April - Ends on Mild Note

[srainhoutx]

MESOSCALE DISCUSSION 0370
NWS STORM PREDICTION CENTER NORMAN OK
0159 PM CDT TUE APR 02 2013

AREAS AFFECTED...CNTRL TX

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 021859Z - 022000Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...TSTM COVERAGE SHOULD INCREASE THROUGH THE AFTERNOON ALONG
AND AHEAD OF A SWD MOVING COLD FRONT. AN ACCOMPANYING THREAT OF DMGG
WINDS AND LARGE HAIL MAY ALSO DEVELOP WITH THE STRONGEST
TSTMS...POSSIBLY REQUIRING ISSUANCE OF A WW.

DISCUSSION...POCKETS OF HEATING WITHIN BREAKS OF WIDESPREAD
CLOUDINESS HAVE ALLOWED TEMPERATURES TO APPROACH 80 F IN SOME
LOCATIONS...WITH AN INCREASE IN CONVECTION NOTED INVOF LOCALIZED
DIFFERENTIAL HEATING ZONE OVER LLANO COUNTY. THIS IS OCCURRING S OF
A SLOW-MOVING COLD FRONT...WHICH WAS ANALYZED FROM NEAR SJT-BWD-30 S
FTW AS OF 19Z. DESPITE THE PRESENCE OF CLOUD COVER LIMITING SFC
HEATING...MOIST BOUNDARY LAYER CONDITIONS /E.G. SFC DEWPOINTS LOWER
60S/ ALONG WITH INCREASING ASCENT ACCOMPANYING AN UPPER IMPULSE
APPROACHING THE BIG BEND REGION SHOULD PROMOTE A GENERAL INCREASE IN
CONVECTION ALONG AND AHEAD OF THE COLD FRONT. HIGH-RESOLUTION
GUIDANCE SUGGESTS CONVECTION SHOULD EVOLVE INTO A SEMI-ORGANIZED
FRONTAL CLUSTER OR LINE THIS AFTERNOON ACROSS CNTRL TX. A DMGG WIND
THREAT MAY ACCOMPANY THIS ACTIVITY...BUT COULD BE LIMITED BY
ANAFRONTAL CHARACTER OF THE REGIME. ADDITIONALLY...THE POTENTIAL FOR
HAIL AND LOCALIZED DMGG WINDS...AND PERHAPS A BRIEF TORNADO...COULD
ACCOMPANY PRE-FRONTAL DISCRETE STORMS THAT OCCUR. CONVECTIVE TRENDS
WILL CONTINUE TO BE MONITORED FOR SIGNS OF INCREASING COVERAGE AND
INTENSIFICATION WHICH MAY REQUIRE A WW.

..ROGERS/CORFIDI.. 04/02/2013


ATTN...WFO...HGX...FWD...EWX...SJT...

[Andrew]

Also keep an eye out west as the energy progresses west. Could be trouble later:

MESOSCALE DISCUSSION 0369
NWS STORM PREDICTION CENTER NORMAN OK
0142 PM CDT TUE APR 02 2013

AREAS AFFECTED...BIG BEND REGION OF SWRN TX INTO THE EDWARDS PLATEAU
AREA

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 021842Z - 022015Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...SEVERE THREAT IS EXPECTED TO INCREASE OVER THE NEXT 1-2
HOURS...WITH LARGE HAIL AND LOCALLY DAMAGING WINDS EXPECTED. WW
ISSUANCE MAY BECOME NECESSARY IN THE NEXT HOUR OR SO.

DISCUSSION...VISIBLE SATELLITE IMAGERY SHOWS A CLEAR TO PARTLY
CLOUDY SKY ACROSS WRN PORTIONS OF THE DISCUSSION AREA...W OF THE LOW
CLOUD DECK WHICH EXTENDS AS FAR WWD AS ROUGHLY VAL VERDE AND
CROCKETT COUNTIES. HERE...AFTERNOON HEATING COMBINED WITH UPPER 40S
TO NEAR 50 F SURFACE DEWPOINTS HAS YIELDED MODEST
DESTABILIZATION...RESULTING IN SCATTERED/WEAK CONVECTIVE DEVELOPMENT
PER VISIBLE SATELLITE AND LIGHTNING DATA. AS LARGE-SCALE ASCENT
CONTINUES TO INCREASE IN ADVANCE OF THE MAIN UPPER SYSTEM CROSSING
THE FOUR CORNERS AREA AND A SECONDARY FEATURE CROSSING NWRN
MEXICO...EXPECT A FURTHER INCREASE IN THUNDERSTORMS ACROSS THE BIG
BEND REGION.

