MikeCAdministrator
(Admin)
Mon Jul 21 2008 11:49 AM
Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Corpus Christi

5:00 PM CDT 22 July Update

Dolly's internal structure has improved this afternoon. Recent IR and hi resolution visible imagery strongly argue for the production of an eye. We are also see the explosive genesis of a CDO feature. This combined with recent reconnaissance report of 75kt flight level wind has prompted NHC to upgrade Dolly to hurricane status.

As of the 5pm update, her forward motion has been decreasing slightly and is now northwest at 10mph. Central pressure was ~ 986mb and her maximum winds were set at 75mph.

Oceanic heat content remains good, shear has relaxed considerable over what Dolly experienced with the TUTT yesterday, and upper level divergence is looking good with clear anticyclonic outflow established. There is just every so slightly some impinging southerly winds do to the TUTTs final last tentacles of contact, but it appears these are too weak at this point to be much of any significant mitigation to development. It is for these reasons that the official intensity by NHC is set a little higher than the more robust model solutions, now taking Dolly to 80kts just prior to making landfall. It should be noted however, that a couple of higher resolution models (discussed below) are a tad slower and farther north along the coast. The longer Dolly stays over the warm waters of the Gulf, the stronger she may become.

There is some contention during the afternoon on where/when Dolly will cross the coastline. Earlier runs had somewhat tightly clustered around an ~ Brownsville landing. However, a couple of the higher resolution models, including the WRF and the HWRF, are bringing Dolly up farther along the TX Coast before turning her left and on land. For this reason, folks up into the Bend area of the TX Coast need to monitor this with due diligence. This is also a good time to remind people not focus on the exact location the actual eye crosses the coast, and to pay close attention to the wind field radii information.

This is also going to be a slow mover as it comes in land. Citizens in the interior parts of southern TX and near the Rio Grande valley need to take early precautionary measure to protect against the threat of flooding for what is likely to be a protracted period of excessive rainfall while Dolly slowly winds down.

John (typhoon_tip)

11:00 AM EDT/10:00 AM CDT 22 July Update
Dolly remains a Tropical Storm for now the TUTT/Upper low is still holding it in and it will do so unless it escapes it entirely it will remain a Category 2 system or lower.

Hurricane Warnings were lowered to Tropical Storm Warnings north of Corpus Christi.

It will likely slowly strengthen today.

Links for Webcams, Radar, and news outlets in the area have been posted toward the bottom of this article, including 4 flhurricane recordings.


8:00 AM EDT/7:00 AM CDT 22 July Update
Dolly is finally starting to shake (but hasn't completely) the effect of the Tutt Upper Level Low (now over the western edge of the Bay of Campeche) and is starting to slow down as mentioned by prior National Hurricane Center forecasts. Indications are it will likely slowly gain strength throughout the day. Pressure is now 993 mb and windspeed is at 65MPH.

Dolly should become a hurricane later this morning and likely gain strength throughout the day. Since the outflow problems that it was having seem to be going away, it could undergo rapid intensification (This is very unpredictable... most likely it will not and stay Category 2 or lower) Folks in Northern Mexico and southern Texas (The Hurricane Warnings) should rush any more preparations today as conditions will start to deteriorate this evening.

10:55PM EDT/9:55PM CDT Update
The earlier hurricane watch area has now been upgraded to a Hurricane Warning. A tropical storm warning is up from Port O'Conor to San Luis pass, Also the Hurricane Warning enters Mexico to San Fernando.

The National hurricane center expects Dolly to become a hurricane but not a Major Hurricane. Likely a Category 1 at landfall, right at or just south of the Texas/Mexico border Wednesday morning (around 7 or 8 am CDT). Locations just to the north of the landfall point will likely see most of the worst weather.

6:55PM EDT/5:55PM CDT Update
New minimum lowest pressure from recon confirms strengthening, down to 998mb from 1004.


Take a guess at where Dolly will go and how strong, Let us know in the Forecast Lounge... (Click here to add your comment) orhere to see others

6:46PM EDT/5:46PM CDT Update
There are some signs now that Dolly has begun strengthening, a new Recon plane is on it's way and finding lower pressure already (before reaching the system), and it appears from the visible and IR satellite that a Central Dense Overcast (CDO) is forming near the Center of Dolly.



The mid level dry socket wrapping in from the east and south is starting to become filled in, setting the stage for possible strengthening this evening. If the new Central Convection holds it will likely build quickly.

5:00PM EDT/4:00PM CDT Update
There is not too much new to report, recon has still been struggling to find a true center, but has indeed found one. The movement is still west northwest at around 18MPH. Dolly is expected to start slowing down forward motion tomorrow morning.

The watches are still up and portions of them may enter into warnings later tonight or tomorrow morning.

Satellite presentation of Dolly is very mixed, currently the western edge seems to be fairly well defined, but the southeastern section has a very interesting dry section that follows along to a remnant of the TUTT in the Bay of Campeche. This is the only really negative thing going for it. The water temperatures, shear and anticyclone above it are all favorable for development. But with a lack of a really solid inner core, not too much can happen. If it does form, it could increase rapidly.

There is the potential for a rapid ramp up before landfall, which is why everyone in the watch area must start some preparations, and when hurricane warnings go into effect, execute them. Although the chances of a rapid intensity increase are only about 20%, it's still possible. Areas at and north of the eventual landfall point will likely see the worst of whatever Dolly brings. There is no good reason doubt the forecast track that the National Hurricane Center has put out.

