June: Onshore Flow Returns With Increasing Gulf Moisture

[weatherguy425]

Great Just out of HGX...

MONSTROUS RIDGING ENVELOPES THE
U.S. PLAINS NEXT WEEKEND THAT WILL NOT ONLY SHUNT/SUPPRESS ANY
TROPICAL ACTIVITY FURTHER SOUTH BUT ALSO SHUT DOWN ANY PRECIPITATION.
AFTER AN ON-AND-OFF AGAIN SHOWERY START TO THE WEEK...IT MAY VERY
WELL END HOT AND DRY (PRECIP-WISE). 31

[gocuse22]

Got bored, decided to make a Houston Weather twitter.

It will be updated several times a day.

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https://twitter.com/#!/HouTX_Weather

[PA&HOUwx]

Long range GFS has a massive ridge developing in the 8-16 day timeframe. Just perfect, of course it would be scorching hot as soon as I get down there

[srainhoutx]

Showers/storms associated with a weak mid level easterly wave/trough are just to our E across SW Louisiana this morning. That trough axis will continue to move W into the Coastal Texas area tonight bringing increased moisture and PW's of nearly 2.0+ inches and increasing rain chances into Tuesday/Wednesday.


The overnight medium range guidance has switched back to suggesting the upper ridge will not be a strong allowing for a broad low pressure disturbance to form in the Bay of Campeche and meander N to NNW toward the NE Mexico/South Texas Coastal areas late this coming weekend into early the following week. In fact the 00Z Euro suggests a bit more develop low approaching the Brownsville/Corpus Christi area on this coming Sunday. Satellite imagery suggests a developing area of disturbed weather in the EPAC sliding E and another area in the Western Caribbean. Plentiful tropical moisture continues to build along and S of the monsoonal trough draped across Mexico to our S. Most reasonable medium range guidance continue to suggest a broad area of disturbed weather in the SW Gulf will allow for moisture to be drawn N across the NE Mexico/ Lower Texas Gulf Coast during the week. All eyes will be on that disturbance as we head later into the work week. Stay tuned!

[Rip76]

Yay (sarcasm)

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
358 AM EDT MON JUN 18 2012

MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA
AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W.

GULF OF MEXICO...
THE WEAK SURFACE TROUGH THAT HAD BEEN MOVING THROUGH THE NW GULF
APPEARS TO HAVE DAMPENED OUT AS OF 18/06Z. THIS LEAVES A SURFACE
RIDGE EXTENDING FROM THE CAROLINAS TO THE SW GULF WITH GENERALLY
LIGHT TO MODERATE SE WINDS OVER THE ENTIRE GULF. THE EXCEPTION IS
THE STRAITS OF FLORIDA WHERE 15 TO 20 KT EAST WINDS ARE NOTED.
SCATTERED SHOWERS AND A FEW THUNDERSTORMS LINGER OVER THE N
CENTRAL GULF...ON THE NORTH EDGE OF THE LOOP CURRENT AND UNDER AN
AREA OF UPPER DIVERGENCE. DRIER MID AND UPPER LEVEL AIR MOVING
INTO THIS AREA WILL INHIBIT CONVECTION THROUGH THE REMAINDER OF
THE DAY. THE PRES GRADIENT WILL TIGHTEN OVER THE EASTERN AND
CENTRAL GULF TUE BETWEEN THE HIGH PRES OVER THE CAROLINAS AND A
TROUGH MOVING TOWARD THE YUCATAN ACROSS THE NW CARIBBEAN. THE GFS
REMAINS THE STRONGEST SOLUTION SHOWING WINDS TO 25 KT OVER THE
EASTERN AND CENTRAL GULF THROUGH THU. THE ECMWF AND UKMET ON THE
OTHER HAND INDICATE WINDS INCREASING BUT STAYING IN THE 15 TO 20
KT RANGE. THE GFS HAS BEEN TRENDING WEAKER SHOWING THE AREA OF
FRESH TO STRONG WINDS DECREASING SOMEWHAT COMPARED TO EARLIER
RUNS AND IS MORE IN LINE WITH THE OTHER MODELS. THE FORECAST
FAVORS THE ECMWF/UKMET SOLUTIONS THROUGH THU. BOTH THE GFS AND
ECMWF SHOW AN AREA OF LOW PRES EMERGING OFF THE YUCATAN INTO THE
S CENTRAL GULF BY LATE THU...FURTHER EAST THAN EARLIER
RUNS...THEN SHIFTING WESTWARD TOWARD THE SW GULF FRI. THE
OFFICIAL FORECAST IS A BLEND OF GFS AND ECMWF WITH MODERATE TO
FRESH CYCLONIC FLOW IN A BROAD SWATH AROUND THE LOW...ALTHOUGH
FAVORING THE STRONGER GFS SHOWING N WINDS TO 25 KT BY FRI
AFTERNOON OFF THE COAST OF VERACRUZ AHEAD OF THE ADVANCING LOW
PRES. MODEL CONSENSUS HOLDS THE PRES TO 1007 MB BY LATE FRI.
EXPECT PERSISTENT CONVECTION ACROSS THE SOUTHERN GULF BY THU AND
FRI AS THE LOW MOVES INTO THE AREA.