WHILE LIMITED MOISTURE/INSTABILITY W OF THE LOW CLOUD SHIELD MAY
HINDER SEVERE POTENTIAL INITIALLY...MORE FAVORABLY MOIST/UNSTABLE
AIRMASS E OF THIS REGION SHOULD PERMIT STORMS TO INTENSIFY AS THEY
SHIFT EWD FROM THE INITIATION ZONE. THUS -- WITH POTENTIAL FOR
LARGE HAIL AND DAMAGING WINDS TO INCREASE WITH TIME...WW MAY BE
NEEDED.

..GOSS/CORFIDI.. 04/02/2013


ATTN...WFO...EWX...SJT...MAF...

LAT...LON 29610448 30120473 31110385 31510183 31399980 29849986
28730050 29620148 29710246 28910306 29280416 29610448

[Andrew]

SEL9

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 79
NWS STORM PREDICTION CENTER NORMAN OK
235 PM CDT TUE APR 2 2013

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

SOUTHERN AND CENTRAL TEXAS

EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 235 PM UNTIL
1100 PM CDT.

HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 185
STATUTE MILES EAST AND WEST OF A LINE FROM 75 MILES EAST
NORTHEAST OF SAN ANGELO TEXAS TO 5 MILES EAST OF DEL RIO TEXAS.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU9).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR 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. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

DISCUSSION...TSTMS EXPECTED TO INCREASE IN SEVERAL PARTS OF WW AREA
THROUGH THIS EVE: /1/ ALONG LEE TROUGH/DRY LINE NEAR THE DAVIS
MOUNTAINS AS MID-LVL COOLING ASCENT WITH NRN MEXICO/CHIHUAHUA UPR
IMPULSE AND SFC HEATING FURTHER DESTABILIZE REGION OF MOIST UPSLOPE
FLOW.../2/ ALONG AND N OF W-E COLD FRONT ADVANCING SLOWLY S THROUGH
THE SRN EDWARDS PLATEAU/HILL COUNTRY...AND /3/ ALONG WEAK NW/SE WARM
FRONT/DIFFERENTIAL HEATING BOUNDARY OVER THE ERN HILL COUNTRY INTO
THE WRN PORTIONS OF THE MIDDLE TX CSTL PLN.
MODERATE /25-35 KT/ WLY DEEP SHEAR AND SUSTAINED...SEASONABLY MOIST
LOW-LVL INFLOW SUGGEST GOOD POTENTIAL FOR A FEW SUPERCELLS WITH
LARGE HAIL/LOCALLY DMGG WIND. THIS ACTIVITY SHOULD MERGE INTO ONE OR
TWO SIZABLE MCSS BY MID EVE. A TORNADO OR TWO ALSO CANNOT BE RULED
OUT LATER THIS AFTN...BOTH IN THE BIG BEND REGION WHERE LOW-LVL
LAPSE RATES WILL BE MAXIMIZED UNDER PARTLY CLEAR SKIES...AND IN ERN
QUARTER OF WW...INVOF DIFFUSE WARM FRONT. ENVIRONMENT AND STORM
CHARACTER IN THESE AREAS WILL BE MONITORED FOR POSSIBLE WATCH
UPGRADES.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM
MOTION VECTOR 29025.


...CORFIDI

[srainhoutx]

A strong upper air disturbance/short wave currently South of the Big Bend in NE Mexico is approaching and severe storms are beginning to fire NW of Austin...

[srainhoutx]

Golfball sized hail reported near Spicewood/Marble Falls to the NW of Austin...

[srainhoutx]

Storms developing across Western areas of SE Texas. Areas near Fulshear, Brenham, Katy and NW Harris County will be affected before long.

[srainhoutx]

The Storm Prediction Center expands the Slight Risk for severe storms to include a bit more of SE Texas. Large hail and damaging wind gusts are the primary threat.

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0300 PM CDT TUE APR 02 2013

VALID 022000Z - 031200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM SWRN THROUGH CNTRL AND
SERN TX...

...SWRN THROUGH CNTRL AND SERN TX...