Those in the watch/warning area need to listen to officials and local media, and as warnings approach, get off the Internet and do some preparations. Do the prudent thing here, although it is most likely that Dolly will not gain too much strength, the chance is high enough where you need to prepare for it or worse. Rule of thumb is to prepare for 1 category level above what is forecast.

2:00PM EDT/1:00PM CDT Update
Dolly is maintaining its windspeed direction and movement as of the 2PM EDT advisory according to recon.

The models have shifted a bit south, but still don't have the best handle on the system.

It appears the National Hurricane Center's forecast track will be good.

Hurricane Watches Up in Texas Brownsville to Port O'Connor, Tropical Storm watch from Port O'Connor to San Luis Pass.

Mexico has a hurricane watch from Rio San Fernando to the US/Mexico Border.



10:56AM EDT/9:56AM CDT Update
Hurricane Watches Up in Texas Brownsville to Port O'Connor, Tropical Storm watch from Port O'Connor to San Luis Pass.

Mexico has a hurricane watch from Rio San Fernando to the US/Mexico Border.

Looks like since the early AM, the surface low has indeed formed, the Hurricane Center is suggesting intensification, so those in the hurricane watch areas need to be beginning hurricane preparations. Do not focus on the landfall point, those (especially to the north) are forecast to possibly see hurricane condition within 36-48 hours.

There is a chance that the storm may slow its forward motion as it nears the coast.

More to come soon.

10:38AM EDT/9:38AM CDT Update
Recon just sent back a vortex message,

Center:
22° 04' N 89° 10' W (22.1°N 89.2°W)

Surface winds roughly 55MPH. This implies it is forming further north.
10AM EDT/9CDT Update
Recon yet again did not find a distinct low level circulation center, this probably means it is up for formation, best guestimate right now (which may change in a few minutes) may be a little to the east of where the main blob is now.

Also most of the convection is on the northern side of the system, so those to the north (right) of the landfall point will likely see the worst of whatever Dolly Brings.

Shear is nonexistant right now, water temperatures are warm, movement is fairly fast west northwest right now, however some slowdown and collapse of steering currents may happen late tomorrow.

Everyone in the cone of probability needs to be watching Dolly closely.

Original Update
Tropical Storm Cristobal is now moving away from the Carolinas and out to sea as a 50 MPH Tropical Storm. It brought some rainfall to the Carolina coast, but most of the heavy convection was over the ocean. Cristobal never made landfall on the US.

Tropical Storm Dolly is highly questionable this morning. This system has been very resistant to tropical development for a week now, and even as a named system it seems to be missing a low level circulation. And without a Low-Level Circulation the argument that it is not a Tropical Cyclone could be made. Convection wise, cloud tops are very cold, and the convection that is there is pretty strong.

Dolly's center position was readjusted to the north overnight and it is now re-emerging into the Gulf of Mexico, and now is moving generally west-northwest, which suggests the National Hurricane Center's track is still pretty good.

From analyzing it this morning, it seems the forecast track may have to be adjusted to the left (south, more into Mexico) if the current trend continues. The ridge to the north and the fact that it remains very weak and not so organized is suggesting that it will likely keep the more westerly track.



Northern Mexico probably has the best chance of seeing a landfall. Since the center may be more at the Mid-Levels (again a questionable tropical cyclone) it's very possible the system could reform its center again. Aircraft Recon is out checking out dolly now to help determine this.

What do you think Dolly will do? Let us know in the Forecast Lounge (Click here)

The lack of a good circulation center will keep the entire cone watching, from South Texas to Mexico (more likely Northern Mexico). Intensity wise, it's even harder to say. Following persistent trends suggest it may stay weak, but the Gulf of Mexico is known to change things.

Outside of this, an unusually vigorous wave is exiting the African coastline, and if it persists we'll have something else to track for a good while. More discussion on this wave can be found here



More to come later

Event Related Links

Cozumel Weather
Cancun Radar Cancun Radar Loop (Flhurricane long term recording)

{{radarlink|bro|Brownsville, TX Radar}}
{{radarlink|crp|Corpus Christi, TX Radar}}
Texas/South Plains Radar Composite

Southeast Radar Composite (loop)

Local Media:

Brownsville Herald
The Monitor
Valley Morning Star
KGBT 4 News
KRGV Newschannel 5
KURV 710 News/Talk

Webcams:
Coastal Surfing Pier Cam (Corpus Christi)
South Padre Island Cams: BeachCam SurfCam Bay Cam
Rio Grande Cam in Mission, TX
Matamoros/Brownsvillle Cams

Recordings:
Dolly Brownsville Level 3 Radar (Now Active)
South Padre Beach Cam
South Padre Island Surf Cam -- High Res (Not Active Yet)
South Padre Island Bay Cam (Now Active)



{{StormLinks|Dolly|04|4|2008|2|Dolly}}
{{StormLinks|Cristobal|03|3|2008|4|Cristobal}}
{{StormLinks|97L|97|5|2008|1|97L}}


MikeCAdministrator
(Admin)
Mon Jul 21 2008 01:28 PM
Re: Cristobal Out to Sea, Dolly in Gulf, Questions

Since I got a few emails about this this morning.... Things may change pretty quickly with Dolly, so just wanted to put up a reminder to keep watch, especially through the afternoon. Although the westerly track is more likely, if Dolly does get organized and gains strength then northerly is definitely possible as well.