CARIBBEAN SEA AND TROPICAL N ATLC W OF 55W...
1008 MB LOW PRES IS CENTERED NEAR 15N82W...HAVING MOVED NNW FROM
ITS POSITION OF THE N COAST OF PANAMA YESTERDAY. THE LOW IS JUST
OFF THE COAST NEAR THE NICARAGUA/HONDURAS BORDER AND APPEARS TO
BE STAYING OVER THE WATERS AS OPPOSED MAKING AN EARLY LANDFALL
FURTHER WEST. THIS IS ALLOWING THE LOW TO STAY INTACT AND DEEPEN
SLIGHTLY. HOWEVER...AN UPPER LOW IS PARKED OVER THE S CENTRAL
GULF OF MEXICO AND IS DELIVERING WESTERLY SHEAR ACROSS THE
SURFACE LOW. STRONG CONVECTION FLARING CURRENTLY SOUTH OF
JAMAICA...IS DISPLACED TOO FAR EAST TO ASSIST THE DEVELOPMENT OF
THE LOW. GLOBAL MODEL CONSENSUS INDICATES THE LOW WILL TRACK MORE
WNW AND HUG THE HONDURAN COAST THROUGH TUE...IN RESPONSE TO ATLC
RIDGING BUILD WEST TOWARD THE CARIBBEAN...BEFORE CROSSING THE
TERRAIN OVER BELIZE...NORTHERN GUATEMALA AND SOUTHERN YUCATAN WED.
THE UPPER SHEAR BACKS MORE TO THE SW AND DIMINISHES SOMEWHAT AS
THE UPPER LOW DRIFTS WEST THROUGH WED. HOWEVER THE MODEST SHEAR
ALONG WITH TERRAIN EFFECTS WILL KEEP THE LOW FROM DEEPENING
APPRECIABLY THROUGH WED. EXPECT CONTINUAL CONVECTION OVER THE NW
CARIBBEAN INTO THU AS THE THE LOW AND ITS ACCOMPANYING SURFACE
TROUGH MIGRATE TO THE NW

[srainhoutx]

Morning e-mail from Jeff:

Interesting several days ahead as the tropics help to provide a good coverage of rainfall for the area.



Today-Wednesday:

Easterly wave is moving westward toward the upper TX coast this morning with the axis of this wave near the coast at sunrise. Numerous showers and thunderstorms are in progress on the eastern side of the wave axis from roughly Liberty and Chambers Counties eastward into central LA. Air mass will continue to moisten today as the wave axis moves westward allowing deep tropical moisture to move into the area from the ESE. PWS will rise to 1.7 inches this afternoon and over 2.0 inches on Tuesday. Expect widespread showers and thunderstorms today east of a lien from Conroe to Sugar Land to Bay City once upper 80 degree trigger temperatures are reached. With the wave axis further west on Tuesday and very deep moisture in place, expect numerous storms to develop prior to sunrise over the coastal waters and then move inland around sunrise. Saturated air column will support very heavy rainfall in a short period of time with a very quick 1-2 inches likely under the stronger storms. Wednesday should see a repeat of Tuesday with widespread morning development pushing inland through the day.



Thursday-weekend:

All attention will focus on the possible formation of some sort of tropical system in the southern Gulf of Mexico. Models are not in really any better agreement than last week on if/when/where this system may attempt to form and in what direction it may move. Central America monsoon trough has indeed lifted northward into the Caribbean Sea and extreme southern Gulf of Mexico and widespread convection is in progress over much of the Caribbean Sea this morning…very much as these models had been suggesting all last week. GFS and ECMWF have been the most consistent in developing a broad surface circulation in the southern Gulf or NW Caribbean Sea Thursday of this week and pushing it slowly WNW to NW into the western or northwestern Gulf this weekend. The latest CMC takes a NW Caribbean Sea NE toward FL as a strong tropical storm and this is being discounted as an outlier. Will lean toward the GFS/ECMWF solutions and trend in the direction of a broad (messy) surface low developing in the southern Gulf of Mexico this Thursday or Friday and meandering toward the WNW over the weekend. Will keep the system weak as the latest GFS has really broad low pressure extending over much of the central Gulf of Mexico. Confidence is low on both the development and any movement of a southern Gulf tropical system…stay tuned!



As far as any impacts go, tides are already running above normal along the TX coast due to easterly winds and tides are expected to come up even more as the ESE fetch increases off the Gulf early this week behind the westward moving easterly wave. Tides area currently running .5-1.0 feet above predicted levels at Galveston, Freeport, and Port O Connor. Toward the end of the week, as low pressure develops to the south, expect increasing fetch and seas again aimed at the TX coast so higher tides will likely linger into next weekend. Will just have to wait and see how much high pressure builds into the central US and how this may affect the moisture profile on the northern flank of any tropical system. Latest models have come in drier with more high pressure over the region this weekend. There could be a very strong rainfall gradient across the area with bands of heavy rains moving into the southern TX and possibly the coastal bend while areas further up the coast remain dry. As noted this is a low confidence forecast and significant changes are likely later this week if/when a surface circulation actually develops.