WARM SECTOR HAS BECOME MODERATELY UNSTABLE SOUTH OF A COLD FRONT
THAT EXTENDS FROM NERN TX SWWD THROUGH SWRN TX NEAR FORT STOCKTON
WHERE IT INTERSECTS A DRYLINE. STORMS ARE DEVELOPING ALONG THE SWD
ADVANCING FRONT ACROSS CNTRL AND SWRN TX AS WELL AS OVER THE
MOUNTAINS OF SWRN TX. VERTICAL SHEAR FROM 30-35 KT CHARACTERIZES
MOST OF THE WARM SECTOR WITH ELY NEAR SFC WINDS VEERING TO WLY WITH
HEIGHT. WV IMAGERY INDICATES WHAT APPEARS TO BE AN UPPER IMPULSE
MOVING INTO SWRN TX AHEAD OF THE MAIN UPPER LOW...AND SOME INCREASE
IN DEEP LAYER VERTICAL SHEAR MAY OCCUR DURING THE EVENING AS THIS
FEATURE CONTINUES EWD. THE ENVIRONMENT SHOULD BECOME INCREASINGLY
FAVORABLE FOR ORGANIZED STORMS INCLUDING POTENTIAL FOR ROTATING
UPDRAFTS AND LATER POSSIBLE BOWING SEGMENTS AS STORMS CONGEAL WHILE
DEVELOPING EWD. PRIMARY THREATS APPEAR TO BE LARGE HAIL AND DAMAGING
WIND WITH VERY LARGE HAIL POSSIBLE OVER PORTIONS OF SWRN INTO CNTRL
TX WHERE STEEPER LAPSE RATES AND STRONGER INSTABILITY EXIST. THOUGH
HODOGRAPHS ARE NOT PARTICULARLY LARGE...A COUPLE TORNADOES CANNOT BE
RULED OUT FROM SWRN TX INTO SCNTRL TX GIVEN SUFFICIENT
INSTABILITY...A MOIST BOUNDARY LAYER AND VEERING LOW LEVEL WINDS
WITH HEIGHT.

OTHER ELEVATED STORMS MAY DEVELOP LATER TONIGHT OVER WRN TX NORTH OF
THE FRONT AND POSE SOME RISK FOR HAIL.

..DIAL.. 04/02/2013

[srainhoutx]

Severe Thunderstorm Watch may be coming shortly for portions of SE Texas...

MESOSCALE DISCUSSION 0371
NWS STORM PREDICTION CENTER NORMAN OK
0338 PM CDT TUE APR 02 2013

AREAS AFFECTED...MIDDLE TX COASTAL PLAIN

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 022038Z - 022145Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...STORM COVERAGE IS INCREASING WITHIN A WARM ADVECTION
REGIME ACROSS THE MIDDLE TX COASTAL PLAIN. AN ACCOMPANYING THREAT OF
HAIL...DMGG WIND GUSTS...AND POSSIBLY A TORNADO OR TWO COULD
EXIST...AND MAY REQUIRE ISSUANCE OF A WW.

DISCUSSION...RADAR REFLECTIVITY MOSAIC SHOWS INCREASING COVERAGE OF
PRIMARILY ELEVATED STORMS APPROXIMATELY 30 W HOU WITHIN A WAA
REGIME. ADDITIONAL STORMS OCCURRING JUST E OF THE I-35 CORRIDOR
APPEAR TO BE ROOTED NEAR THE SFC....WITH ONE SUCH STORM ENTERING
FAYETTE COUNTY TAKING A MORE EWD TURN WITHIN THE PAST HALF HR. PW
VALUES NEAR 1.5 INCH COUPLED WITH MODERATELY STRONG MIDLEVEL FLOW
WILL SUPPORT SOME ORGANIZATION WITH THE STRONGEST CORES...SUPPORTIVE
OF A THREAT FOR LARGE HAIL. ADDITIONALLY...A THREAT FOR DMGG WINDS
AND PERHAPS A TORNADO MAY EXIST WITH ANY SFC-BASED STORMS...GIVEN
NEARLY ELY SFC WINDS ENHANCING LOW-LEVEL HELICITY. GIVEN THESE
CONDITIONS...A WW MAY BE REQUIRED SHOULD CONVECTIVE TRENDS CONTINUE
TO INCREASE.

..ROGERS/CORFIDI.. 04/02/2013


ATTN...WFO...HGX...EWX...

[srainhoutx]

E-mail update from Jeff:

SPC has upgraded a large part of SE TX into a slight risk for severe thunderstorms tonight.

