Hail and Damaging Wind in Texas, December 30, 2002

DEEP SOUTH TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BROWNSVILLE TX
130 PM CST MON DEC 30 2002

TONIGHT THRU THU...FORECAST PRESENTS AN IMMEDIATE CHALLENGE DURING
THE FIRST 12-HR PERIOD. CWA WILL BE RIGHT ON THE EDGE OF A RAPIDLY
DEVELOPING SEVERE WX SCENARIO. VAD WIND PROFILE SHOWS MID LEVELS
BEGINNING TO DRY OUT AS SW FLOW STRENGTHENS OVER THE SIERRA MADRE.
MORNING 88D LOOP SHOWED LIGHT SHRA SITUATED OVER THE NERN CWA
MIRRORING THIS TREND AND DIMINISHING IN AREAL COVERAGE AND INTENSITY
AS THEY PULLED OUT TO THE NE. FEEL STRONG SIERRA MADRE DOWNSLOPING
WILL SUPPRESS DEEP CONVECTION OVER MUCH OF THE SW CWA. LOW LEVEL JET
UP TO 50 KT IS HELPING TO FEED IN ADDITIONAL LOW LEVEL MOISTURE. AM
SOUNDING SHOWS AN LI OF -5, WITH A PW OF 1.3. STRONG CAP IS ALREADY
IN PLACE...WITH CONVECTIVE TEMP NEAR 100. HOWEVER...WV IMAGERY SHOWS
VERY IMPRESSIVE H5 VORT SE OF ELP. SHARP UPSTREAM TROF DIGGING INTO
THE EPAC JUST W OF CA IS CAUSING RAPID DOWNSTREAM DEVELOPMENT OF THE
H5 RIDGE...WHICH IN TURN IS HELPING TO DIG THE H5 TROF OVER THE
SOUTHERN ROCKIES EVEN FARTHER SOUTH. AGREE WITH MODEL SOLUTIONS
BEGINNING TO FORM A CLOSED H5 LOW NEAR THE VORT CENTER IN W TX. BOTH
THE AVN/MESOETA INITIALIZE WELL WITH THIS FEATURE AT 12Z. FOR THE
SHORT TERM...AGREE WITH THE MODEL SOLUTIONS ALLOWING THE SIERRA
MADRE DOWNSLOPING TO WIN OUT DURING THE NEAR TERM. MID LEVEL DRYING
HAS SCOURED OUT PM CLOUDS OUT WEST...ALLOWING TEMPS TO RISE ABOVE
80. AS SUNSET APPROACHES...VERY STRONG UPPER LEVEL DYNAMICS WILL
BEGIN TO IMPINGE UPON SLIGHTLY DEEPER LOW LEVEL MOISTURE OVER THE
ERN CWA. FORECAST CHALLENGE WILL BE HOW QUICKLY THE POWERFUL UPPER
LEVEL DYNAMICS WILL BREAK DOWN THE CAP. MESOETA ACTUALLY PROGS A
VORT MAX NEAR 52 NEAR THE H5 CUTOFF AT 09Z...CANNOT RECALL SEEING A
VALUE THIS HIGH BEFORE IN THE MODEL FIELDS. SITUATION WILL HAVE TO
BE WATCHED CLOSELY...WITH MOST OF CWA IN SLIGHT RISK AREA. BEST
CHANCE FOR SVR WX WILL BE OVER THE OFFSHORE WATERS AND KENEDY
COUNTY. MESOETA SFC THETA-E FIELDS SUGGEST THETA-E RIDGE WILL SET UP
OVER THE LOWER VALLEY...INCREASING THE RISK OF LATE DAY TSTM
DEVELOPMENT OVER ERN WILLACY AND CAMERON COUNTIES. SIERRA MADRE RAIN
SHADOW LESSENS THE FARTHER E YOU GO...SO BELIEVE LINE OF CONVECTION
WILL DEVELOP TO THE N OF THE CWA BY 00Z...THEN RAPIDLY
BUILD/PROPAGATE SOUTHWARD CLOSE TO THE COAST. WILL CARRY SLIGHT
CHANCE POPS OUT W FOR EARLY TONIGHT...WITH CHANCE POPS RIGHT ALONG
THE COAST. STRONG PAC FRONT/DEVELOPING SQLN SHOULD CLEAR THE
OFFSHORE WATERS BY MIDNIGHT. BEHIND THE FRONT...SPG WILL REMAIN
TIGHT. WILL GO FOR WINDY CONDITIONS E...WITH BREEZY W TUE AM. STRONG
NVA WILL CALL FOR CLEARING SKIES. DEPARTING H5 COLD POOL WILL CAUSE
MOSTLY CLOUDY AM SKIES E...AND PARTLY CLOUDY W. SPG BECOMES NEARLY
FLAT TUE NITE...SO WILL GO FOR LIGHT AND VARIABLE WINDS. AIRMASS
LOOKS TOO DRY FOR MENTION OF FOG. WED LOOKS RATHER WARM...WITH LIGHT
SW SFC FLOW AHEAD OF APPROACHING PAC BNDRY. FROPA EARLY WED NITE
WILL BE DRY...WITH NO RETURN FLOW MOISTURE TO WORK WITH.

