Severe Thunderstorm Warning 296, NWS Austin/San Antonio, TX

000 
WWUS54 KEWX 300449
SVSEWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1048 PM CST WED NOV 29 2006

TXC091-300515-
/O.CON.KEWX.SV.W.0296.000000T0000Z-061130T0515Z/
COMAL TX-
1048 PM CST WED NOV 29 2006

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM CST
FOR COMAL COUNTY...

AT 1042 PM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL.
 THIS STORM WAS LOCATED NEAR SPRING BRANCH...OR ABOUT 12 MILES WEST
OF CANYON LAKE DAM...MOVING EAST AT 20 MPH.

THE SEVERE THUNDERSTORM WILL OTHERWISE REMAIN OVER MAINLY RURAL AREAS
OF THE INDICATED COUNTY.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 200 AM CST THURSDAY MORNING
FOR SOUTH CENTRAL TEXAS.

LAT...LON 2977 9863 2974 9845 2983 9831 2994 9843

$$

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
734 PM CST WED NOV 29 2006

.UPDATE...
MADE QUICK UPDATE TO MAKE A FEW ADJUSTMENTS TO CURRENT WEATHER. ALSO
CHANGED THE SLEET ADVISORY TO A WINTER WEATHER ADVISORY WHICH IS
MORE APPROPRIATE GIVEN THE STRONG WINDS AND WIND CHILLS IN
ADDITION TO THE SLEET THURSDAY MORNING.

&&

.PREV DISCUSSION... (ISSUED 557 PM CST WED NOV 29 2006)

AVIATION...
THE CURRENT VFR CONDITIONS WILL LOWER TO MVFR AROUND 03Z...BUT
KDRT WILL REMAIN VFR. SOUTH TO SOUTHEAST WINDS OF 10 TO 15 KNOTS
WILL PREVAIL TONIGHT. A STRONG COLD FRONT WILL MOVE THROUGH THE
TAF SITES BETWEEN 09Z AND 11Z WITH WINDS SHIFTING TO NORTH TO
NORTHWEST AND INCREASING TO 20 TO 25 KNOTS WITH GUSTS 30 TO 35
KNOTS AFTER 13Z. ISOLATED TO SCATTERED SHRA WILL OCCUR THROUGH MUCH OF THE
FORECAST PERIOD...ALTHOUGH TSRA IS POSSIBLE ALONG AND AHEAD OF THE
FRONT BETWEEN 06Z AND 11Z.

PREV DISCUSSION... (ISSUED 512 PM CST WED NOV 29 2006)

DISCUSSION...
THE SUMMARY SECTION OF THIS AFD SAYS IT ALL. A STRONG STORM SYSTEM
DIGGING ACROSS TEXAS WILL PRODUCE A VARIETY OF THREATENING WEATHER
OVER THE NEXT 24-36 HOURS. THIS PAYBACK FOR ALL THE ABOVE NORMAL
DAYS WILL INCLUDE POTENTIAL SEVERE WEATHER...RED FLAG CONDITIONS...
FIRST FREEZE OF THE SEASON...WIND ADVISORY CRITERIA...AND LAST BUT
CERTAINLY NOT LEAST...A SLEET ADVISORY FOR THE NORTHERN PART OF
THE FORECAST AREA.

THE MAIN CONCERN AMID ALL OF THESE THREATS IS THE POTENTIAL FOR
CHANGE. AFTERNOON MODEL RUNS AND LATEST TRENDS OF THE FRONT
REVEALED AN ACCELERATING FRONT TO SIGNAL THE FIRST POTENTIAL ICE
EVENT FOR THE SEASON. THE SLEET ADVISORY ASSUMES ALL AREAS WILL
REMAIN ABOVE FREEZING AND THAT ICE ACCUMULATION ONLY OCCURS ON
BRIDGES AND OVERPASSES WHERE HEAVIER SLEET SHOWERS DEVELOP. THE
NAM/WRF SUGGEST DRIER AIR INTRUDING ON THE HEELS OF THE MOIST
FRONTAL INVERSION TO ENHANCE ANY EVAPORATIVE COOLING EFFECTS.
LIGHT SNOW IS NOT OUT OF THE QUESTION, BUT THE BEST THREAT GIVEN
THE EXPECTED DEPTH OF THE COLD LAYER WAS FOR SLEET. SOME SLEET
COULD BE NOTED FARTHER SOUTH INTO THE AUS METRO AREA...AND POSSIBLY
EVEN THE SAT METRO AREA, BUT DELAYED COOLING SHOULD PRECLUDE
ACCUMULATIONS UNTIL PRECIPIATION RATES WOULD BE TOO LIGHT TO BE
SIGNIFICANT.

THE SEVERE THREAT FOR TONIGHT SHOULD BE MAINLY FOR HAIL...BUT AN
ISOLATED SUPERCELL WITH ALL ASSOCIATED THREATS FOR STRONG WIND...
TORNADOES...AND HEAVY RAIN COULD DEVELOP ALONG THE FRONT. MOST OF
THE SIGNIFICANT RAIN WILL FOCUS EAST OF A ROCKSPRINGS TO
CAMPBELLTON LINE.

AFTER THE WINDS DIE DOWN THURSDAY...THE MODELS SHOULD NEAR OR
BELOW NORMAL TEMPS AND AN ABUNDANCE OF PACIFIC MOISTURE. EXPECT
LESS DRAMA TO ACCOMPANY FUTURE FRONTAL PASSAGES EXPECTED SUNDAY
AND WEDNESDAY. THE ONE CONCERN FOR THESE FRONTS WILL BE FOR
ADDITIONAL ICE EVENTS, THOUGH THE MODELS DO NOT SUGGEST COLD
ENOUGH AIR FOR THESE THREATS. WILL FOLLOW THE REASONABLE GFS ON
THESE NEXT TWO SYSTEMS.