The risk area is mainly along and SW of a line from College Station to Houston to High Island or along and SW of the nearly stationary frontal boundary across the region. Breaks in the overcast over C and SC TX have allowed surface temperatures to warm into the upper 70’s to near 80 with dewpoints nearing 70 resulting in an increasingly unstable atmosphere. Thunderstorms have begun to develop in the last few hours near Austin and across Wharton County as large scale lift is starting to work into the area. A severe thunderstorm watch has been issued for much of central TX in response to the recent upward trends in convective developments.

Main severe threat will be large hail, especially initially this afternoon as cells remain discrete. The wind damage threat may increase this evening/overnight as storms congeal into a cluster or line and sweep ESE toward the TX coastal plains.

[srainhoutx]

Severe Thunderstorm Watch issued for SE TX until 11:00 PM

Code: Select all

BULLETIN - IMMEDIATE BROADCAST REQUESTED
     SEVERE THUNDERSTORM WATCH OUTLINE UPDATE FOR WS 80
     NWS STORM PREDICTION CENTER NORMAN OK
     345 PM CDT TUE APR 2 2013
     
     SEVERE THUNDERSTORM WATCH 80 IS IN EFFECT UNTIL 1100 PM CDT
     FOR THE FOLLOWING LOCATIONS
     
     TXC015-039-041-051-071-089-157-167-185-201-291-339-373-407-471-
     473-477-481-030400-
     /O.NEW.KWNS.SV.A.0080.130402T2045Z-130403T0400Z/
     
     TX 
     .    TEXAS COUNTIES INCLUDED ARE
     
     AUSTIN               BRAZORIA            BRAZOS              
     BURLESON             CHAMBERS            COLORADO            
     FORT BEND            GALVESTON           GRIMES              
     HARRIS               LIBERTY             MONTGOMERY          
     POLK                 SAN JACINTO         WALKER              
     WALLER               WASHINGTON          WHARTON             

[srainhoutx]

Folks in Washington County heads up. Severe Storm moving ENE from Fayette County toward Brenham area.

[jasons2k]

It's nice to be right in the middle of the box for a change, instead of on the fringes.

[Andrew]

"Boundary" Seems to be set up just SW of College Station and south of Austin. This should be the focal point for stronger storms especially later when the piece of energy from the west arrives.

[Andrew]

Keep an eye around Gonzalez and points NE. BV is showing 60kt winds

[srainhoutx]

Flash flooding in Smithville has closed many roads via Emergency Manager/Law Enforcement.

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
436 PM CDT TUE APR 2 2013

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
SOUTHERN BASTROP COUNTY...
EAST CENTRAL CALDWELL COUNTY...
WESTERN FAYETTE COUNTY...
EXTREME NORTHEASTERN GONZALES COUNTY...
SOUTH CENTRAL LEE COUNTY...

* UNTIL 730 PM CDT.

* AT 435 PM CDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED FLASH
FLOODING ACROSS THE WARNED AREA. STREET FLOODING HAS BEEN REPORTED
IN SMITHVILLE. ONE TO TWO INCHES OF ADDITIONAL RAINFALL IS LIKELY.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...LA GRANGE...
SMITHVILLE...CISTERN...MULDOON AND ROSANKY.

[srainhoutx]

Breaks in the clouds across S/S Central Texas may spark additional storms during the evening hours as a strong upper level disturbance moves E from Mexico.

[unome]

http://www.spc.noaa.gov/products/watch/ww0080_prob.html

WWUS40 KWNS 022059
WWP0

SEVERE THUNDERSTORM WATCH PROBABILITIES FOR WS 0080
NWS STORM PREDICTION CENTER NORMAN OK
0358 PM CDT TUE APR 02 2013

WS 0080
PROBABILITY TABLE:
PROB OF 2 OR MORE TORNADOES : 20%
PROB OF 1 OR MORE STRONG /F2-F5/ TORNADOES : 10%
PROB OF 10 OR MORE SEVERE WIND EVENTS : 30%
PROB OF 1 OR MORE WIND EVENTS >= 65 KNOTS : 20%
PROB OF 10 OR MORE SEVERE HAIL EVENTS : 50%
PROB OF 1 OR MORE HAIL EVENTS >= 2 INCHES : 20%
PROB OF 6 OR MORE COMBINED SEVERE HAIL/WIND EVENTS : 90%

