ATL: DOLLY - REMNANTS - Discussion

[beoumont]

Something's happening here:



What it is ain't exactly clear:

[Alyono]

the surface feature may be closer to 91W

[Hammy]

rotation looks to be about 93-94 and at the speed it's moving likely inland within 24 hours; I have a feeling the recon mission is going to be cancelled once the sun comes up.

[cycloneye]

The Brownsville NWS made a good discussion about how 99L/TD?/TS? may increase the moisture for South Texas.

.LONG TERM.../TUESDAY NIGHT THROUGH SUNDAY/...THE MAIN CONCERN IN
THE LONGER RANGE PERIOD WILL BE THE EVENTUAL TRACK AND DESTINATION
OF THE SURFACE LOW NOW EMERGING OFF OF THE YUCATAN PENINSULA
HEADING TO THE WEST NORTHWEST PUSHING ACROSS THE SOUTHWESTERN
GULF OF MEX. THE BULK OF THE LONGER RANGE MODEL GUIDANCE WANTS TO
KEEP THIS FEATURE ON A GENERAL WEST NORTHWEST TRACK WITH THE
CENTER MOVING INLAND ROUGHLY NEAR THE TAMPICO AREA TUES
NIGHT/EARLY WEDNESDAY MORNING. THIS WEST NORTHWEST MOVEMENT IS
MAINTAINED THROUGH THE NEXT COUPLE OF DAYS AS BROAD 500 MB RIDGING
BUILDS OVER THE SOUTHERN STATES. IF THIS SURFACE LOW REMAINS
FAIRLY BROADLY ORGANIZED WITH A LARGE SWATH OF DEEPER LAYER TROPICAL
MOISTURE ASSOCIATED WITH IT THEN A FAIRLY BROAD AREA OF TROPICAL
RAINS WILL LIKELY SPREAD ACROSS DEEP SOUTH TX AND NORTHEASTERN
MEXICO RESULTING IN MORE WIDESPREAD RAINFALL TOTALS. IF THE SYSTEM
BECOMES BETTER ORGANIZED AS IT TRACKS ACROSS THE SOUTHWESTERN
GULF THEN THE BULK OF THE PCPN MAY BE MORE CONCENTRATED FURTHER
SOUTH WHICH WOULD MISS MUCH OF THE RGV. AT THIS TIME AM GOING WITH
THE SCENARIO WITH A MORE BROADLY DEFINED SURFACE LOW/TROUGH WHICH
WOULD RESULT IN BETTER CONV CHCS FOR THE REGION.

THE ECMWF AND GFS POPS ARE FAIRLY SIMILAR IN INCREASING POPS TUES
NIGHT THROUGH THURS AS THE TROPICAL MOISTURE ASSOCIATED WITH THE
BROAD SURFACE LOW SURGES WEST AND NORTHWEST OVER THE REGION
THROUGH MID WEEK. THE DEEPER LAYER MOISTURE VALUES START TO
DIMINISH GRADUALLY OVER THE AREA AS THE WEEKEND APPROACHES AND
WILL GRADUALLY TREND DOWN THE CONV CHCS INTO NEXT SATURDAY AND
SUNDAY AS THE DEEP LAYER TROPICAL MOISTURE FEED SHIFTS WEST AND
NORTH AROUND THE WEST SIDE OF THE SOUTHERN 500 MB RIDGE AXIS.

SINCE THE LONGER RANGE MODEL GUIDANCE IS IN PRETTY GOOD AGREEMENT
IN THE HANDLING OF THIS TROPICAL DISTURBANCE HAVE OPTED TO GO WITH
A GENERAL MODEL BLEND OF THE ECMWF AND THE GFS FOR BOTH POPS AND
TEMPS THROUGH DAY 7. THE MAX TEMPS WILL LIKELY BE SUPPRESSED A BIT
WED ADN THURS AS THE CONV CHCS MAX OUT OVER THE AREA. WILL THEN
TREND THE TEMPS UP A BIT LATER AS THE CONV CHCS FADE A BIT AND A
LITTLE MORE DIURNALY HEATING IS EXPECTED DURING THE AFTERNOON
HOURS.

