2011 ATL Hurricane Season: Coming to an End

[wxman57]

Lots of uncertainties. GFS is the slowest of the models with the system, probably too slow. Trend is toward a slightly stronger ridge over TX/LA by later next week. That would mean a threat to northern Mexico or the lower TX coast vs. up here. I'm thinking 40% development chances next Mon-Wed. Probably will flare up considerably just before moving into the Yucatan late Saturday.

[unome]

from the gridded marine forecast http://www.nhc.noaa.gov/marine_forecasts.shtml

http://www.nhc.noaa.gov/tafb/gridded_ma ... 9_1200.png

http://www.nhc.noaa.gov/tafb/gridded_ma ... 9_1200.png

animate them at the 1st link above

[Andrew]

00z GFS is even slower this run and sits it over the Yucatan. If that happens you could see the LLC relocate north of the Yucatan as the GFS has been possibly showing some of the deeper convection occurring there.

[srainhoutx]

Regarding the Western Caribbean wave. The model trends over night have been to slow everything down, development wise. The GFS, UKMET has slowed even further and are the slowest to develop any system in the BoC. The Euro, Canadian and Nogaps tend to be the furthest S with the Euro and Nogaps slowing things down a tad as well. The Canadian suggests a bit quicker development and brings it onshore S of Tampico on Wednesday. Interesting that a slower development may allow for a bit further N migration as a weakness in the Ridge is suggested later next week. My hunch is this may take awhile to spin up, if it does at all and would be a fairly large area of disturbed weather. Much like what we saw last year with Alex. We will see.

[wxman57]

Model trends overnight are weaker and farther south into Mexico with this disturbance. 6Z GFS dropped development, leaving only the Canadian bullish on development. I'm still thinking it may have a far shot of spinning up just before moving into the Yucatan tomorrow then again in the SW Gulf/BoC Mon/Tue. I'd put any landfall down near Tampico, maybe even farther south next Thursday/Friday. Think "Bret" of 2005 vs. "Arlene".

[srainhoutx]

HPC morning update re: the Upper Ridge:

OVER THE PAST FEW DAYS...THE STRENGTH OF THE SUBTROPICAL RIDGE
OVER THE SOUTHERN PLAINS HAS BEEN SLOWLY WEAKENING WITHIN THE
FORECAST GUIDANCE...MOST DRAMATICALLY WITHIN THE ECMWF SOLUTION.
STILL...HIGHS BETWEEN 100 AND 110 ARE EXPECTED ACROSS INTERIOR
PORTIONS OF TEXAS AND OKLAHOMA THROUGH THE PERIOD.

[srainhoutx]

Like the 06Z run, the 12Z GFS suggests a weak area of low pressure buried in the BoC.

[tireman4]

If Wxman57 says it aint gonna happen, that is enough for me. He buys it, I am buying it, ( something for the Upper Texas Coast)...rain or otherwise from this well it could be, maybe, storm forming or not.

[srainhoutx]

Like the 06Z run, the 12Z GFS suggests a weak area of low pressure buried in the BoC.

Or not...

[srainhoutx]

Of course the Canadian blows up a Hurricane...

[srainhoutx]

It looks like the 12Z Euro has this weak disturbance moving fairly quickly and a bit further N in the Bay of Campeche/SW Gulf.

[wxman57]

12Z GFS doesn't develop THIS disturbance but then tries to develop something else in the BoC NEXT weekend. Yeah, right. Canadian now has a much weaker low moving inland into Mexico on Tuesday vs. Thursday from earlier runs. I think the trend is toward no development and no threat to Texas.

[srainhoutx]

So much for that slowing down idea near the Yucatan over the weekend. The good news is the potential rainfall for S TX and NE Mexico. HPC afternoon Update:

RAINFALL MAGNITUDE/CHANCES ACROSS SOUTHERN TEXAS REMAIN A QUESTION
MARK MID TO LATE NEXT WEEK...DEPENDENT UPON DEVELOPMENTS IN THE
WESTERN CARIBBEAN/SOUTHERN GULF OF MEXICO. WHILE THERE HAS BEEN A
SOUTHERLY TREND IN THE DETERMINISTIC GFS/CANADIAN
GUIDANCE...ENOUGH 00Z ENSEMBLE MEMBERS /NEARLY ONE-QUARTER OR 20
OF THE 90/ MOVE THE LOW INTO SOUTHERN TEXAS LATE IN THE PERIOD SO
A TEXAS LANDFALL SCENARIO CANNOT BE RULED OUT. THE 17Z
COORDINATION CALL WITH NHC SPED THIS SYSTEM UP SOMEWHAT FROM
YESTERDAY AND KEPT THIS SYSTEM MOVING FAR ENOUGH TO THE SOUTH THAT
SCATTERED SHOWERS/THUNDERSTORMS REMAIN POSSIBLE IN SOUTHERN TEXAS
LATE NEXT WEEK.

