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

[KatDaddy]

Radar is lighting up quickly across the western portions of SE TX. The weather event is now underway. This will be a good two days of storm tracking and watching!

[jasons2k]

Yep - there are a lot of storms firing out ahead of the watch and the main area of activity. Would not be surprised to see another MCD or another watch posted east of the existing watch pretty soon.

[Ed Mahmoud]

If the perpetual soup, a product of Gulf and BoC air moving over cold Texas shelf waters breaks up and allows about 10ºF of warming today, much of Texas and Louisiana could see an interesting day.






The CRP sounding features an impressive 9º C/km mid-level lapse rate, so even with no surface heating, elevated t-storms could be impressive.

[Shoshana]

We're getting some pretty heavy rain now in NE Austin. Some lightning and thunder. Severe Thunderstorm Watch right now but no warnings for us right now.

Our power was out for half an hour this morning - something about a streetlight catching on fire. Bizarre.

[KatDaddy]

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 160
NWS STORM PREDICTION CENTER NORMAN OK
1025 AM CDT FRI APR 17 2009

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

SOUTHEAST TEXAS
COASTAL WATERS

EFFECTIVE THIS FRIDAY MORNING AND AFTERNOON FROM 1025 AM UNTIL
500 PM CDT.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 75 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 55 MILES SOUTH SOUTHEAST OF
PORT ARTHUR TEXAS TO 50 MILES SOUTH SOUTHWEST OF COLLEGE STATION
TEXAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED
WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

OTHER WATCH INFORMATION...CONTINUE...WW 159...

DISCUSSION...MCS CURRENTLY OVER SCNTRL TEXAS WILL CONTINUE EWD ALONG
A GRADIENT OF MODERATE INSTABILITY. A 45 TO 55 KT LOW-LEVEL JET WILL
CREATE A LOW-LEVEL SHEAR ENVIRONMENT FAVORABLE FOR A FEW TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 24020.


...BROYLES/HART

Hazard Tornadoes EF2+ Tornadoes
Likelihood Moderate Low
Severe Wind 65 kt+ Wind
Moderate Moderate
Severe Hail 2"+ Hail
Moderate Moderate

[KatDaddy]

SEVERE THUNDERSTORM WARNING
TXC015-089-171615-
/O.NEW.KHGX.SV.W.0051.090417T1525Z-090417T1615Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1025 AM CDT FRI APR 17 2009

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
NORTHWESTERN AUSTIN COUNTY IN SOUTHEAST TEXAS...
NORTHWESTERN COLORADO COUNTY IN SOUTHEAST TEXAS...

* UNTIL 1115 AM CDT

* AT 1022 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL. THIS
STORM WAS LOCATED NEAR WEIMAR...OR 6 MILES EAST OF SCHULENBURG...
AND MOVING NORTHEAST AT 25 MPH.

* LOCATIONS IN THE SEVERE THUNDERSTORM WARNING INCLUDE BUT ARE NOT
LIMITED TO COLUMBUS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM MAY PRODUCE LARGE DAMAGING HAIL...RESULTING IN EXTENSIVE
PROPERTY DAMAGE OR SERIOUS INJURY. AVOID WINDOWS AND TAKE COVER NOW!

&&

PLEASE REPORT SEVERE WEATHER TO THE COUNTY SHERIFF...LOCAL POLICE...
OR DEPARTMENT OF PUBLIC SAFETY AND ASK THEM TO RELAY YOUR REPORT TO
THE NATIONAL WEATHER SERVICE.

LAT...LON 2996 9659 3005 9663 3007 9659 3004 9650
2983 9642 2951 9674 2957 9679 2957 9682
2960 9686 2964 9688
TIME...MOT...LOC 1524Z 211DEG 20KT 2971 9680

[jasons2k]

X2

I must have ESP.

Seriously though - that leading edge looks pretty nasty.

