SE TX/SW LA Discussion Thread - Heavy Rainfall Threat

[jasons2k]

Yep, I sure am. It's good that summer is pretty much here now. Pour me one of those

[jasons2k]

MESOSCALE DISCUSSION 0769
NWS STORM PREDICTION CENTER NORMAN OK
0256 PM CDT THU MAY 10 2007

AREAS AFFECTED...S CNTRL THROUGH SERN TX

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 101956Z - 102200Z

STORMS ARE EXPECTED TO DEVELOP ACROSS S CNTRL AND SERN TX AND MOVE
SEWD INTO THE EVENING. PRIMARY THREATS WILL BE ISOLATED LARGE HAIL
AND DAMAGING WIND GUSTS. CONVECTIVE TRENDS WILL CONTINUE TO BE
MONITORED.

A WELL DEFINED OCCLUDED UPPER LOW WAS LOCATED OVER CNTRL TX. VORT
MAX ALONG THE SWRN PERIPHERY OF THIS FEATURE WAS LOCATED JUST EAST
OF SAN ANGELO MOVING SEWD. THE SURFACE PATTERN IS RATHER WEAK.
HOWEVER...NUMEROUS BOUNDARIES EXIST INCLUDING ONE THAT EXTENDS FROM
CNTRL TX SWWD THROUGH S CNTRL TX NEAR HONDO. STRONG SURFACE HEATING
IS OCCURRING S OF THIS BOUNDARY WITH TEMPERATURES WARMING INTO THE
80S...BUT MID LEVEL LAPSE RATES ARE MODEST IN THIS REGION WITH 6.5
C/KM IN THE 700-500 MB LAYER ALONG WITH MLCAPE AROUND 1000 J/KG.
LAPSE RATES ARE STEEPER CLOSER TO THE UPPER LOW CENTER WHERE COLDER
AIR ALOFT EXISTS. FLOW THROUGH THE LOWEST 3 KM IS RATHER WEAK...BUT
A BAND OF 40 KT WLY TO NWLY 500 MB WINDS EXIST ON THE SRN PERIPHERY
OF THE UPPER LOW ACROSS S CNTRL AND S TX. THIS IS CONTRIBUTING TO
0-6 KM SHEAR OF 35 TO 40 KT WHICH IS SUFFICIENT FOR SOME STORMS TO
DEVELOP MID LEVEL ROTATION. STORMS ARE EXPECTED TO DEVELOP ALONG
SEWD MOVING CONVERGENCE BOUNDARY WITHIN REGION OF ASCENT ASSOCIATED
WITH SEWD ADVANCING VORT MAX ACROSS S CNTRL TX. MOST STORMS WILL
PROBABLY REMAIN MULTICELL IN CHARACTER...BUT SOME SUPERCELL
STRUCTURES WILL ALSO BE POSSIBLE.

[Stratosphere747]

Jeff just sent an email out mentioning the possibility of a severe thunderstorm watch for parts of the area. A bit unexpected.

Sure does "look" quiet out there.

[JenBayles]

Take a look at the radar now. Storms starting to pop.

[Stratosphere747]

We now have a severe thunderstorm watch for the area till 11 tonight.

http://www.spc.noaa.gov/products/watch/

http://www.spc.noaa.gov/products/watch/ww0266.html

[jasons2k]

It's sprinkling here now - yep radar is really lighting up esp. to our NW

[Stratosphere747]

Jason,

If you get a chance, could you throw an image up of the storm in Gonzales county? It briefly showed 70/75k ft cloud tops.

[KatDaddy]

I think it may be a rough evening with the rapid development of storms along the boundary stated in the Severe Thunderstorm Watch discussion. Upper low spinnng away across Central TX.

[JenBayles]

Severe Thunderstorm WatchSEVERE THUNDERSTORM WATCH OUTLINE UPDATE FOR WS 266
NWS STORM PREDICTION CENTER NORMAN OK
555 PM CDT THU MAY 10 2007

SEVERE THUNDERSTORM WATCH 266 IS IN EFFECT UNTIL 1100 PM CDT
FOR THE FOLLOWING LOCATIONS

TXC007-013-015-025-039-057-089-123-149-157-163-167-175-177-201-
239-255-273-283-285-297-311-321-339-355-391-409-469-473-481-493-
110400-
/O.NEW.KWNS.SV.A.0266.070510T2255Z-070511T0400Z/