THU THRU SUN...GFS CONTINUES TO PROG BREEZY WINDS BEHIND THE NEXT
FRONT. WILL GO FOR MAINLY CLEAR SKIES H5 FLOW STILL FROM THE WNW.
SFC HIGH MOVES OFFSHORE FRI...WITH SOME RETURN FLOW MOISTURE FINALLY
APPEARING SAT. 3RD PAC BNDRY IN THE SERIES LOOKS VIGOROUS IN THE GFS
ALSO. WITH MORE LOW LEVEL MOISTURE TO WORK WITH...AM TEMPTED TO GO
FOR SLIGHT CHANCE POPS ASSOCIATED WITH FROPA DURING THE DAY SUN...
BUT NCEP ENSEMBLES SUGGEST GFS SOLUTION IS TOO AMPLIFIED WITH ASSOC
SHORT WAVE...SO WILL STAY WITH MOSTLY CLOUDY SKIES.

MARINE...BOY020 CONTINUES WITH WINDS AT 14023G29KT AND SEAS AT 8
FEET. STRONG SOUTH WINDS AHEAD OF A COLD FRONT WILL CONTINUE OVER
THE COASTAL WATERS THIS EVENING. ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS...SOME POSSIBLY SEVERE...WILL ALSO BE ON TAP LATE
TODAY AND THIS EVENING ALONG THE FRONT. IN THE WAKE OF THE COLD
FRONT...STRONG NORTH WINDS AND COOLER TEMPERATURES WILL BE THE RULE.
SMALL CRAFT ADVISORIES WILL LIKELY BE IN EFFECT THROUGH TUESDAY.
ANOTHER COLD FRONT COULD CAUSE STRONG NORTH WINDS ONCE AGAIN BY
THURSDAY.

PRELIMINARY NUMBERS FOR COORDINATION PURPOSES ONLY...
BRO NU 054/073 046/076 052 30/00/00/00/00
HRL NU 052/074 046/076 049 30/00/00/00/00
MFE NU 050/075 045/078 049 20/00/00/00/00
RGC UU 048/074 044/076 047 10/00/00/00/00
SPI NU 057/069 052/072 055 40/00/00/00/00

.BRO...WIND ADVISORY UNTIL 500 PM FOR ALL OF DEEP SOUTH TEXAS.
       SCA GMZ130-150-155-170-175.

PUBLIC...62/AVIATION-MARINE-MESO...52

THIS PRODUCT IS ALSO AVAILABLE ON OUR INTERNET WEB PAGE AT
HTTP://WWW.SRH.NOAA.GOV/BRO

GMZ130-150-155-170-175-TXZ248>257-311200-

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE BROWNSVILLE TX
525 PM CST MON DEC 30 2002

THIS HAZARDOUS WEATHER OUTLOOK IS FOR DEEP SOUTH TEXAS.

