SE TX/SW LA weather: Much cooler and WET after Tuesday

[Ptarmigan]

I notice at Weather Underground, the low pressure is near us. How come no rain?

[srainhoutx]

HGX paints an interesting picture concerning the next several days and into the weekend. What catches my eye is newly declared 97E and how it may become involved in the weather across the area. Also looks as if we will finally see our first true Cold Front of the Fall Season as well...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
241 PM CDT MON SEP 14 2009

.DISCUSSION...
SCATTERED CONVECTION DEVELOPING ALONG AND AHEAD OF THE NORTH-SOUTH
ORIENTED WEAK SFC TROUGH WHICH IS NEAR THE I-45 CORRIDOR. THIS
ACTIVITY WILL PERSIST INTO THE EVENING HOURS WITH SOME ACTIVITY
LINGERING OVERNIGHT AS WELL. HAVE PLACED CHANCE POPS IN THE FCST
FOR THE NORTHEAST HALF OF THE AREA TONIGHT. UPPER LOW IS CENTERED
JUST NORTH OF THE CWA AND WILL PUSH SLOWLY EASTWARD THE NEXT
COUPLE OF DAYS. WEAK SFC LOW AND ASSOCIATED SFC TROUGH WILL SHIFT
EAST OF THE CWA ON TUESDAY. THE END RESULT WILL BE A GRADUAL
DRYING TREND AND INCREASE IN SUBSIDENCE ACROSS THE AREA. PWS WILL
REMAIN IN THE 1.7-1.9 INCH RANGE TUESDAY. GFS BUFR SOUNDINGS SHOW
THE ATMOSPHERE REMAINING UNCAPPED WITH CONVECTIVE TEMPS IN THE
LOWER 80S. BEST CONVECTIVE COVERAGE WILL BE OVER THE NE ZONES
CLOSER IN PROXIMITY TO THE UPPER LOW. WILL KEEP CHANCE POPS GOING
FOR THE NE HALF OF THE AREA TUESDAY. FLOW IN THE LOW TO MID LEVELS
BECOMES MORE NORTHWESTERLY BEGINNING TUESDAY NIGHT AND LASTING
THROUGH THE END OF THE WEEK RESULTING IN MORE DRYING/SUBSIDENCE.
PWS WILL GRADUALLY DECREASE...LOWERING TO THE 1.5-1.7 INCH RANGE
WEDNESDAY...1.4-1.6 INCHES THURSDAY...AND 1.2-1.4 INCHES FRIDAY.
WILL FCST 30 POPS ONLY IN THE FAR NORTHEAST WEDNESDAY WITH 20S
ELSEWHERE WEDNESDAY AND AREA WIDE THURSDAY. BY FRIDAY WILL CONFINE
20 POPS ONLY TO THE SOUTHERN HALF WHERE DEEPEST MOISTURE WILL BE
LOCATED. EVEN THE 20 POPS THURSDAY/FRIDAY MAY BE GENEROUS OVER
WRN ZONES. AS THE DRIER AIRMASS WORKS INTO SE TX...WILL SEE A
LOWERING OF SFC DEWPOINTS AND SLIGHTLY COOLER OVERNIGHT LOWS
BEGINNING WED NIGHT. MOST INLAND AREAS WILL BEGIN TO DROP INTO THE
60S. MEDIUM RANGE MODELS FORECAST YET ANOTHER UPPER TROUGH TO
DEVELOP OVER THE SRN ROCKIES LATE WEEK AND MOVE ACROSS THE SRN
PLAINS THIS WEEKEND. WILL SEE A GRADUAL INCREASE IN MOISTURE
LEVELS IN RESPONSE TO THIS FEATURE OVER THE WEEKEND...WITH PWS
BACK UP TO 1.5-1.7 INCHES BY SUNDAY. HAVE 20 POPS MOST AREAS FOR
SATURDAY/SUNDAY...BUT INTRODUCED CHANCE POPS SOUTH SUNDAY AFTN.
WITH SUNSHINE THE SRN ZONES WILL SEE TEMPS FLIRT WITH 90 THE NEXT
COUPLE OF DAYS BEFORE SETTLING BACK INTO THE MID/UPPER 80S LATE
WEEK/WEEKEND. LOOKING AHEAD...THE GFS AND ECMWF FORECAST A PATTERN
AMPLIFICATION AND WHAT LOOKS LIKE THE FIRST SIGNIFICANT COLD
FRONT OF THE SEASON TO CROSS SE TX AT SOME POINT IN THE 7 TO 10
DAY PERIOD. THE PATTERN CHANGE IS SUPPORTED BY THE GFS ENSEMBLE
MEAN AND IS THE CLIMATOLOGICALLY FAVORED TIME WHICH INCREASES
CONFIDENCE. SOMETHING TO WATCH IN THE COMING DAYS (NOT THAT
SOUTHEAST TEXAS RESIDENTS COULD POSSIBLY BE ANTICIPATING THIS OR
ANYTHING).
35

[somethingfunny]

Not that anybody's anticipating autumn.

