the ITCZ.
Strange, if not weird storm. Ed and Bill should be able to give a better reasoning of the poleward channel.
RECON is scheduled to fly Danielle this afternoon so we might be able to get a better grasp on what is making her tick.
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danielw
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| (Moderator) |
| Fri Aug 27 2010 06:19 PM |
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Danielle RECON Vortex Message
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Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 27th day of the month at 18:01Z
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 305)
Storm Number & Year: 06L in 2010
Storm Name: Danielle (flight in the North Atlantic basin)
Mission Number: 1
Observation Number: 11
A. Time of Center Fix: 27th day of the month at 17:35:30Z
B. Center Fix Coordinates: 26°59'N 60°05'W (26.9833N 60.0833W)
B. Center Fix Location: 464 miles (747 km) to the SE (142°) from Hamilton, Bermuda (GBR).
C. Minimum Height at Standard Level: 2,615m (8,579ft) at 700mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 101kts (~ 116.2mph)
E. Location of the Estimated Maximum Surface Wind: 9 nautical miles (10 statute miles) to the NW (325°) of center fix
F. Maximum Flight Level Wind Inbound: From 58° at 107kts (From the ENE at ~ 123.1mph)
G. Location of Maximum Flight Level Wind Inbound: 12 nautical miles (14 statute miles) to the NW (322°) of center fix
H. Minimum Sea Level Pressure: 942mb (27.82 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 10°C (50°F) at a pressure alt. of 3,055m (10,023ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 20°C (68°F) at a pressure alt. of 3,040m (9,974ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 13°C (55°F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Closed Wall
M. Eye Shape & Diameter: Circular with a diameter of 18 nautical miles (21 statute miles)
N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature
N. Fix Level: 700mb
O. Navigation Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 1 nautical mile
Remarks Section:
Maximum Flight Level Wind: 119kts (~ 136.9mph) in the northeast quadrant at 15:52:50Z
Maximum Flight Level Wind Outbound: 109kts (~ 125.4mph) in the southeast quadrant at 17:44:10Z
data courtesy of http://tropicalatlantic.com/recon/ ~danielw
Note:This vortex brings Danielle back into the norms with respect to pressure and wind relationship.
1000 - 942mb = 58 + 75 = 133 mph
We will have to see what NHC uses as the surface wind speed. Possibly 123 mph.