Dvorak T Numbers are around 3.0, so it is doing pretty well convection wise right now. If recon finds evidence of a Low Level Circulation then those numbers will be important.

Everyone in that forecast cone needs to be watching this system.


craigm
(Storm Tracker)
Mon Jul 21 2008 02:04 PM
Re: Cristobal Out to Sea, Dolly in Gulf, Questions

Dolly is really moving. At this speed warnings will be up along the Texas/ Mexican coast within 24 hours unless she slows down. Notice I didn't say what flavor of warning.

MikeCAdministrator
(Admin)
Mon Jul 21 2008 02:40 PM
Re: Cristobal Out to Sea, Dolly in Gulf, Questions

Recon just sent back a vortex message,

Center:
22° 04' N 89° 10' W (22.1°N 89.2°W)

Surface winds roughly 55MPH. This implies it is forming further north.


cieldumort
(Moderator)
Mon Jul 21 2008 02:58 PM
Re: Cristobal Out to Sea, Dolly in Gulf, Questions

A rough extrapolation of this fix suggests that indeed Dolly has hooked to a WNW course, once leaving the tip of the Yucatan, and having previously been on a NW course (smoothed out and accounting for center jumps). Extending this motion all the way out to landfall, extreme south Texas/ extreme NE Mexico does still appear to be the target... but only if one draws a pretty strait line, and Dolly then follows marching orders to the letter.

A strengthening Dolly might now be in order, but her continued on again off again connection to the surface, and rather oblong, loopy convective appearance on satellite, suggests s l o w strengthening, if any, in the near term. Even with some gradual improvement today, I do not perceive any reason to suspect much in the way of any possible deviation from the currently expected WNW track, baring any more center reformations, for the remainder of today.


typhoon_tip
(Meteorologist)
Mon Jul 21 2008 05:01 PM
Re: Cristobal Out to Sea, Dolly in Gulf, Questions

Quote:

Since I got a few emails about this this morning.... Things may change pretty quickly with Dolly, so just wanted to put up a reminder to keep watch, especially through the afternoon. Although the westerly track is more likely, if Dolly does get organized and gains strength then northerly is definitely possible as well.

Dvorak T Numbers are around 3.0, so it is doing pretty well convection wise right now. If recon finds evidence of a Low Level Circulation then those numbers will be important.

Everyone in that forecast cone needs to be watching this system.




Right now Dolly is being guided swiftly along by a ridge axis over the SE U.S. However, most global numerical models predict the influence of this large scale synoptic feature to wane enough to weaken the steering field substantially. This should induce a slowing of the forward speed beginning at ~ 60 hours.

It should be noted that in addition to slowing...a few of the overnight track guidance have shifted substantially north of the previous runs. The 06z GFDL and HWRF, for example, take Dolly to over 90kts and bring her ashore in the TX Bend area...perhaps missing Mexico altogether in these solutions. While such details are far from certain, you do bring up a good point that might be a harbinger, relating to a stronger system having more polar-ward ascent. Overnight...as we noted by a number of posters and apparently confirmed, Dolly did a center jump, such that much of her circulation managed to stay over water...not encountering the deleterious effects of land. This asserts a stronger ramp up curve (potentially), but more importantly, most of the past guidance was based on a weaker system that passed more bodily over the Peninsula. Since that did not take place, the 12z runs will be more telling.

There is a con and a pro at the moment, to faster intensification:
A broad circumavallate requires a longer duration to concentrate a core;
In about 1 day, Dolly will be moving headlong across a very rich oceanic heat content, where the thermocline extends quite deep...indicating more than the usual heat content (we saw what Katrina did when she passed over such feature in the eastern Gulf).

..Because the overall environment has recently gone from marginal/shear, to very little shear with an upper level anticyclone sprawling all the western Gulf, I'm going to go ahead assume the upper ends of the intensity spectrum will be achieved. Part of this decision is also based on tropical cyclones, once garnered enough momentum, tend to exceed guidance better than 50% of the time. Since (finally) a real central axis to the circulation is definable (hi res visible imagery), she's developing an inner core and it appear that threshold is nearing. I like the NHC's idea to go a bit aggressive, while perhaps conserving a little do to Dolly's large size.


danielwAdministrator
(Moderator)
Mon Jul 21 2008 06:16 PM
Re: Cristobal Out to Sea, Dolly in Gulf, Questions

I bit of a different view. Different color filters used here:



image courtesy of NOAA~danielw


typhoon_tip
(Meteorologist)
Mon Jul 21 2008 06:24 PM
Re: Cristobal Out to Sea, Dolly in Gulf, Questions

Nice image...

The IR channel at TPC is indicating a rather shredded looking Dolly this mid-day, though. Despite some of the discussion points being made by all...I am bemused to note there is still a TUTT presence near the lower BOC area, and this I think I'll have to admit is effecting Dolly still more than we and NHC previously believed.

If you go here, http://www.ssd.noaa.gov/goes/flt/t2/loop-avn.html, and then click the wind overlays you can really detect that taking place. Hard to say what's in store for the next 24 hours, but this feature is supposed to be fully pulling away.


MikeCAdministrator
(Admin)
Mon Jul 21 2008 06:35 PM
Re: Cristobal Out to Sea, Dolly in Gulf, Questions

Quote:

Nice image...

The IR channel at TPC is indicating a rather shredded looking Dolly this mid-day, though. Despite some of the discussion points being made by all...I am bemused to note there is still a TUTT presence near the lower BOC area, and this I think I'll have to admit is effecting Dolly still more than we and NHC previously believed.