[srainhoutx]

Update from HGX...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1043 AM CDT FRI APR 17 2009

.DISCUSSION...
TORNADO WATCH 160 HAS BEEN ISSUED FOR ALMOST ALL OF SOUTHEAST TEXAS...THE
BAYS AND THE NEARSHORE WATERS UNTIL 5 PM THIS AFTERNOON. CONDITIONS
ARE BECOMING INCREASINGLY FAVORABLE FOR SEVERE THUNDERSTORM DEVELOPMENT
THIS MORNING AND THIS AFTERNOON AS ACTIVITY CONTINUES TO DEVELOP AHEAD
OF THE EASTWARD MOVING CENTRAL/NORTH TEXAS MCS. HEAVY RAINFALL IS ALSO
BECOMING AN INCREASING THREAT. AN URBAN AND SMALL STREAM FLOOD ADVISORY
HAS ALREADY BEEN ISSUED FOR THE CURRENT ACTIVITY OUT WEST...AND IT IS
POSSIBLE THAT UPGRADES TO WARNINGS MIGHT BE NEEDED IF SOME SERIOUS TRAINING
PERSISTS. 42

[TexasSam]

FLOOD ADVISORY
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1036 AM CDT FRI APR 17 2009

TXC015-051-089-477-171730-
/O.NEW.KHGX.FA.Y.0004.090417T1536Z-090417T1730Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WASHINGTON TX-AUSTIN TX-COLORADO TX-BURLESON TX-
1036 AM CDT FRI APR 17 2009

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED AN

* URBAN AND SMALL STREAM FLOOD ADVISORY FOR...
NORTHWESTERN AUSTIN COUNTY IN SOUTHEAST TEXAS...
BURLESON COUNTY IN SOUTHEAST TEXAS...
WESTERN COLORADO COUNTY IN SOUTHEAST TEXAS...
WASHINGTON COUNTY IN SOUTHEAST TEXAS...

* UNTIL 1230 PM CDT

* AT 1033 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
VERY HEAVY RAIN WAS FALLING NEAR WEIMAR.

THUNDERSTORMS PRODUCING VERY HEAVY RAINFALL ARE MOVING THROUGH THE
ADVISORY AREA. ONE TO TWO INCHES OF RAIN HAVE ALREADY FALLEN ACROSS
PORTIONS OF COLORADO COUNTY AND MORE RAIN IS EXPECTED AS THESE
STORMS MOVE THROUGH. ADDITIONAL ACCUMULATIONS OF ONE TO TWO INCHES
ARE POSSIBLE OVER THE NEXT SEVERAL HOURS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL MAY CAUSE ELEVATED LEVELS ON
SMALL CREEKS...STREAMS...AND BAYOUS. ADDITIONALLY...PONDING OF WATER
WILL OCCUR ON FARM-TO-MARKET OR OTHER SECONDARY ROADS.

[jasons2k]

Shot at 2009-04-17

[srainhoutx]

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1058 AM CDT FRI APR 17 2009

TXC015-089-171615-
/O.CON.KHGX.SV.W.0051.000000T0000Z-090417T1615Z/
AUSTIN TX-COLORADO TX-
1058 AM CDT FRI APR 17 2009

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 AM CDT
FOR COLORADO AND AUSTIN COUNTIES...

AT 1056 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING LARGE DAMAGING HAIL UP TO
GOLF BALL SIZE. THIS STORM WAS LOCATED 6 MILES SOUTH OF WEIMAR...OR
9 MILES SOUTHEAST OF SCHULENBURG...AND MOVING NORTHEAST AT 25 MPH.

* LOCATIONS IN THE THE SEVERE THUNDERSTORM WARNING INCLUDE BUT ARE
NOT LIMITED TO WEIMAR...FRELSBURG AND COLUMBUS

[Flyinman]

Looks like I am going to have fun driving from The Woodlands to Beaumont and back this afternoon. Good thing I have my GPS to track the storms!

[srainhoutx]

...FLOOD WATCH IN EFFECT UNTIL 5 PM CDT THIS AFTERNOON...

THE NATIONAL WEATHER SERVICE IN HOUSTON/GALVESTON HAS ISSUED A

* FLOOD WATCH FOR A PORTION OF SOUTHEAST TEXAS...INCLUDING THE
FOLLOWING COUNTIES...AUSTIN...BRAZOS...BURLESON...COLORADO...
GRIMES...HOUSTON...MADISON...MONTGOMERY...TRINITY...WALKER...
WALLER AND WASHINGTON.

* UNTIL 5 PM CDT THIS AFTERNOON

*SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ACROSS THE WESTERN
PORTIONS OF SOUTHEAST TEXAS...ROUGHLY ALONG AND WEST OF A LINE
FROM MADISONVILLE TO PRAIRIE VIEW TO ROCK ISLAND. ACTIVITY
CONTINUES TO DEVELOP AND TRAIN TO THE NORTH ACROSS THE SAME
LOCATIONS THAT HAVE ALREADY RECEIVED 1 TO 3 INCHES OF RAIN.
THROUGH THIS AFTERNOON...ADDITIONAL RAINFALL TOTALS OF 2 TO 4
INCHES WITH ISOLATED 5 TO 7 INCH AMOUNTS COULD LEAD TO A SERIOUS
THREAT OF FLASH FLOODING.