FIRE WEATHER...
GUSTY WINDS AND DRY CONDITIONS SHOULD RESULT IN A THREAT FOR
UNCONTROLLABLE WILDFIRES ACROSS THE SOUTHERN EDWARDS PLATEAU AND
THE RIO GRANDE PLAINS. THERE IS ALSO A SLIGHT POSSIBILITY FOR RED
FLAG CONDITIONS OVER THESE SAME AREAS WHEN THE FRONT FIRST BLOWS
THROUGH THE AREA BETWEEN 2 AND 6 AM.

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 3 AM THURSDAY TO 5 PM THURSDAY FOR THE FOLLOWING
COUNTIES: ATASCOSA... BANDERA... BASTROP... BEXAR... BLANCO...
BURNET... CALDWELL... COMAL... DE WITT... DIMMIT... EDWARDS...
FAYETTE... FRIO... GILLESPIE... GONZALES... GUADALUPE... HAYS...
KARNES... KENDALL... KERR... KINNEY... LAVACA... LEE... LLANO...
MAVERICK... MEDINA... REAL... TRAVIS... UVALDE... VAL VERDE...
WILLIAMSON... WILSON... AND ZAVALA.

WINTER WEATHER ADVISORY FROM 6 AM THURSDAY TO NOON THURSDAY FOR THE
FOLLOWING COUNTIES: BURNET... GILLESPIE... LLANO... AND WILLIAMSON.

FREEZE WARNING FROM 10 PM THURSDAY TO 9 AM FRIDAY FOR THE FOLLOWING
COUNTIES: ATASCOSA... BASTROP... BEXAR... CALDWELL... COMAL... DE
WITT... DIMMIT... FAYETTE... FRIO... GONZALES... GUADALUPE...
HAYS... KARNES... LAVACA... LEE... MAVERICK... TRAVIS...
WILLIAMSON... WILSON... AND ZAVALA.

RED FLAG WARNING FROM 6 AM THURSDAY TO 6 PM THURSDAY FOR THE
FOLLOWING COUNTIES: DIMMIT... KINNEY... MAVERICK... VAL VERDE...
AND ZAVALA.

&&

01/03

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
349 PM CST WED NOV 29 2006

TXZ171>173-183>194-202>209-217>225-228-301130-
LLANO-BURNET-WILLIAMSON-VAL VERDE-EDWARDS-REAL-KERR-BANDERA-
GILLESPIE-KENDALL-BLANCO-HAYS-TRAVIS-BASTROP-LEE-KINNEY-UVALDE-
MEDINA-BEXAR-COMAL-GUADALUPE-CALDWELL-FAYETTE-MAVERICK-ZAVALA-
FRIO-ATASCOSA-WILSON-KARNES-GONZALES-DE WITT-LAVACA-DIMMIT-
349 PM CST WED NOV 29 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH CENTRAL TEXAS.

.DAY ONE...TONIGHT

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ALONG AND EAST OF
A FREDERICKSBURG TO NEW BRAUNFELS TO HALLETTSVILLE LINE TONIGHT.
THE MAIN THREAT WILL BE LARGE HAIL...HOWEVER ISOLATED TORNADOES
AND DAMAGING WINDS ARE ALSO POSSIBLE.

.DAYS TWO AND THREE...THURSDAY AND FRIDAY

A STRONG COLD FRONT WILL MOVE ACROSS SOUTH CENTRAL TEXAS DURING
THE EARLY HOURS ON THURSDAY. TEMPERATURES WILL BRIEFLY DROP TO
NEAR FREEZING ACROSS THE NORTHERN HILL COUNTRY WHICH WILL RESULT
IN A MIX OF RAIN AND SLEET. A WINTER WEATHER ADVISORY WILL HAVE TO
BE ISSUED FOR BURNET...GILLESPIE...LLANO AND WILLIAMSON COUNTIES
FOR THURSDAY MORNING FOR LIGHT ACCUMULATIONS OF SLEET.

STRONG NORTHWEST TO NORTH WINDS OF 20 TO 30 MPH WITH GUSTS TO 40
MPH CAN BE EXPECTED DURING THE DAY. A WIND ADVISORY MAY BE NEEDED
FOR ALL OF SOUTH CENTRAL TEXAS FOR THURSDAY. RELATIVE HUMIDITIES
WILL FALL TO BELOW 25 PERCENT ALONG THE RIO GRANDE. A RED FLAG
WARNING WILL BE ISSUED FOR THE RIO GRANDE PLAINS FOR THURSDAY.

CLEARING SKIES AND MUCH LIGHTER WINDS ALLOW TEMPERATURES TO FALL
TO NEAR OR BELOW FREEZING ACROSS MUCH OF SOUTH CENTRAL TEXAS BY
FRIDAY MORNING. A FREEZE ADVISORY WILL HAVE TO BE ISSUED FOR MUCH
OF SOUTH CENTRAL TEXAS FOR THURSDAY NIGHT INTO FRIDAY MORNING. THE
HILL COUNTRY WILL LIKELY HAVE A HARD FREEZE.

.DAYS FOUR THROUGH SEVEN...SATURDAY THROUGH TUESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED TONIGHT.