[Tireman4]

Nahh, not that ANYONE is wanting cooler weather....

[SaskatchewanScreamer]

Now I'm really enjoying the warmth we are finally getting (we haven't had a hint of frost here yet)..........
Wed 82°F
Thurs 79°F
Fri 82°F
Sat 88°F

However I'll happily give Old Man Winter the directions to Texas (he can go through Alberta or Manitoba )


Everyone here has their fans facing due north ............

[jasons2k]

So, here are my storm totals:
.65"
.83"
.04"
.04"
.06"

= Total of 1.62"

Not as much as I thought I would get, but not a total bust either. 5 days of some measurable precip.

[vbhoutex]

My total for the 5 days was 0.42" and that could be stretching it, but I did have a 0.95" day like three days before we thought we were going to be deluged. Today's clouds and breeze make it ideal for working in the yard, especially since the ground isn't like concrete now. I have been taking advantage of that. Is it beer:30 yet?

[Nederlander]

I dont know about the rest of you.. but im ready for the 50s and 60s.. guess thats still another couple of months though

[srainhoutx]

Great weather after a summer of high electric bills. Looks like some cooler air is headed our way next week. I noticed that HGX is mentioning another shot at rain for the weekend before we see the cooler temps. EPAC 97E moisture along with another Upper Air feature looks hopeful for TX.

[Ptarmigan]

Great weather after a summer of high electric bills. Looks like some cooler air is headed our way next week. I noticed that HGX is mentioning another shot at rain for the weekend before we see the cooler temps. EPAC 97E moisture along with another Upper Air feature looks hopeful for TX.

Hope we get rain from that. Nice to see cooler weather.

[srainhoutx]

Morning e-mail from Jeff...

Pesky stacked low pressure system over SW Arkansas that has brought the wet weather to central and north TX the past several days is starting to retrograde back westward.

Forecast models have changed their tune on the system over AR and now instead of shifting it off to the E, bring it back into NE TX then S into E TX and then by Friday send it on eastward. WNW flow on the southwest side of this feature is resulting in a drier air mass advecting into SE TX. However, deep layered moisture with PWS upwards of 1.8 inches is not that far away to our NE and with the low pressure drifting W and then S, some of this moisture will wrap back into our NE counties starting this afternoon. After a review of the water vapor, the low clearly has all the activity focused on the N and NW sides of the system will little ongoing to the S of the feature. Unlike yesterday, skies are fairly clear over the region and this will allow temperatures to warm toward trigger levels this afternoon in the upper 80’s. Feel the best chances for showers will be NE of a line from College Station to Liberty.

Feature gets closer on Thursday and expect much more low and mid level cloud cover. This should hold down afternoon highs and keep any rainfall scattered at best. The upper low finally gets the boot on Friday, as yet another upper air system currently over the Rockies drops SE into the plains. Will see a rapid increase in tropical moisture over the weekend as offshore flow returns to onshore allowing moisture to surge northward and we may tap high level moisture from newly formed TD # 16 in the EPAC. Upper flow becomes increasingly diffluent by late Sunday into early next week while a decent looking cold front slides down the plains into TX. Chances for rains will be back on the upswing Sat-Tues as moisture returns and disturbances cross the area ahead of the frontal boundary.

[jasons2k]

Looks like areas around Beaumont are getting some more rain. And it's still from the same upper low as last week.

[funster]

Vertically stacked system from NWS Fort Worth discussion

THE LOW PRESSURE SYSTEM CONTINUES TO WANDER WESTWARD...BUT WILL
BEGIN TO DROP SOUTH TONIGHT AND TOMORROW. THIS LOW IS ESSENTIALLY
ACTING AS A REMNANT TROPICAL CYCLONE...WITHOUT THE FANFARE OF EVER
BEING A TROPICAL SYSTEM WITH A NAME. THE LOW IS VERTICALLY
STACKED...FORMED IN A LOW SHEAR ENVIRONMENT...AND HAS A WARM-
CORE...MEANING THICKNESS VALUES/TEMPERATURES IN THE CORE OR CENTER
OF THE LOW ARE WARMER THAN THE SURROUNDING ENVIRONMENT.