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1106 AM CDT FRI APR 17 2009

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
WESTERN COLORADO COUNTY IN SOUTHEAST TEXAS...

* UNTIL 100 PM CDT

* AT 1104 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THAT FLASH FLOODING WAS LIKELY FROM A THUNDERSTORM NEAR WEIMAR.

* LOCATIONS IN THE FLOOD WARNING INCLUDE BUT ARE NOT LIMITED TO
SHERIDAN...ROCK ISLAND...FRELSBURG AND COLUMBUS.



BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1112 AM CDT FRI APR 17 2009

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
AUSTIN COUNTY IN SOUTHEAST TEXAS...
COLORADO COUNTY IN SOUTHEAST TEXAS...

* UNTIL NOON CDT

* AT 1108 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING LARGE DAMAGING HAIL UP TO
GOLF BALL SIZE. THIS STORM WAS LOCATED NEAR WEIMAR...OR 8 MILES
WEST OF COLUMBUS...AND MOVING NORTHEAST AT 20 MPH.

* LOCATIONS IN THE SEVERE THUNDERSTORM WARNING INCLUDE BUT ARE NOT
LIMITED TO SHELBY...NEW ULM...INDUSTRY...WEIMAR...COLUMBUS...FRELSBURG
AND CAT SPRING..

[srainhoutx]

Looks as if Fayette and Colorado Counties are getting some significant flooding.

[southerngale]

I'll wave as you pass through, Flyinman. Have a safe trip!

A tornado watch issued for today, and tomorrow is the day SPC has put us in a slight risk for severe storms. Oh boy... a lot to watch. I'm thinking our 1pm baseball game tomorrow might not happen.

Ed, or anyone else, can you explain how to read those CRP images? At least, the gist of it. I am pretty good at reading model maps, but I look at those and I might as well be looking at a corned beef sandwich. I doubt I'm alone. A little explanation on what to look for, etc. would be much appreciated.

*off to read Jeff Lindner's update above*

[JessRomero]

I was really really hoping this storm would like disappear lol My son's birthday party is tomorrow...... 2-4 great huh.... Well let's hope it dies down some how...

[srainhoutx]

Update from HGX...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1130 AM CDT FRI APR 17 2009

.DISCUSSION...
A FLOOD WATCH HAS BEEN ISSUED FOR WESTERN COUNTIES OF SOUTHEAST TEXAS.
HAVE BEGUN TO RECEIVE SOME REPORTS OF FLOODING DEVELOPING IN COLORADO
COUNTY WHERE THE HEAVIEST RAINFALL HAS BEEN INDICATED. EVERYTHING IS
MOVING RATHER SLOWLY TO THE EAST WHICH IS INCREASING THE THREAT OF
FLOODING. THE WATCH IS IN EFFECT UNTIL 5 PM. 42

[vbhoutex]

Looks as if Fayette and Colorado Counties are getting some significant flooding.

It is being mentioned on the local newscasts now.
Currently thundering without any rain yet in my area of Houston, but the radar looks ominous. Definitely starting to build SW too so it appears that almost all of Houston metro is in for a pounding this afternoon. Hail has been reported in the storms to our West. Definitely going to be watching and tracking.

[jasons2k]

Hi Southenrgale,

CRP = Corpus Christi - that's where the sounding took place.

Here are some tutorials that explain it better than I ever could --

High-level:

http://s214580749.websitehome.co.uk/tut ... ds-01.html

http://weather.unisys.com/upper_air/skew/details.html

More complicated:

http://www.eos.ubc.ca/courses/atsc201/A ... dings.html

[Ed Mahmoud]

Re: CRP - even with a noticeable warm nose about 750 mb, the reading is very unstable, which temperatures falling off quickly in the mid levels, for low level CAPE near 3000 J/Kg at 7 am CDT.


The really groovy thing, is while the integrated area dashed purple line and the red line is basically the CAPE, and could be calculated by met students/grads, they fill in the good stuff in text. I can see the CAPE, and the various lapse rates, the Lifted Index, Total Totals, Sweat Index (at least on model forecast skew-Ts) and the such, convective inhibition, helicity, and deep shear.

The picture just lets you look to see how much instability there is at low levels, and whether there is a warm nose capping surface parcels.


Hearing thunder now at the Galleria, sounds distant, time to check the radar...



Ahh, as I typed, someone linked to tutorials. Bravo!