MikeC
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| (Admin) |
| Wed Jun 11 2008 12:17 PM |
Quiet Mid June
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It has been eleven days into the 2008 Atlantic Hurricane Season, and despite an early season storm in Arthur, it has been quiet, which is normal for this time of year.
It is rare to see a storm during the month of June. The climatology of this time of year, including the MJO (Madden-Julian oscillation) being negative for development now, makes conditions (atmosphere, water temperature, ect) generally poor for any type of tropical development.
If development were to occur in June, it's usually in the Southern Gulf of Mexico or in the Western Caribbean (where Arthur formed on May 31st). Last year also began with two early season storms as well, Subtropical Storm Andrea on May 9th, and Tropical Storm Barry on June 1st. There was no other tropical activity until July 30th.
As we look ahead to July, the area starts to widen mostly toward the eastern Caribbean and Atlantic east of the Caribbean. Usually storms do not get very large in July.
However, Dennis (formed July 4, 2005) and Emily (July 10, 2005) both became category 4 hurricanes in July and both were the strongest July Atlantic storms ever recorded in the Atlantic. (Dennis broke it first, followed by Emily topping Dennis.)
Dennis eventually made landfall as a weakening hurricane (Category 2 at landfall) just east of Pensacola on July 10, 2005. Emily moved into the Yucatan just south of Cozumel on July 18th, 2005 as a Category 4 storm.
Cape Verde Season (the time when storms form off of the coast of Africa) usually doesn't begin until Mid August, and this year looks like it won't be any different.
Right now nothing is going on in the tropics-- enjoy it because it may change later this season.
| MichaelA |
| (Weather Analyst) |
| Wed Jun 11 2008 01:34 PM |
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Re: Quiet Mid June
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Things have quieted down overnight with the wave approaching from the Atlantic and over in the SW Caribbean. Following the Atlantic wave is a large, moist surge and the deep moisture over FL continues to enhance the T-storm activity. Speaking of Cape Verde/Africa, the SSTs south of 15 degrees appear to be fairly warm, so an active Atlantic season might be possible this year. Of course, there are many more factors to consider.
| NewWatcher |
| (Storm Tracker) |
| Wed Jun 11 2008 02:52 PM |
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91L
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Actually the wave down by south america around 56W & 14N has been tagged as 91L. The shear has decreased and conditions seem more favorable for development. It also looks like it might just skirt the coast instead of heading straight into S.A.
P
| MichaelA |
| (Weather Analyst) |
| Wed Jun 11 2008 03:45 PM |
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Re: 91L
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Looking at the latest vis sat loop, it looks like the northern portion got sheared off and the southern portion is surviving for now. Seems headed for Trinidad/Tobago, but the Eastern Caribbean is usually a graveyard this time of year.
| HCW |
| (Storm Tracker) |
| Wed Jun 11 2008 03:52 PM |
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Re: 91L
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Looks like it will move into South America tonight before it has time to do anything. What about the system east of 91L would it have a better chance to form ? Here are a few early model runs on Invest 91L
http://my.sfwmd.gov/sfwmd/common/images/weather/plots/storm_91.gif
From TPC/NHC disco this morning...snipet...
TROPICAL WAVE IS ALONG 57W S OF 16N MOVING W NEAR 20 KT.
INVERTED-V LOW LEVEL SIGNATURE IS CLEARLY VISIBLE ON SATELLITE
IMAGERY. THE MIMIC-TPW ANIMATION SHOWS THE AXIS EMBEDDED WITHIN
A MOISTURE SURGE. AT THE CURRENT SPEED THE WAVE WILL BE NEAR THE
LESSER ANTILLES WED EVENING. ISOLATED MODERATE CONVECTION FROM
9N-13N BETWEEN 50W-57W.
| weathernet |
| (Storm Tracker) |
| Thu Jun 12 2008 04:44 AM |
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Re: 91L
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Interesting wave; however not sure whatever was tagged 91L, as what really catches my attention lies around 52W and 8N. Looks like a well defined low to mid level low with decent upper air, at this rather low lattitude. Granted, it has but little time to "do anything", given the proximity to S. America, however given a nice bit of bursting during the diurnal max and a little deepening, and it would not be such an oddity for the system to suddenly gain some lattitude if it were to develop. This all said, I find it particularly interesting that this tropical wave ( among others these past few weeks ) show the definition that it does, for this early in the season.
I have to say......, my opinion is contrary to those who consider the current conditions in the tropics to be "placid" or that quiet. The mid Atlantic high will vascillate of course, however seems to have become dominant with significant waves emerging off the African coast, some to maintain decent signature while traversing westward at a seemingly real low latitude, with the ridge conveniently angled so that some of these well defined waves may perhaps gain just enough latitude to possibly squeak into the E. Carib.