&&
ATTRIBUTE TABLE:
MAX HAIL /INCHES/ : 2.0
MAX WIND GUSTS SURFACE /KNOTS/ : 60
MAX TOPS /X 100 FEET/ : 500
MEAN STORM MOTION VECTOR /DEGREES AND KNOTS/ : 26020
PARTICULARLY DANGEROUS SITUATION : NO

&&
FOR A COMPLETE GEOGRAPHICAL DEPICTION OF THE WATCH AND
WATCH EXPIRATION INFORMATION SEE WOUS64 FOR WOU0.

$$

[Andrew]

KCLL Special Sounding:

[Portastorm]

Quite a storm here in SW Austin ... very heavy rain and pea-sized hail with wind gusts above 50 mph. Nice to have a real FUNderstorm!

[srainhoutx]

From Nesdis:

SATELLITE PRECIPITATION ESTIMATES..DATE/TIME 04/02/13 2249Z
SATELLITE ANALYSIS BRANCH/NESDIS---NPPU---TEL.301-683-1404
LATEST DATA USED: GOES-13 2230Z KUSSELSON
NOAA AMSU:2050Z DMSP SSMIS:1415Z
.
LOCATION...CENTRAL AND SE TEXAS...
.
ATTN WFOS...HGX...FWD...EWX...
ATTN RFCS...WGRFC...
.
EVENT...CONVECTIVE AREAS FOR TRAINING ALONG OUTFLOW BOUNDARY...
.
SATELLITE ANALYSIS AND TRENDS...BIG CONVECTIVE COMPLEX IN WESTERN GULF
HAS GENERATED A 2.0" MAX OF PRECIPITABLE WATER VALUE CENTERED NEAR 26.5N
AND 93W. NOW WHY MAY THAT BE A CONCERN FOR C TO EASTERN/SE TEXAS.
IT LOOKS LIKE SOME OF THIS HIGH MOISTURE IS GETTING STEERED INTO THE
CENTRAL GULF COAST OF TEXAS AND MAY ALREADY BE SEEPING ALONG WEAK
BOUNDARY NEAR THE COAST AND MATAGORDA COUNTY AND EXTENDING WEAKLY TO
FIRST COMPLEX AFFECTING FAYETTE INTO COLORADO COUNTY. AND IF THAT IS
THE CASE AND PWAT INCREASING TO AT LEAST 1.6"-1.7" AS PER LATEST GOES
SOUNDER...THEN RAIN RATES OF CLOSE TO 2.0" PER HR MAY BE FALLING AT THE
FRONT END OF THE COMPLEX AND JUST BEHIND, ESPECIALLY IF THERE ARE A FEW
CELLS GOIGN OVER ONE SPOT IN THAT HR. THIS FIRST COMPLEX HAS GENERATED
AT OUTFLOW THAT EXTENDS FROM FAYETTE TO BASTROP TO SECOND COMPEX NEAR
TRAVIS COUNTY. SO QUITE CONCERNED ABOUT ANY TRAINING ALONG OUTFLOW
AND HIGHER PWAT MOISTURE BEING ADVECTED BACK ALONG BOUNDARY TO HEIGHTEN
HEAVY RAIN BURSTS INTO FF PRODUCING AREAS TRAVIS TO
LAVACA/FAYETTE/COLORADO COUNTY DURING THE NEXT SEVERAL HRS.
.
AN ANNOTATED SATELLITE GRAPHIC SHOWING THE HEAVY PRECIPITATION THREAT AREA
SHOULD BE AVAILABLE ON THE INTERNET ADDRESS LISTED BELOW IN APPROXIMATELY
10-15 MINUTES.
.
SHORT TERM OUTLOOK VALID 2245-0145Z...MEDIUM TO HIGH CONFIDENCE FACTOR
IN SHORT
TERM OUTLOOK...CONVECTION FROM FIRST COMPLEX PRODUCING VERY HVY RAIN
DRIFTING SLOWLY SE ACROSS LAVACA...FAYETTE...COLORADO COUNTY AND CONCERNED
OUTFLOW TRAINING BETWEEN TRAVIS AND THESE COUNTIES CAN PROVIDE SOME
TRAINING CELLS THAT COULD GIVE ISOLATED SPOTS THAT 3-5" IN SEVERAL HRS
AND HEIGHTEN FF THREAT. SEE GRAPHIC FOR DELINEATION.