OVERALL CONFIDENCE IN THE LONGER RANGE FORECAST WORDING IS ON THE
INCREASE AS THE MODEL GUIDANCE STARTS TO GEL TOWARDS A SIMILAR
SOLUTION. RUN TO RUN CONSISTENCY WITH THE GFS MEX MOS HAS ALSO
BEEN PRETTY STABLE OVER THE LAST SEVERAL RUNS KEEPING THE HIGHEST
POPS FOR WED AND THURS.

[cycloneye]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT MON SEP 1 2014

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

A broad area of low pressure is located over the eastern Bay
of Campeche. Environmental conditions appear to be favorable for
some development, and this system could become a tropical depression
within the next day or two as it moves west-northwestward near 10
mph. An Air Force Reserve reconnaissance aircraft is scheduled to
investigate the low this afternoon, if necessary. Regardless of
development, this system will produce heavy rainfall across the
Yucatan Peninsula and southeastern Mexico today and Tuesday, and
across portions of eastern mainland Mexico on Tuesday and Wednesday.
* Formation chance through 48 hours...high...60 percent.
* Formation chance through 5 days...high...70 percent.

$$
Forecaster Pasch

[cycloneye]

12z Best Track.

AL, 99, 2014090112, , BEST, 0, 192N, 920W, 25, 1009, LO

[wxman57]

00Z Euro remains quite consistent in taking the center inland near Tampico in just over 24 hours. GFS is much slower (like never inland). I don't trust it. Not much time for development, but should be at least a TD by noon tomorrow.

[cycloneye]

00Z Euro remains quite consistent in taking the center inland near Tampico in just over 24 hours. Not much time for development, but should be at least a TD by noon tomorrow.

Even if it tracks to near Tampico,will the South Texas folks get plenty of rain from this?

[Sanibel]

Edit: That satellite shot is deceptive. The surface feature is offshore meaning the convection is displaced which indicates a less organized storm. In any case this is still the best organized Gulf system yet.

[tropicwatch]

Most recent visible loop:

http://weather.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20CONUS&lat=20&lon=-90&type=Animation&info=vis&numframes=15

[Alyono]

near 19.5N and 93W

convection is trying to fire near the center, but there appears to be some shear as it is being blown away quickly and we also have the suppressive Kelvin wave

conditions are marginal at best. I agree that a TD or a weak TS may form. However, highly unlikely that anything more comes from this. Again, the 1980s way of thinking favorable conditions = low shear is not the way to go. We are learning far more about what favorable conditions are. One must include planetary waves

[wxman57]

I don't see anything for recon to investigate at the moment. They should cancel for today. Development is more likely going to be tonight/tomorrow.

[SouthDadeFish]

I don't see anything for recon to investigate at the moment. They should cancel for today. Development is more likely going to be tonight/tomorrow.

I agree. Doesn't look like too much is going on at the moment.

[hurricanehunter69]

My money is definitely on development(Dolly). Simply based on it's very favorable location and forward motion(only 10 mph). Although I wouldn't bet on it....I'm interested to see if we can bat a thousand(4/4) on the Hurricane front.

[MGC]

Looked more impressive to me yesterday evening while it was over the Yucatan. Not much convection near the low center this morning. Rather familiar theme this season.....might make it to a weak TS by the time it hits land....happy Labor Day everyone.....MGC

[tropicwatch]

HH finding TS strength winds but heavy rain rate.

[srainhoutx]

HH finding TS strength winds but heavy rain rate.

Well NNW of Merida, MX.

[cycloneye]

Plane is decending. Let's see if they can find a closed LLC.

[tropicwatch]

GE is now reporting plane position if someone wants to post graphics on recon.

[tolakram]

live visible loop: http://wwwghcc.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20CONUS&lat=21&lon=-92&info=vis&zoom=1&width=1200&height=720&quality=95&type=Animation&palette=ir1.pal&numframes=20