TX
. TEXAS COUNTIES INCLUDED ARE

ARANSAS ATASCOSA AUSTIN
BEE BRAZORIA CALHOUN
COLORADO DEWITT FAYETTE
FORT BEND FRIO GALVESTON
GOLIAD GONZALES HARRIS
JACKSON KARNES KLEBERG
LAVACA LA SALLE LIVE OAK
MATAGORDA MCMULLEN MONTGOMERY
NUECES REFUGIO SAN PATRICIO
VICTORIA WALLER WHARTON
WILSON
$$




--------------------------------------------------------------------------------


Hazardous Weather Outlook
HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
629 PM CDT THU MAY 10 2007

TXZ163-164-176>179-195>200-210>214-226-227-235>238-111015-
AUSTIN-BRAZORIA-BRAZOS-BURLESON-CHAMBERS-COLORADO-FORT BEND-
GALVESTON-GRIMES-HARRIS-HOUSTON-JACKSON-LIBERTY-MADISON-MATAGORDA-
MONTGOMERY-POLK-SAN JACINTO-TRINITY-WALKER-WALLER-WASHINGTON-
WHARTON-
629 PM CDT THU MAY 10 2007

...SLIGHT RISK OF SEVERE WEATHER FOR WESTERN AND SOUTHERN PORTIONS
OF SOUTHEAST TEXAS THIS EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

.DAY ONE...TONIGHT

A SLIGHT RISK OF SEVERE THUNDERSTORMS REMAINS POSSIBLE FOR THE
WESTERN AND SOUTHERN PARTS OF SOUTHEAST TEXAS TONIGHT.
LOW LEVEL MOISTURE CONTINUES TO RETURN TO THE AREA...AS THE
ATMOSPHERE CONTINUES TO DESTABILIZE AS COLD AIR ALOFT ASSOCIATED
WITH AN UPPER LEVEL DISTURBANCE MOVES OVER WARM MOIST AIR NEAR THE
SURFACE. STRONG LIFT ASSOCIATED WITH THE DISTURBANCE WILL HELP
INITIATE THUNDERSTORM ACTIVITY MAINLY THIS EVENING INTO EARLY
FRIDAY MORNING. THE MAIN THREATS WILL BE DAMAGING DOWNBURST WINDS
AND HAIL WITH THESE STORMS. LOCALLY HEAVY RAINFALL MAY BE ANOTHER
THREAT AS STORMS ARE STILL EXPECTED TO MOVE SLOWLY ACROSS THE
AREA. THIS MAY CONTRIBUTE TO LOCALIZED FLASH FLOODING IN AREAS
WHERE GROUNDS ARE ALREADY SATURATED.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

HAZARDOUS WEATHER IS NOT EXPECTED.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL BE NEEDED TONIGHT.

[KatDaddy]

Thanks for the good news Jen

[JenBayles]

Any time KD! LOL!

[Extremeweatherguy]

Storms to the west are getting closer and closer and I have a feeling things are going to be exploding over Harris county within the next hour or two. The sky outside and the radar just look very ominous.

http://www.weatherunderground.com/radar ... rainsnow=0

[srainhoutx]

interesting to note seabreeze boundry via Radar Loop from HOU/GAL. Storms are firing in Harris County SWRD along that boundry...


http://radar.weather.gov/radar.php?rid= ... 1&loop=yes

[jasons2k]

Storms are exploding in across Harris & Montgomery Counties!

[jasons2k]

SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
707 PM CDT THU MAY 10 2007

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
HARRIS COUNTY IN SOUTHEAST TEXAS

* UNTIL 745 PM CDT

* AT 705 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
A SEVERE THUNDERSTORM. THIS STORM WAS LOCATED 5 MILES SOUTH OF
JERSEY VILLAGE...MOVING EAST AT 15 MPH.

[jasons2k]

Before (5:10PM)


After (7:10PM)

[JenBayles]

Yankeegirl - where are you? Are you noticing that the Bear Creek Dome is untouched thus far? All kinds of thunder rolling around in the hood, but so far, the Dome holds...

[JenBayles]

That cluster just now moving into Waller county looks nastier than the storms in Harris County for which the Warning was issued. Nasty lookin radar!

[vbhoutex]

SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
707 PM CDT THU MAY 10 2007

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
HARRIS COUNTY IN SOUTHEAST TEXAS

* UNTIL 745 PM CDT

* AT 705 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
A SEVERE THUNDERSTORM. THIS STORM WAS LOCATED 5 MILES SOUTH OF
JERSEY VILLAGE...MOVING EAST AT 15 MPH.

I just reported this to NWS about 10 min. ago. I'm a skywarn spotter, I don't know if that prompted the issuance, but we had 3/4" hail almost covering the ground. It still hasn't all melted and gone away. I got some pictures and will try to upload them in a little while.

[JenBayles]

They just issued a Severe Storm Warning for the cells in Waller county...