If you go here, http://www.ssd.noaa.gov/goes/flt/t2/loop-avn.html, and then click the wind overlays you can really detect that taking place. Hard to say what's in store for the next 24 hours, but this feature is supposed to be fully pulling away.




I've been looking like crazy for the reason for Dolly not really getting itself together and that's about the best reason I've seen yet. Thanks for pointing that out. It has probably pushed the center reformations yet. I hope this sticks around as it will keep Dolly weaker.


Storm Hunter
(Veteran Storm Chaser)
Mon Jul 21 2008 07:28 PM
Re: Cristobal Out to Sea, Dolly in Gulf, Questions

AFRecon just went back threw Dolly.. pressure falling .. dwn 1mb to 1004mb

Observation Number: 08
A. Time of Center Fix: 21st day of the month at 19:01:00Z
B. Center Fix Coordinates: 22°46'N 90°43'W (22.77N 90.72W)
B. Center Fix Location: 143 miles (230 km) to the NNW (330°) from Mérida, Yucatán, México.
C. Minimum Height at Standard Level: Not Available
D. Estimated (by SFMR or visually) Maximum Surface Wind: 32kts (~ 36.8mph)
E. Location of the Estimated Maximum Surface Wind: 32 nautical miles (37 statute miles) to the ESE (107°) of center fix
F. Maximum Flight Level Wind Inbound: From 179° at 31kts (From the S at ~ 35.7mph)
G. Location of Maximum Flight Level Wind Inbound: 33 nautical miles (38 statute miles) to the ESE (108°) of center fix
H. Minimum Sea Level Pressure: 1004mb (29.65 inHg) - Extrapolated
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 22°C (72°F) at a pressure alt. of 365m (1,198ft)


danielwAdministrator
(Moderator)
Mon Jul 21 2008 08:24 PM
DOL and LY

Checking back in I see that you've been dicussing what I thought I was seeing on the TWC Dreamcicle loops.

Dolly appear to have a split personality. And an appearance somewhat like a crescent roll.



LLCC is to the western side of the CoC. But keep an eye on the NE Quadrant. That, at first glance, appears to have a mid level circulation.

By the way. The extreme outer circulation around Dolly is affecting the weather here, 65 miles inland. Winds from the East at 5 to 10 mph and all of the afternoon thundershowers are moving toward the West.


danielwAdministrator
(Moderator)
Mon Jul 21 2008 08:33 PM
Recon

Recon is consistantly flying the 1000mb level or around 1000 ft abaove the surface. This is Normal for an INVEST but slightly abnormal for a Tropical Storm. They should be flying the 850mb or 700mb levels. 5000 and 10000 feet, respectively.

Obvious they are looking for an anomaly of some type... Dolly seems to fit the word, Anomaly, as a whole.

Water vapor sat photo supports the TUTT theory discussed above.


Storm Hunter
(Veteran Storm Chaser)
Mon Jul 21 2008 10:15 PM
Attachment
Re: Recon

well... AF Recon is back home now, but NOAA Reg. Num. N43RF, Nickname "Miss Piggy" is about to arrive very shortly. Descending down through 8,000ft coming in from the NE side of Dolly.. I would suspect that they would heavy fly the SE side of the center... to get some lower to mid upper air data... which i think is a factor in why Dolly hasn't taken off with convection, YET...


**side note.. about 10 mins ago.. NOAA9 and NOAA3 passed each other by about 50-60miles... pretty sure the jet could of seen the P-3** looks like NOAA9 is almost done with its mission...


Storm Hunter
(Veteran Storm Chaser)
Mon Jul 21 2008 10:49 PM
Attachment
Re: Recon

latest data from NOAA3... there almost to the center... and i would think that sense there staying at about 7,550ft.. on the inbound.. there mission is a little different, or they may see a closed center on radar on the plane... last check there about 20 miles from center of Dolly.. winds at flight level at 7,749ft... From 117° at 40 knots (From the ESE at ~ 46.0 mph... they should be hitting the convection soon.

see attached


MikeCAdministrator
(Admin)
Mon Jul 21 2008 11:02 PM
Re: Recon

Safe to say now that Dolly is over the hump and is now in strengthening mode, unfortunately for those in the Path. Again, if you are please make preparations now, as it could potentially strengthen quite a bit before landfall. 986 mb from some of the recon recently is one indication. I still would like to see a full Vortex message, however.

Storm Hunter
(Veteran Storm Chaser)
Mon Jul 21 2008 11:09 PM
Attachment
Re: Recon

Vortex from center should be in shortly.. next few mins... dropsonde from about 60miles out came in about 10 mins ago... NOAA3 is well to the SW of center now... they flew through from NE to SW.

Flight LEVEL center was at:

Time:
22:38:00Z
Coordinates:
22.97N 91.63W
Acft. Static Air Press:
759.0 mb (~ 22.41 inHg)
Acft. Geopotential Hgt:
2,391 meters (~ 7,844 feet)
Extrap. Sfc. Press:
998.6 mb (~ 29.49 inHg)
D-value:
-
Flt. Lvl. Wind (30s):
From 39° at 7 knots (From the NE at ~ 8.0 mph)
Air Temp:
14.5°C (~ 58.1°F)
Dew Pt:
14.5°C (~ 58.1°F)
Peak (10s) Flt. Lvl. Wind:
9 knots (~ 10.3 mph)
SFMR Peak (10s) Sfc. Wind:
23 knots (~ 26.4 mph)
SFMR Rain Rate:
7 mm/hr (~ 0.28 in/hr)

**see close up attachment image

UPDATE: Just got a dropsonde.. but it was to the southwest of the CoC...