BECAUSE OF ITS WARM CORE DYNAMICS...LAPSE RATES ARE LOW AND
INSTABILITY BECOMES LIMITED WITHOUT AN ACCESS TO A SUSTAINED
SOURCE OF HIGH THETA-E AIR. THIS IS WHY TROPICAL CYCLONES REQUIRE
WARM OCEAN WATERS...BECAUSE IT SUPPLIES AN ENORMOUS SOURCE OF LOW
LEVEL INSTABILITY FOR CONTINUOUS DEEP CONVECTION. OUR CURRENT WARM
CORE LOW FORMED OVER LAND AND HAS WRAPPED STABLE CONTINENTAL AIR
ALL THE WAY AROUND THE CIRCULATION. THUS...THE INSTABILITY IS
WEAK...AND THUNDERSTORMS HAVE BEEN NEARLY NON-EXISTENT...WITH
SHALLOW CONVECTION DOMINATING. STILL...WITH JUST THIS MEAGER
BAROTROPIC INSTABILITY...WE HAVE A SURFACE LOW CENTER OF 1007
MB...A CURIOUS EFFECT OF PRESSURE FALLS AND STRONGER NORTH WINDS
TONIGHT...AND LASTLY A RADAR PRESENTATION SHOWING IMPRESSIVE
SPIRAL BANDING.

ALL IN ALL...THE FORECAST WILL BE UPDATED TO RAISE WINDS AND LOW
TEMPS A BIT. WILL KEEP THE CURRENT POP AND QPF CONFIGURATION
WITH BEST CHANCES OF RAIN IN THE EAST WITH AVERAGE QPF OF AN INCH
OR SO. ONE THING TO NOTE...IS THAT BECAUSE WE ARE ESSENTIALLY
DEALING WITH A REMNANT TROPICAL CYCLONE...THERE IS A POSSIBILITY
OF CORE RAINS TONIGHT NEAR THE CENTER. CONTEMPLATED A SMALL FLASH
FLOOD WATCH OVER THE EASTERN ZONES...BUT AGAIN...THE COMPLETE LACK
OF HIGH THETA-E AIR AVAILABLE TO THIS SYSTEM WILL INHIBIT DEEP
CONVECTION AND THUS THE POTENTIAL FOR FLASH FLOOD PROVOKING
RAINFALL.

[jasons2k]

Yeah, they note that on the HGX discussion as well.

Even though we'll have minimal impacts from this, we are right on the edge of what could have been some significant additional rains with this. It's a good lesson that we shouldn't declare something 'done and over' until it is completely gone.

[srainhoutx]

Lake Charles just updated and provides a great discussion of the feature, as well as the frontogenisis along the NW GOM. One can almost feel a touch of fall in the air.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAKE CHARLES LA
1000 AM CDT THU SEP 17 2009

.UPDATE...THE LOW PRESSURE SYSTEM HAS FINALLY BEGUN TO SPIN DOWN
AS EVIDENCED BY THE RISE IN CENTRAL PRESSURE TO 1008MB THIS
MORNING AND IS LOCATED NORTHWEST OF LUFKIN. THE PARTNER CUTOFF
HIGH WHICH HAD BEEN OVER THE DAKOTAS HAS RETROGRADED WEST TO THE
WYOMING SOUTH DAKOTA AREA. THIS WILL TEND TO DRAW OUR LOW FURTHER
TO THE WEST IN A SIMILAR RETROGRADE FASHION. IN TURN THIS WILL
ALLOW FOR MORE MOISTURE AS WE GAIN THE SOUTHEAST SECTOR.
INTERESTING FEATURES WITH THIS LOW PRESSURE SYSTEM ARE THE GENESIS
OF A WARMFRONTAL OCCLUSION AROUND THE SHREVEPORT AREA AND THE
FRONTOGENISIS OF A COLD FRONT WITH UPPER LEVEL H3 SUPPORT AND SEEN
ON VISIBLE IMAGERY FROM THE ATCHAFALAYA BASIN OUT OVER THE GULF TO BROWNSVILLE.
RADAR AND VISIBLE IMAGERY SHOWING WAVES ALREADY ON THIS FRONT
KICKING OFF THUNDERSTORM OVER THE GULF UPSTREAM OF OUR EASTERN WATERS.