Maybe far little to garner any semplance of a pattern, however I am just starting to lean towards a belief that aside from the W. Carib., that in fact a "hot spot" for several systems to develop over the weeks/months to come, may be just East of the Windwards. Longer Cape Verde tracks may well ensue, come late August. If we maintain quite a strong Mid Atlantic ridge most of the season, than perhaps few if any systems may ever have the chance to bridge the Atlantic at the more typical latitiudes of 10-15 degrees. If all this were to come to pass, than "re-curving" tropical systems won't be the dominant theme of this season. That would not bode well for the Greater Antilles and the U.S. coastline in general. :?:
| nc_tropical_wx79 |
| (Weather Guru) |
| Thu Jun 12 2008 03:11 PM |
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Re: 91L (and Gulf Of Mexico)
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To me it looks like an area of disturbed weather has developed in the southern Gulf Of Mexico. What are the conditions (talking about shear, water temps, and direction steering winds are blowing in) in the southern gulf and does the are have a chance to develope?
| MichaelA |
| (Weather Analyst) |
| Thu Jun 12 2008 07:56 PM |
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Re: 91L
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Well, that went ashore in S. America. Looks like the shear in the Eastern Caribbean is still decreasing today and the wave at about 60 degrees longitude is looking a bit better this afternoon. Also, the weather is rather unsettled in the central GOM and the BOC today with the BOC looking a bit more vigorous.
| allan |
| (Weather Master) |
| Thu Jun 12 2008 08:27 PM |
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Re: 91L
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If you look at the disturbance in the GOM, it has a nice spin to it, convection, bit lopsided.. but that is normal for this time of year isn't it? An Invest tag would be possible, shear is decreasing a bit to the north according to the CIMMS shear map which is a great map to locate shear. As for what was 91L, that's on land, but the wave to the north and east of it, has what looks like a mid level spin, it is possible that it works its way down to the low levels, but then it's future is so little due to a nice swath of 30-40 knots of shear to the north. Otherwise, the tropics are a bit active then what it normally should be but this has been the "unusuall year".
| dem05 |
| (User) |
| Fri Jun 13 2008 12:15 AM |
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Re: Brewing in the SE
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Well, not much going on in the tropics right now...
The area in the Gulf of Mexico is a mid level area of vorticity, which is likely a remenant reflection of thunderstorms that moved off the Yucatan Penninsul yesterday afternoon plus the combination of some mid level reflection of the Upper Level Low that is in the Bay of Camp. There isn't any evidence that this will transition into a tropical cyclone as low level cloud motion is moving fairly swiftly as ese'rly and se'rly winds underneath the entire area. There is no support for a low level transition out there under these circumstances. Thunderstorm development remains unimpressive and actually shows continued evidence of winding down. So it doesn't look like the Gulf of Mexico will be an area of development with this feature.
The disturbed area east of the windwards may be something to watch once it reaches the western Caribbean in several days. For now, the area remains unconducive for development and the thunderstorms...as active and "blobular" as they may seem, are well removed to the NE from the most ideal area of turning. The continued shear may keep those storms going, but will proclude development. In the next day or so, the wave will encounter increasingly inhospitable conditions in the Eastern Caribbean Hurricane Boneyard. Especially considering the southerly track this wave will be moving along (i.e. mostly over land)...So in 3 days...we shall see what may be left of it and what the conditions of the western Caribbean may be.
| Beach |
| (Weather Guru) |
| Fri Jun 13 2008 12:47 AM |
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Re: Brewing in the SE
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I think where the disturbance is in regards to the HIGH pressure off of the East Coast, if it did gather itself some
the water is warm enough.
http://www.ssd.noaa.gov/goes/east/carb/loop-wv.html
Like you said, lets see what happens in a day or two.
| JoshuaK |
| (Weather Guru) |
| Fri Jun 13 2008 02:44 AM |
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Re: Brewing in the SE
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Tropical Wave in the Winward Islands looks extremley impressive right now, I think this system is rapidly becoming TD#2. I do detect spin, as circled below in the little satellite photo snippets. But very impressive looking system right now.
| dem05 |
| (User) |
| Fri Jun 13 2008 02:52 AM |
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Re: Brewing in the SE
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The water temp is at levels that "could" support development in the far western Atlantic under the approriate conditions. However, the upper level winds are quite prohibitive. At this time, there is a large fetch of westerly and west-south westerly (Upper Level) winds moving across northern South America, the Caribbean, and in particular, the northern Caribbean, Greater Antillies and the west Atlantic (east of the Leewards). The true remenant of 91L is currently moving through Venezuala. The thunderstorm activity presently moving NW toward the Leewards is from the wave that was behind it. It will be interesting to see if the wave from behind continues to move NW or if they keep releatively close together during a continued progression that has been generally toward the WNW. If circumstances (Upper level winds) in the western Caribbean were to improve, then there would be a shot a development. Especially if we get more than one wave to pile up under favorable conditions. Otherwise...development looks like a no go...The models depict this and the satellite imagery (Water Vapor) continue to show unfavorable conditions for development.
| doug |
| (Weather Analyst) |
| Fri Jun 13 2008 12:01 PM |
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Re: Quiet Mid June
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The convection which had been accompaning 91L, the wave crossing the islands in the E. Carribean has diminished in the last 12 hours. This seems in part to the shear over the system. The showers are well north of the low latitudes where the cyclonic spin exists, if there was one. With the SW'ly shear there is no hope for any regeneration or growth in this system.