Now is a good time to remind residents to review their hurricane preparation plans and make sure their supply kits are fully stocked.

[jasons2k]

So what's up with this ridge? I heard nothing of it until yesterday afternoon's AFD. Then, on the news last night (CH 13), they say "all the models show a massive high pressure ridge next weekend and will shove anything in the Gulf south of us and keep us hot and dry".

Why the sudden 180? This really was out of left field for me. All we heard for weeks was 'monsoonal moisture coming' and then after one set of model runs - poof!

[srainhoutx]

So what's up with this ridge? I heard nothing of it until yesterday afternoon's AFD. Then, on the news last night (CH 13), they say "all the models show a massive high pressure ridge next weekend and will shove anything in the Gulf south of us and keep us hot and dry".

Why the sudden 180? This really was out of left field for me. All we heard for weeks was 'monsoonal moisture coming' and then after one set of model runs - poof!

A bit too much model hugging if you ask me. We appear to be on the Southern periphery of the heat ridge that guidance has suggested building across the Central Plains into the East Coast for many days. That to me would suggest more prevalent easterly wave activity beneath the ‘ring of fire’ along the Central/Western Gulf. The good news is we are not seeing this ridge established over N Mexico where we did last summer when an ever present NW flow aloft left us cloud free and brutally hot, even for Texas standards.

[Portastorm]

So what's up with this ridge? I heard nothing of it until yesterday afternoon's AFD. Then, on the news last night (CH 13), they say "all the models show a massive high pressure ridge next weekend and will shove anything in the Gulf south of us and keep us hot and dry".

Why the sudden 180? This really was out of left field for me. All we heard for weeks was 'monsoonal moisture coming' and then after one set of model runs - poof!

I dunno Jason ... in my uneducated opinion, I'm thinking it is nothing more than a numerical guess on the part of models and the strength of the high pressure. We're talking about five days away. Just like in the winter time when the models prog the strength and track of upper level lows and folks get all worked up one way or another ... I think this is similar. We probably won't know the strength/scope of the high pressure until later this week. I suspect the forecast is a low confidence one anyhow for next weekend. As srainhoutx says, "we shall see."

[Rip76]

Is it my eyes, or does it seem like all the convection in the gulf is losing it's punch as it rolls in?

[gocuse22]

I think rain chances should be bumped to 60 percent east of 45...50 west of 45

[Rip76]

Yes... Looking out my window (East Beltway & I-10) towards the gulf, I'm seeing some freaking towers out there.

[srainhoutx]

Is it my eyes, or does it seem like all the convection in the gulf is losing it's punch as it rolls in?

The trough axis is still to our E over the Lake Charles area. Our chances increase later this afternoon/tonight as we get that trough W of us and into those 2.0+ PW's offshore of Louisiana. Also of note, an upper low (almost TUTT like) is spinning near or just N of the Yucatan Channel along the southern edge of the trough axis. That will help pull additional moisture N into the Gulf from the Caribbean where shear is not conducive for any development. The Western Gulf still appears to be the area where more hospitable upper air conditions will reside during the late week time frame. We will see.

[Rip76]

For what it's worth, Joe Bastardi's twitter page.

http://twitter.com/BigJoeBastardi/statu ... 24/photo/1

[jasons2k]

That sorta flies in the face of the "death ridge", doesn't it?

[Rip76]

Ha, yes it sure does.

Maybe he's thinking of a slower developing storm?

[srainhoutx]

The 15Z surface analysis charts suggest a 1008mb surface low has formed just E of Belize City in the extreme NW Caribbean. That feature along with a tropical wave axis should slowly progress NW into the Bay of Campeche during the next couple of days.

[MontgomeryCoWx]

It's funny following Bastardi. I agree with him on a lot of things, but he's certainly not afraid to talk crap about the AGW folks. Lord, that man can get riled up.

FWIW, I agree with him about Dr. Mann.

[jasons2k]

but he has blown some shorter term forecasts, like Cat 3 Hurricane Rita coming right up the Houston Ship Channel....

Hehe - more like a solid 4 or 5 with Cat 3 winds all the way to Conroe. I'll never forget reading that post.

It was a better call than Tolleris though; he called Steve Lyons a "bald headed nut" for saying it was coming to Texas instead of Mexico. Fun times...

[srainhoutx]

The 12Z GFS suggests a broad unorganized area of low pressure crawling NW from the Western Caribbean with multiple areas of vorticity often seen within a monsoonal trough gyre. The general track would be N and W toward the NE Mexico/Lower/Middle Texas Gulf Coast early next week. There is a hint of a 'cool front' sagging S into the Tennessee Valley that is stretching a lot of moisture N and E into Florida. Also of note via the GFS is a bit of another easterly wave crossing the Northern Gulf later this week into the weekend heading generally W.