ADJUSTED POPS UP FOR THOSE EASTERN WATERS TODAY AND LOWERED FOR
INTERIOR SE TX WHERE A DRY SLOT IS SHOWING UP. LOWERED TEMPS AS
MUCH AS 4 DEGREEES THIS AFTERNOON WITH THE EXPECTED SPREAD OF
CLOUD COVER IN THE INCREASINGLY MOIST AIR. UPDATED ZONES OUT
SHORTLY.

SWEENEY

Edit to add HGX Update as well...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1008 AM CDT THU SEP 17 2009

.UPDATE...
QUICK UPDATE TO LOWER TEMPS NORTH AND INCREASE CLOUD COVER.
&&

.DISCUSSION...
ABUNDANT MOISTURE EVIDENT ON SATELLITE AND WITH EXPANSIVE CLOUD
COVER SURROUNDING THE UPPER LOW HAVE GONE WITH CLOUDY SKIES OVER
THE NORTH FOR THE AFTERNOON HOURS. WITH THIS CLOUD COVER
TEMPERATURES SHOULD STRUGGLE UP THROUGH THE 70S IN THE NORTH AND
CUT BACK TEMPS 2-4 DEGREES IN THE NORTH. W OR WNW WINDS A BIT
STRONGER THAN PREV FORECAST SO HAVE NUDGED UP WINDS IN GRIDS AND
TAFS AND GIVEN THE LEDBETTER PROFILER THESE SHOULD CONTINUE WHERE
THE BETTER MIXING WILL GO ON SOUTH OF THE CLOUD BANK. RAIN
CHANCES STILL REASONABLE IN CLOSER PROXIMITY TO THE UPPER LOW NEAR
LFK BUT THE SPEED MAX PRESENT YESTERDAY IS WELL EAST AND WV AND
MODELS INDICATE A GOOD DEAL MORE SHEARING GOING ON SO DO NOT
ANTICIPATE MUCH OTHER THAN SHOWERS THROUGH 2 PM THEN POSSIBLY A
FEW THUNDERSTORMS MAINLY EAST THE I-45 CORRIDOR.

45

[srainhoutx]

HGX thoughts on upcoming Cold Front and new cutoff Upper Low for next week...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
354 AM CDT FRI SEP 18 2009

.DISCUSSION...
WRAP AROUND CLOUDINESS AGAIN OVER THE REGION THIS MORNING. LIKE
YDAY...WILL LIKELY HAVE A WIDE RANGE OF HIGH TEMPS DEPENDING ON WHO
SEES SOME SUNSHINE (SW/SRN PARTS OF THE CWA). SAT PIX SHOW THE
CUT-OFF LOW APPEARING TO BE TAKING AN EWD TREK AND OPENING UP AND
FILLING AS MODELS SUGGEST. SURFACE CIRCULATION LOOKS LIKE IT`LL
HANG TOGETHER IN LA FOR THE NEXT 36 HOURS OR SO. WEEKEND WX LOOKS
UNEVENTFUL. MID LEVEL FLOW BECOMES SW ALLOWING FOR A FEW IMPULSES TO
MOVE OVERHEAD...BUT NOT EXPECTING MUCH OTHER THAN PERIODS OF CLOUD
COVER. MUCH ADVERTISED FRONT STILL ON TARGET TO PUSH THRU SE TX ON
TUE AS H5 TROF/LOW DROPS INTO THE PLAINS. WILL BEGIN NUDGING POPS UP
JUST A BIT AHEAD OF FROPA WITH GOOD MODEL AGREEMENT. LOOKS LIKE THE
H5 LOW WILL PULL UP NEARLY STATIONARY IN THE SRN PLAINS DURING THE
2ND HALF OF THE WEEK AS RIDGE ANCHORED OVER THE SE STATES HOLDS
STRONG. THIS WOULD KEEP US IN A SW FLOW ALOFT & DEPENDING ON HOW FAR
SOUTH IT DOES STALL WE COULD BE SUSCEPTIBLE TO SOME OVERRUNNING
MOISTURE & IMPULSES EMBEDDED IN THE FLOW ALOFT. GFS KEEPS SOME
PRECIP ALONG AND JUST OFF THE COAST THRU THE END OF THE WEEK...WHILE
ECMWF AND CANADIAN LOOK TO KEEP IT WELL BEYOND 60NM OFFSHORE. WILL
MAINTAIN SOME LOWISH POPS CLOSER TO THE COAST AND ADJUST UP/DOWN AS
FCST CONFIDENCE IMPROVES. 47

[Diva]

It's so gloomy here this morning. Grey skies and lots of moisture in the air. But, hey, it's not hot!

[srainhoutx]

HPC dismissing the GFS for now...