ALL is quiet.
| tropics |
| (Registered User) |
| Fri Jun 13 2008 03:06 PM |
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Re: Quiet Mid June
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Hey guys, I've been lurking here for a couple years now (I've mostly posted on hardcoreweather and storm2ks boards) but have decided to make an account and provide some of my analysis.
While the wave approaching the eastern Caribbean looked decent going in to the over night hours with the aid of diurnal maximum, convection has really tapered off early this morning. Looking at WV images the majority of the Atlantic is covered with subsidence subduing most convection. Also this wave is beginning to enter a high shear environment. Models do suggest that the strong upper-level winds will being to weaken in the early parts of next week over the western Caribbean but we'll have to wait and see what condition this wave will be left in by then.
Convection can once again be seen forming to the north of the Yucatan Peninsula across most of the GOM as a result of the tropical wave along 95W and 22N and a weak ULL to the northeast.
(For future reference, the material below belongs in the Everything & Nothing Forum. Talkback posts/responses on the Main Page Talkback should be confined to the Atlantic Basin only - and to the topics that have been covered in the leadoff article for this thread. See the current Met Blog and the Site Rules for posting guidelines.)
Some of this moisture will likely be pulled north by the high pressure system centered over the southeastern U.S. and intermingle with the stalled out cold front that is being aided by the Omega Block (two low pressure systems, one located to the northeast and one to the northwest, with the high pressure system located to the south) bringing more rain to the midwestern U.S. and an area already devastated by torrential flooding and tornadoes.
Nothing of real interest in the immediate future regarding the tropics.
(Off-topic material deleted - see the Forecast Lounge.)
| JoshuaK |
| (Weather Guru) |
| Fri Jun 13 2008 06:20 PM |
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Re: Quiet Mid June
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I saw that. I'm so dissapointed too, it was looking good for awhile and I was excited at the prospect of a TD forming in the East Caribbean at this time of year.
But GOES Atlantic Floater 3 currently has an Invest under way concerning the area of disturbed weather in the BoC, and this area is looking more impressive this afternoon. How are wind shear and other conditions in the BoC right now?
| tropics |
| (Registered User) |
| Fri Jun 13 2008 08:05 PM |
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Re: Quiet Mid June
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It's under about 20 knots of shear currently. So far no apparent surface circulation can be observed on visible satellite imagery. If anything were to form it would be from the upper-level low at 22N93W working its way down to the surface. Convection has begun to fire up over this ULL but considering the shear values it would have a tough time really getting itself together.
| Unregistered User |
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| Sun Jun 15 2008 01:22 PM |
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Re: Quiet Mid June
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Well, checking the Eastern Atlantic floater this morning(METEOSAT-8 updated every 6 hours), I must say that I was very impressed with a new tropical wave which was around 27W and south of 10 N. There is some dry air aloft in that region but I think it should be noted that such an impressive wave coming off the coast of Africa at this time of the year. Right now its fairly disorganized but it should be watched.
| DarleneCane |
| (Verified CFHC User) |
| Sun Jun 15 2008 08:56 PM |
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Re: Quiet Mid June
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It's hard not to watch it but climo is very against it forming into anything. It is noteworthy though that it still has maintained it's shape and not fizzled as so many other waves this time of year in other years do.
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MikeC
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| (Admin) |
| Mon Jun 16 2008 07:53 PM |
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Re: Quiet Mid June
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Conditions are very unfavorable for Cape Verde/African storms, everythng there until late July or mid August even likely will fall apart rather quickly.
Take a look At this link to see all the June Storm tracks (Tropical Storm or greater) to check this out.
Then check out July (Hurricanes Only) Here
And to top it off, here are all the June and July storms that formed East of 50W since 1900. (Actually just July since no recorded storm formed east of 50W in June)
| Unregistered User |
| (Unregistered) |
| Wed Jun 18 2008 12:59 PM |
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Re: Quiet Mid June
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You may be right Mike, but you must admit, the quality of tropical waves coming off the African coast at this time of year is quite high(considering years before). If this continues throughout the season, then we may be in for a rough ride:(:(. I think people are underestimating this wave in the Mid-Atlantic. Who knows, maybe you guys are right and its just a minor wave that won't develop due to harsh conditions(upper level winds etc.). I for one, will be keeping a very close watch on this one until it dissipates as forecasted(after all, I am from Barbados and its forecast to reach me by tomorrow evening).
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MikeC
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| (Admin) |
| Wed Jun 18 2008 05:54 PM |
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Re: Quiet Mid June
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The one out there (800 miles east of the Winwards) may be worthy of the NRL's "Invest" status, but it's about to hit a huge wall of horrible conditions for development, it likely won't last to tomorrow. So interesting flare up, but should be short lived.