[wxman57]

Yep, less chance of development and more time over southern Mexico and Central America. The reason the HPC mentions rain chances in south TX is if the disturbance tracks in that direction as those ensemble members forecast. Chances are they're wrong, though. Good weekend to head over to Discovery Green to see the "world's largest sprinkler" in action!

[srainhoutx]

Pressures have lower across the Western Caribbean and the Southern Gulf and now the numerical models are suggesting a spin up closer to the 4th of July Holiday weekend. One thing is certain, moisture has increased in the Western Basin and yet another tropical wave will approach the Caribbean on Monday. Meanwhile the Western Caribbean activity is spreading WNW and should be over the Yucatan during the weekend...

[srainhoutx]

Looks like just a hint of mid level spin along the wave axis via NASA HI RES VIS Imagery in the NW Caribbean.

HPC:

FOR INTERESTS ALONG THE GULF
COAST...THE COORDINATION WITH NHC RESULTED IN ANY TROPICAL SYSTEM
STAYING NEAR THE GULF OF CAMPECHE FOR THIS FORECAST.

[srainhoutx]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT SAT JUN 25 2011

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

A TROPICAL WAVE INTERACTING WITH AN UPPER-LEVEL TROUGH IS PRODUCING
WIDESPREAD CLOUDINESS AND SCATTERED SHOWERS OVER MUCH OF THE
WESTERN CARIBBEAN SEA...HONDURAS...AND NICARAGUA. TROPICAL CYCLONE
FORMATION IS UNLIKELY WHILE THE WAVE INTERACTS WITH THE UPPER-LEVEL
TROUGH...AND WITH CENTRAL AMERICA AND THE YUCATAN PENINSULA.
HOWEVER...THIS SYSTEM IS EXPECTED TO EMERGE OVER THE BAY OF
CAMPECHE IN A COUPLE OF DAYS WHERE UPPER-LEVEL WINDS ARE FORECAST
TO BECOME A LITTLE MORE CONDUCIVE FOR SOME DEVELOPMENT TO OCCUR.
THERE IS A LOW CHANCE...10 PERCENT...OF THIS SYSTEM BECOMING A
TROPICAL CYCLONE DURING THE NEXT 48 HOURS. REGARDLESS OF
DEVELOPMENT...THIS DISTURBANCE COULD BRING LOCALLY HEAVY RAINFALL
AND GUSTY WINDS TO THE YUCATAN PENINSULA...BELIZE...AND ADJACENT
CARIBBEAN WATERS DURING THE NEXT DAY OR TWO AS IT MOVES
WEST-NORTHWESTWARD AT 10 TO 15 MPH.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER STEWART

[Ptarmigan]

I don't care if it develops or not. We really need rain.

[biggerbyte]

Agreed

[srainhoutx]

Up to 20% this morning...

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT SUN JUN 26 2011

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

A TROPICAL WAVE IS PRODUCING CLOUDINESS AND DISORGANIZED SHOWER
ACTIVITY OVER HONDURAS...NICARAGUA...AND THE NORTHWESTERN CARIBBEAN
SEA. LITTLE IF ANY DEVELOPMENT IS EXPECTED AS THE WAVE MOVES ACROSS
CENTRAL AMERICA AND THE YUCATAN PENINSULA TODAY. HOWEVER...THIS
SYSTEM IS FORECAST TO EMERGE OVER THE BAY OF CAMPECHE ON MONDAY
WHERE UPPER-LEVEL WINDS ARE EXPECTED TO BECOME CONDUCIVE FOR SOME
DEVELOPMENT TO OCCUR. THERE IS A LOW CHANCE...20 PERCENT...OF THIS
SYSTEM BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.
REGARDLESS OF DEVELOPMENT...THIS DISTURBANCE COULD BRING PERIODS OF
LOCALLY HEAVY RAINFALL AND GUSTY WINDS TO PORTIONS OF EASTERN
MEXICO AND CENTRAL AMERICA DURING THE NEXT DAY OR TWO AS IT MOVES
WEST-NORTHWESTWARD AT 10 TO 15 MPH.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER LANDSEA/PASCH