WeatherNut
(Weather Master)
Tue Jul 22 2008 02:13 AM
Re: Recon

The last couple of frames are now showing an eye in the middle of the CDO. Is there a recon in there now?

LoisCane
(Veteran Storm Chaser)
Tue Jul 22 2008 02:29 AM
Re: Recon

not sure but there are enough eyes in the sky on her

she seems to have an affinity for intensifying just prior to the 11pm and then we have to wait up with her to see what she is doing

she is slowing it seems and if she does... she will intensify, as much as she is an anomaly she works on basic science.. sitting over warm water should spark up her convection around the center seriously over the next few hours or later tonight


keep watching


WeatherNut
(Weather Master)
Tue Jul 22 2008 02:34 AM
Re: Recon

They got a pressure reading of 985 23.20N 92.40W.
I dont think they are near the center yet either


cieldumort
(Moderator)
Tue Jul 22 2008 02:37 AM
Re: Hurricane Watches Up in Texas Brownsville to Port O'Connor

This is a little bit of an eye-opener. Might be one bad read, but then again, with an apparent eye formation now underway, maybe not. It may just take the winds a few more hours to really catch up.

Time, Location and Flight Level:
02:22:00Z 23.20N 92.40W 766.5 mb, 2,305 meters (flight level pressure, flight level)

Pressure:
Extrap: 985.0 mb (~ 29.09 inHg)

Peak 10-second Flight-level winds:
78 knots (~ 89.7 mph)


danielwAdministrator
(Moderator)
Tue Jul 22 2008 03:21 AM
HDOB Wind Speeds

The "78 knots(~ 89.7 mph)" is highly suspect to me. The wind speeds prior to and after that particular reading are more consistant with the rest of the flight leg.

The "985.0 mb(~ 29.09 inHg)" pressure reading looks consistant with the other flight level readings.

A 985mb pressure reading " could, emphasis on could" give a pressure-wind relationship maximum possible wind speed of 90mph. If Dolly were well formed and a lot more efficent in the tropical meterology department.

At this time Dolly is attempting to consolidate again.

For those of you viewing the HDOB messages. AF 308 is preparing to take off from Keesler. They transmitted a test SMFR wind speed of 87 knots. This is a test and not an actual wind speed.


danielwAdministrator
(Moderator)
Tue Jul 22 2008 03:32 AM
Warnings are UP

TROPICAL STORM DOLLY ADVISORY NUMBER 7
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042008
1000 PM CDT MON JUL 21 2008

...HURRICANE WARNINGS ISSUED...

AT 10 PM CDT...0300 UTC...A HURRICANE WARNING HAS BEEN ISSUED FROM
BROWNSVILLE TO PORT O'CONNOR TEXAS. A HURRICANE WARNING MEANS THAT
HURRICANE CONDITIONS ARE EXPECTED WITHIN THE WARNING AREA WITHIN
THE NEXT 24 HOURS. PREPARATIONS TO PROTECT LIFE AND PROPERTY
SHOULD BE RUSHED TO COMPLETION.

AT 10 PM CDT...A TROPICAL STORM WARNING HAS BEEN ISSUED FROM NORTH
OF PORT O'CONNOR TO SAN LUIS PASS. A TROPICAL STORM WARNING MEANS
THAT TROPICAL STORM CONDITIONS ARE EXPECTED WITHIN THE WARNING AREA
WITHIN THE NEXT 24 HOURS.

AT 10 PM CDT...THE GOVERNMENT OF MEXICO HAS ISSUED A HURRICANE
WARNING FROM RIO SAN FERNANDO NORTHWARD TO THE BORDER BETWEEN
MEXICO AND THE UNITED STATES.

AT 10 PM CDT...THE GOVERNMENT OF MEXICO HAS ISSUED A TROPICAL STORM
WARNING AND A HURRICANE WATCH FROM LA PESCA TO SOUTH OF RIO SAN
FERNANDO. A HURRICANE WATCH MEANS THAT HURRICANE CONDITIONS ARE
POSSIBLE WITHIN THE WATCH AREA...GENERALLY WITHIN 36 HOURS.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...INCLUDING POSSIBLE
INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED
BY YOUR LOCAL WEATHER OFFICE.


scottsvb
(Weather Master)
Tue Jul 22 2008 03:35 AM
Re: HDOB Wind Speeds

There is no "EYE" in dolly right now....we dont need to over hypecast the nowcasting of this system. Its just a center of circulation and not a "EYE". There was no pressure also of 985mb... latest has it at 999mb or a 50-60mph storm.. Still conditions are perfect for further strengthning tonight into tomorrow. I do feel though even though Dolly will slow some.. she will make landfall earlier than expected tomorrow night as a Cat 1 or maybe weak 2 in extreme NE MX but Brownsville will deal with near hurricane force winds as forecasted by the NHC.

cieldumort
(Moderator)
Tue Jul 22 2008 03:47 AM
Re: HDOB Wind Speeds

Yeah, this 985 can be tossed out. It's sitting in between some other pressure extraps that were in the high 990s. The wind measurement is supposedly a mere 10-second average at flight level, so I'm not sure what to make of that, other than at least it is a little believable.. perhaps they flew through a tight little meso, etc. etc., etc.