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
403 AM EDT SAT SEP 19 2009

VALID 12Z WED SEP 23 2009 - 12Z SAT SEP 26 2009

THE MAIN FEATURE ACROSS THE CONUS THROUGH THE MEDIUM RANGE PERIOD
WILL BE A NEARLY STATIONARY CUT OFF CIRCULATION OVER THE PLAINS.
GENERALLY FOLLOWED THE 00Z ECMWF WITH SOME SUPPORT FROM THE CMC
WITH THE POSITION OF THIS SYSTEM. GIVEN THE MODEL TRENDS ON THE
00Z CYCLE...THE ASSOCD SFC BNDRYS OVER THE CENTER OF THE NATION
HAVE BEEN ADJUSTED TO THE WEST. THE GFS...WHICH RETROGRADES THE
CLOSED LOW INTO THE SWRN STATES...DOES NOT HAVE SUPPORT FROM OTHER
OPERATIONAL MODELS OR ENS MEAN GUIDANCE.

ELSEWHERE...BIG MODEL DIFFS ARE ALSO NOTED OVER THE NORTHEAST DAYS
5-6 WITH THE GFS AND ESPECIALLY THE ECMWF DEVELOPING A TROUGH
WHILE THE UKMET AND CMC KEEP A RIDGE OVER MUCH OF THE EAST. WITH
SUPPORT FROM THE GLOBAL ENS MEAN...LEANED TOWARD THE GFS/ECMWF
TROUGH WITH A COLD FRONT SLICING THROUGH THE REGION. 00Z
GUIDANCE IS IN BETTER AGREEMENT OVER THE NORTHWEST WHERE A STRONG
RIDGE SHOULD HOLD IN PLACE AS PAC SYSTEMS STAY MOSTLY NORTH OF THE
BORDER.

HEDGE

HGX will slow FROPA a bit and hold off until guidance becomes a bit clearer...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
336 AM CDT SAT SEP 19 2009

.DISCUSSION...
FAIRLY UNEVENTFUL WX EXPECTED THIS WEEKEND...JUST VARIABLE
MID/HIGH CLOUDINESS AND PERHAPS SOME ISOLATED SHRA/TSTMS AS WEAK
UPPER IMPULSES RIDE OVERHEAD IN THE WSW FLOW ALOFT. ONSHORE FLOW
RESUMES BY LATE SUNDAY AS PRESSURES FALL TO THE NW.

FCST BEYOND MONDAY STILL QUITE UNCERTAIN...EVEN MORE SO THAN THIS
TIME YDAY. MODELS DIG THE NEXT TROF & CUTOFF LOW INTO THE PLAINS
EARLY NEXT WEEK. THE 00Z GFS TAKES IT SWWD INTO NV ON WED...
WHEREAS ECMWF AND CANADIAN KEEP IT SOME 900 MILES EAST IN THE
OK/KS/TX PANHANDLE. EVENTUAL PLACEMENT WILL OBVIOUSLY HAVE
IMPORTANT RAMIFICATIONS REGARDING SE TX WX. IF GFS SOLN ENDS UP
BEING CORRECT...WE MAY NOT EVEN SEE MUCH IN THE WAY OF A FROPA OR
DRIER AIRMASS MOVE IN...WHILE THE REVERSE WOULD BE TRUE WITH THE
CANADIAN/ECMWF. SINCE GFS SEEMS TO BE THE CURRENT OUTLIER...AND
CANADIAN/ECMWF ARE MORE SIMILAR TO EARLIER MODEL CONSENSUS SOLNS
FEEL IT IS BEST TO HOLD TIGHT WITH THE ONGOING FCST AT THIS TIME
AND SEE WHAT THE NEXT COUPLE SUITE OF MODELS HAVE TO SAY BEFORE
MAKING ANY BIG CHANGES. WE DID SLOW THE FROPA DOWN ABOUT 6-12
HOURS...NOW LATE TUE AND ADJUSTED APPROPRIATE WX GRIDS...BUT THAT`S
ABOUT THE MOST SIGNIFICANT CHANGES MADE TO THE FCST IN THE
MEDIUM/LONG RANGE FOR THE TIME BEING. 47

[vbhoutex]

I just hope we do get FROPA and some rain since we didn't get much from the last system. I am not surprised at the changes, especially for this time of year.

[CajunMama]

The humidity is killing me already! I was just outside, just standing around and i'm drenched already. It's going to be a long day outside. Bre and her family along with my daughter and i are heading to baton rouge in a couple of hours for an afternoon of tailgating and an evening of cajun and tigger football.