.DAY ONE...TODAY AND TONIGHT

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR ALL OF DEEP SOUTH TEXAS
UNTIL 1000 PM. SMALL CRAFT ADVISORIES ARE IN EFFECT FOR THE LOWER
TEXAS COAST GULF WATERS AS WELL AS THE LAGUNA MADRE THROUGH TONIGHT.
A STRONG COLD FRONT IS MOVING THROUGH DEEP SOUTH TEXAS AND WILL PUSH
OFF THE LOWER TEXAS COAST THIS EVENING. AN ABRUPT WIND SHIFT FROM
SOUTH TO NORTHWEST WILL OCCUR WITH THE PASSAGE OF THE FRONT, AND
STRONG GUSTY WINDS TO 45 MPH. ISOLATED THUNDERSTORMS ARE POSSIBLE
THIS EVENING. ANY THUNDERSTORMS THAT DO DEVELOP HAVE A HIGH
POTENTIAL TO BECOME SEVERE. SEVERE THUNDERSTORMS MAY PRODUCE
TORNADOES WITH LITTLE OR NO WARNING.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

SMALL CRAFT ADVISORIES FOR THE LOWER TEXAS COASTAL WATERS AND THE
LAGUNA MADRE WILL CONTINUE TUESDAY AS STRONG NORTH WINDS DRIVE SEAS
TO 9 FEET OR HIGHER. THE WINDS AND SEAS WILL DECREASE BY TUESDAY
NIGHT TO BELOW SMALL CRAFT CRITERIA AS HIGH PRESSURE DOMINATES THE
AREA. A SECOND COLD FRONT IS EXPECTED LATE WEDNESDAY NIGHT. WINDS
AND SEAS FOLLOWING THIS FRONT WILL LIKELY WARRANT SMALL CRAFT
ADVISORIES.

.SPOTTER CALL TO ACTION STATEMENT...

SPOTTER ACTIVATION IS POSSIBLE THIS AFTERNOON AND EVENING. EMERGENCY
MANAGERS ARE ASKED TO MONITOR WEATHER CONDITIONS CLOSELY.

TXZ248>257-310400-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BROWNSVILLE TX
525 PM CST MON DEC 30 2002

...A SEVERE THUNDERSTORM WATCH IS IN EFFECT THROUGH 1000 PM...

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR ALL OF DEEP SOUTH TEXAS
THROUGH 1000 PM. THIS WATCH INCLUDES STARR, ZAPATA, JIM HOGG,
BROOKS, HIDALGO, KENEDY, WILLACY, AND CAMERON COUNTIES. SOME CITIES
INCLUDED IN THIS WATCH ARE ZAPATA, HEBBRONVILLE, MCALLEN,
RAYMONDVILLE, FALFURRIAS, SARITA, RIO GRANDE CITY, BROWNSVILLE, AND
SOUTH PADRE ISLAND.

THUNDERSTORMS HAVE THE POTENTIAL TO PRODUCE LARGE HAIL UP TO 2
INCHES IN DIAMETER AND DAMAGING WINDS IN EXCESS OF 60 MPH. DEADLY
LIGHTNING IS ALSO POSSIBLE WITH ANY STORMS THAT DEVELOP.

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.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BROWNSVILLE, TX
608 PM CST MON DEC 30 2002

TIME(CST)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0524 PM    4 E EL SAUZ               TX   60 WIND GUST
12/30/02   STARR                          WIND GUST TO 60 MPH WAS
                                          REPORTED BY THE AEROSTAT
                                          FACILITY

0548 PM    LA GLORIA                 TX   .75 INCH HAIL
12/30/02   STARR                          WEATHER SPOTTER REPORTED
                                          HAIL 3/4 INCH IN DIAMETER