I do take some issue with the "NO EYE" meme going around, however. Clearly, there is an attempt to sync up the MLC and LLC, and should/once this complete, based on some of the more recent microwave passes, it shouldn't take long at all for an eyewall to complete forming. You can see for yourself in the Composite, 37V, 85H ranges in particular that thunderstorm banding is tightening up quite well.


typhoon_tip
(Meteorologist)
Tue Jul 22 2008 04:39 AM
Re: HDOB Wind Speeds

Quote:

There is no "EYE" in dolly right now....we dont need to over hypecast the nowcasting of this system. Its just a center of circulation and not a "EYE". There was no pressure also of 985mb... latest has it at 999mb or a 50-60mph storm.. Still conditions are perfect for further strengthning tonight into tomorrow. I do feel though even though Dolly will slow some.. she will make landfall earlier than expected tomorrow night as a Cat 1 or maybe weak 2 in extreme NE MX but Brownsville will deal with near hurricane force winds as forecasted by the NHC.




There is no eye just yet. The NHC is finally admitting that east shear has been impacting the system, after stating all day that anticyclonic upper levels covered the entire western Gulf area.

That said, there is an apparent tendency to wrap convection squarely around a central core. The low level center, however, is stated to be south of the mid level vortex. This is consistent with an earlier post I made regarding an apparent tilted system. The TUTT is the culprit. Even at this hour, that feature still lingers in the southern BOC. From the Yuk Pen areas and proceeding to the "core" there is still the presence of shear, though it is decreasing.

The most recent frames suggest a somewhat more NW motion with the IR...thus mid-level. It seems more likely to me that rapid intensification is still iffy. The storm is crossing some impressive oceanic thermal content, and a battle between TC thermodynamics and negative mechanics is underway. Tough call. Could have a big deepening system if the shear were to relax entirely, but the existence of shear is off-setting to some degree.

I'm more concerned about a slow down, where by the system develops strongly ...over guidance, within reach of shores. Monitoring of this system from the middle TX Bend down into Mexico, obviously highly warranted.


Storm Hunter
(Veteran Storm Chaser)
Tue Jul 22 2008 05:27 AM
Re: HDOB Wind Speeds

AF Recon is going through Dolly right now...

and i agree with others... that the TUTT over SBOC could have caused the disruption to Dolly... which is a good thing... keeping it weaker.. but as other's have noted.. i think the surface and mid level are about to hook up and Dolly is going to make a run at becoming a hurricane in the next 12hrs.. its looking better with time now... and i do think Dolly is starting to slow in forward speed... I REALLY THINK the G-IV data from this afternoon was what finally made NHC/HRD say that the upper levels weren't really perfect... but were close...

FOR THOSE INTERESTED... here's what i was thinking.. and a good drawing by Dr. Jeff Masters proves it..
Dry air from the Yucatan, thanks to the TUTT


Quote:

For those of you viewing the HDOB messages. AF 308 is preparing to take off from Keesler. They transmitted a test SMFR wind speed of 87 knots. This is a test and not an actual wind speed.




I think from what i heard... that when they turn on the SMFRt on in the back... and its not meant to be used over land... its actually getting the airspeed to the aircraft... the waves are hitting land and caculating aircraft speed?


Storm Hunter
(Veteran Storm Chaser)
Tue Jul 22 2008 05:38 AM
Re: HDOB Wind Speeds

wow... seems like Dolly is still trying to get its act together. I think the surface center is to the north of 23.17N

Flight LEVEL center appears to still be off from surface center by just a little bit.

Time:
05:27:30Z
Coordinates:
23.17N 93.27W
Acft. Static Air Press:
843.2 mb (~ 24.90 inHg)
Acft. Geopotential Hgt:
1,485 meters (~ 4,872 feet)
Extrap. Sfc. Press:
999.9 mb (~ 29.53 inHg)
D-value:
-
Flt. Lvl. Wind (30s):
From 91° at 0 knots (From the E at ~ 0.0 mph)
Air Temp:
18.0°C (~ 64.4°F)
Dew Pt:
14.0°C (~ 57.2°F)
Peak (10s) Flt. Lvl. Wind:
2 knots (~ 2.3 mph)
SFMR Peak (10s) Sfc. Wind:
0 knots (~ 0 mph)
SFMR Rain Rate:
5 mm/hr (~ 0.20 in/hr)


Storm Hunter
(Veteran Storm Chaser)
Tue Jul 22 2008 05:41 AM
Re: HDOB Wind Speeds

they dropped in the center.. data just came in...

pressure at 999mb? Did notice its 80.6 degrees at the surface.

Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 308)
Storm Number: 04
Storm Name: Dolly (in the North Atlantic basin)
Mission Number: 13
Observation Number: 06
Date: Near the closest hour of 5Z on the 22nd day of the month
Highest Mandatory Level For Which Wind Was Reported: 850mb
Coordinates: 23.2N 93.3W CENTER?
Location: 324 miles (521 km) to the SE (126°) from Brownsville, TX, USA.

Average Wind Over Lowest Available 150 geopotential meters (gpm) of the sounding:
- Lowest 150m: 152 gpm - 2 gpm (499 geo. feet - 7 geo. feet)
- Wind Direction: 160° (from the SSE)
- Wind Speed: 6 knots (7 mph)


cieldumort
(Moderator)
Tue Jul 22 2008 08:35 AM
Re: Hurricane Warnings Up in Texas Brownsville to Port O'Connor

Middle of the night and it appears that finally the ULL to Dolly's southwest is filling in a little bit more and continuing west at around the same pace or even a touch faster, while Dolly's forward motion is slowing down, and perhaps even starting to trend WNW once again.

This development has greatly lessened the shear and infiltration of dry air within Dolly's southern half. With outflow starting to improve now in this area, along with the increased overall moisture content, convection is currently taking off - and taking off from what looks like right over the LLC - making for an almost regular CDO-type scene.

The most recent vort fix, that was made just about the time conditions started turning more favorable, found:

Estimated Max Surface Winds 48.6KT (55.9mph 90.0km/h) *
Position of the center: 23° 14' N 093° 28' W (23.2°N 93.5°W)
Minimum pressure: 997mb (29.44in)

It appears that Dolly has entered a sweet spot, for now. That SSTs are not as warm ahead becomes almost irrelevant, given the much-improved atmospheric environment. As a deepening cyclone, she may begin to respond to a slight developing weakness in the mid-level high to her north, and complete that trip to the Texas coastline. Otherwise, a continued westerly track will place landfall somewhere between Tampico, Mx and Brownsville, but which would still keep a sizable portion of the RFQ along the south Texas shoreline.


Random Chaos
(Weather Analyst)
Tue Jul 22 2008 11:52 AM
Re: Hurricane Warnings Up in Texas Brownsville to Port O'Connor

Recon is in the storm again. Several HDOB messages estimate surface pressure down to 990mb. No vortex recon yet, but from winds, looks like they went through the flightlevel center. Not sure they got the surface center, though.

Edit: Dropsonde right next to those HDOB readings got 993 surface pressure with a surface temperature of 79.9F.

Storm structure: We also had a microwave overpass about 4 hours ago that shows fairly strong internal structure, but at that time, still no eye development.

Edit 2: Per vortex recon, Dolly has 993mb pressure and a poorly defined elliptical eye. No temperature gradient across the eyewall (54F at altitude inside and outside). Size is 15nm x 7nm.


berrywr
(Weather Analyst)
Tue Jul 22 2008 12:55 PM
Re: Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Port O'Connor

TUTT is still impairing outflow on the storm's south and west side; though the channel on the other side looks remarkably well. Satellite imagery at this time shows a CDO, though small developing; NOAA plane currently in the storm indicates a ragged eye and I agree, once the TUTT is out of the way, the stage is set for rapid intensification given SSTs, warm eddy approaching, and upper air all indicate "green" for Dolly to wind up before landfall. As in all intensity forecasting; how much with whatever time it has left over water.

MikeCAdministrator
(Admin)
Tue Jul 22 2008 12:58 PM
Re: Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Port O'Connor

I'll be recording a few webcams/radars for Dolly

Let me know if you would like to see something else.

Currently (not all will be "turned on" until later):

Dolly Brownsville Level 3 Radar (Now Active)
Long Range Radar (Now Active)
South Padre Island Surf Cam -- High Res (Not Active Yet)
South Padre Island Bay Cam (Now Active)

I'll be turning these on and off during the day, and leaving them on when Dolly approaches.

The main page article has a list of radars, media, and cams toward the bottom.

And 97L is now being tracked (That wave far off Africa)


cieldumort
(Moderator)
Tue Jul 22 2008 02:04 PM
Re: Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Port O'Connor

"Hurricane Dolly" looks to be a lock, but several things are arguing against Dolly being able to enter a period of very rapid intensification.. especially as that would pertain to RI to beyond Cat 2.. without a lot of luck.

After the overnight easing from the gnawing jaws of the TUTT (ULL) to Dolly's southwest, it appears that some shearing has begun again. This is perhaps the number one reason why Dolly has been unable to establish much of an eye, despite repeated attempts.

Unless the TUTT pulls away at a more rapid pace than this, which at this time looks possible, but less and less so, it's going to be all up to the forward speed of Dolly as to whether or not this situation continues to inhibit her development going forward.

Something of a blocking pattern is in place from the east pac running up through old Mexico and onward into Texas, which is in status quo with a mid-upper level trof over west Texas, and a mid-level ridge in the east. Right now, unless some part of this train wreck gives way, Dolly may soon also start taking on more shear from her west. (A little bit of westerly shear has been an on again, off again presence for the last 24 hours or so, but has usually been masked by the outflow wrapping around from there).

SSTs are not going to ramp up in any meaningful way along her expected course. In fact, with Dolly now at about 24N 94W, she'll be traveling over a negative anomaly, or cool eddy. From there, TCHP still does not increase much, at all. While the depth of the 26C water is plenty deep for a passing Cat 3 hurricane traveling fast, Dolly is still expected to slow down, and the upwelling that would likely occur from a slow-moving Cat 1-2 hurricane over 26C water of these depths tends to preclude rapid development much beyond Cat 2 (Not applicable if Dolly does not slow down so much).

Finally, there's simply only so much water left. That coastline is coming up mighty fast, and then it's curtains.


WeatherNut
(Weather Master)
Tue Jul 22 2008 03:05 PM
Re: Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Port O'Connor

There is that fine line between a ULL that shears and one that ventilates, and seeing how some outflow is getting started on the south/southwest side, we might be approaching that line. The ULL seems to still be moving west and with Dolly moving NW as per 11am NHC discussion this might become a help not a hindrance

Rich B
(British Meteorologist)
Tue Jul 22 2008 05:06 PM
Re: Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Port O'Connor

Looking at radar out of Brownsville, and it shows the 1st real rain band moving onshore along the upper Mexico coast, and just about to move onshore near Brownsville. While radar shows the eyewall, visible imagery doesnt really show much in the way of an eye just yet. In fact, radar imagery shows the eyewall convection to be not that strong. Dolly has chance to strengthen more, and will no doubt become a hurricane, but given the presentation and the time remaining over water, looks like she isnt gonna get 'that' strong! Also, with the continued northwest motion evident on the radar, she looks likely to make landfall near the TX / MX border, or just to the south.

MikeCAdministrator
(Admin)
Tue Jul 22 2008 05:40 PM
Re: Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Port O'Connor

Webcam recordings (now w/ radar):

South Padre Island (Bay Side)
South Padre Island (Gulf Side)


WeatherNut
(Weather Master)
Tue Jul 22 2008 07:03 PM
Attachment
Re: Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Port O'Connor

The eye is starting to clear on the last frame of visible SAT image. I t jives with the radar fixes

Beaumont, TX
(Storm Tracker)
Tue Jul 22 2008 07:11 PM
Re: Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Port O'Connor

Is that an eye we are seeing? She looks a bit stronger. Hoping we will get a little rain. We are hoping it won't be too bad for our neighbors
in South Texas.


scottsvb
(Weather Master)
Tue Jul 22 2008 07:23 PM
Re: Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Port O'Connor

Center of Circulation....... A "EYE" is a well identified center of circulation on all 3 spectrums... Radar, Visible, and Infrared satellite appearence... Dolly has just radar signature of 1.. the sats show some drier air mixed in but the system but, is getting more and more organized into a Hurricane right now.... A actual eye may form later tonight or tomorrow when the system gets stronger.

Clark
(Meteorologist)
Tue Jul 22 2008 07:58 PM
Re: Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Port O'Connor

No, that's an eye there alright -- recon sure confirms it in their vortex reports and microwave satellite imagery show it developing earlier today as well:



Dolly is moving along a gradient of oceanic heat content right now, avoiding a cool eddy to its south and a warm eddy to its north:



It is along these gradients where storms seem to try to intensify at a fairly rapid clip, likely due to the enhanced flux potential the gradients provide. With waters sufficiently warm to provide ample oceanic heat to the storm, the only thing that should constrain Dolly's intensification should be landfall sometime tomorrow very near Brownsville. I'd place my bets in the high-end category 2 range with a little bit of wiggle room in either direction.


Storm Hunter
(Veteran Storm Chaser)
Tue Jul 22 2008 08:24 PM
Attachment
Re: Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Port O'Connor

wow... never seen super resolution radar from level II data on a tropical system... Going to come in handy tonight when tornados start spining up! nice eyewall starting to show up

typhoon_tip
(Meteorologist)
Tue Jul 22 2008 08:35 PM
Re: Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Port O'Connor

Quote:

No, that's an eye there alright -- recon sure confirms it in their vortex reports and microwave satellite imagery show it developing earlier today as well:

...

Dolly is moving along a gradient of oceanic heat content right now, avoiding a cool eddy to its south and a warm eddy to its north:

...

It is along these gradients where storms seem to try to intensify at a fairly rapid clip, likely due to the enhanced flux potential the gradients provide. With waters sufficiently warm to provide ample oceanic heat to the storm, the only thing that should constrain Dolly's intensification should be landfall sometime tomorrow very near Brownsville. I'd place my bets in the high-end category 2 range with a little bit of wiggle room in either direction.




Agreed, eye. This is also coming into clarity over at TPC and the IR channels rather nicely... Looks like a real attempt a better structured CDO is about to take place, as well, as there is a rather abrupt tendency to explode very cold cloud tops around the SW flank of the developing eye-wall.


ShanaTX
(Storm Tracker)
Tue Jul 22 2008 09:00 PM
Re: Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Corpus Christi

Does this report mean Dolly's a hurricane? Or does someone have to actually release the 5pm advisory first?

Also... to me it looks like it's going to have to make a sharp westward turn to hit Mexico... Looking more and more like South Texas.

'shana

The NHC is the only one who can make that call but at times you can read between the lines...


Storm Hunter
(Veteran Storm Chaser)
Tue Jul 22 2008 09:05 PM
Attachment
Re: Dolly Strengthening.. Hurricane Warnings Up in Texas Brownsville to Corpus Christi

pressure is 986mb now... more to come in a second

Now its Hurricane Dolly... upgrade coming out now

from last vortex... recon heading home
Minimum Sea Level Pressure: 986mb (29.12 inHg)
Maximum Flight Level Temp & Pressure Altitude Outside Eye: 10°C (50°F) at a pressure alt. of 3,048m (10,000ft)
Maximum Flight Level Temp & Pressure Altitude Inside Eye: 13°C (55°F) at a pressure alt. of 3,050m (10,007ft)

Maximum Flight Level Wind: 72kts (~ 82.9mph) in the northeast quadrant at 20:29:30Z
Distance of Surface Center From Flight Center: Surface center is within 5 nautical miles of flight center.


and if i am correct.. Dolly is dropping a 1mb an hour right now?

**Side note... my homeboy Kermit is up and on his way to dolly... (i got to tour N42RF back in the spring... the only plane to hit high G's in Felix and in Hugo)*** attached is a pic i took of N42RF



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