Severe Thunderstorm Warning 49, NWS Corpus Christi, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CORPUS CHRISTI TX
1120 PM CDT WED MAY 27 2009

.DISCUSSION...SEE THE AVIATION DISCUSSION BELOW FOR MORE DETAILS.

&&

.AVIATION...ONGOING CONVECTION ACROSS THE RIO GRANDE PLAINS WL
PRODUCE MVFR/IFR CONDITIONS ACROSS LAREDO FOR MUCH OF THE MORNING.
THIS CONVECTION WL SLOWLY MOVE EWD THROUGH THURSDAY MORNING
ACROSS SOUTH TX. HOWEVER...MOST OF THE CEILINGS ARE EXPECTED TO
REMAIN ABV MVFR CRITERIA GIVEN THE DRIER AIRMASS IN PLACE DUE TO
EARLIER CONVECTION IN THE DAY. BRIEF MVFR CONDITIONS ARE EXPECTED
ACROSS THE NORTHEAST COASTAL BEND (VCT TAF SITE) BETWEEN 09Z AND
15Z THU AS LIGHT FOG DEVELOPS. BRIEF MVFR/IFR CONDITIONS WITHIN
CONVECTION WL STILL BE POSSIBLE THROUGH 22Z THURSDAY. VFR
CONDITIONS WL PREVAIL TMW NIGHT AS EVEN DRIER AND MORE STABLE
CONDITIONS PUSH INTO THE AREA.

&&

.PREV DISCUSSION... /ISSUED 838 PM CDT WED MAY 27 2009/

DISCUSSION...SEVERAL CLUSTERS OF STRONG TO SEVERE CONVECTION
CONTINUE TO FIRE JUST TO THE NORTHWEST AND WEST OF THE RIO GRANDE
PLAINS THIS EVENING. THIS CONVECTION IS BEING AIDED BY THE LEFT-FRONT
QUAD OF A 70-80 KT JET STREAK MOVING THROUGH CENTRAL MEXICO AND
SVRL CONVECTIVE OUTFLOWS MOVING THROUGH THIS RGN. THE LATEST LAPS
DATA INDICATE SFC-BASED CAPES AVERAGING 2500-3500 J/KG WITH A WEAK
CAP. EXPECT THESE CLUSTERS OF STORMS TO EVENTUALLY PROPAGATE INTO
THE RIO GRANDE PLAINS DURING THE EVENING HOURS BASED UPON THE MEAN
STEERING CURRENTS AND CONVECTION BUILDING TWDS THE HIGHER
INSTABILITY WHICH EXIST ACROSS THIS RGN. BLV LARGE HAIL AND GUSTY
WINDS WL BE THE MAIN THREAT ALONG WITH TORRENTIAL RAIN. BLV MOST
OF THIS ACTIVITY WL LINGER THROUGH THE FIRST HALF OF TNT.
ALTHOUGH...EXPECT CONVECTION TO EVEN LINGER AFTER MIDNIGHT ACROSS
THIS RGN GIVEN THE DYNAMIC SUPPORT THAT EXISTS. FURTHER EAST...BLV
THE AIRMASS WL BE TOO STABLE AND WORKED OVER FROM PREVIOUS STORMS
FOR CONVECTION TO OCCUR TNT. WL THUS DROP POPS ACROSS THE ERN
AREAS AND THE WATERS FOR TNT.

MARINE...BUOY 42020 CONTINUES TO REPORT 6 FT SEAS WHICH WAS
MOSTLY DUE TO EARLIER STRONG THUNDERSTORM WINDS. AS THE WINDS
CONTINUE TO COME DOWN TNT...THE SEAS WL SLOWLY COME DOWN TOO.
WITH THE OVERALL GRADIENT REMAINING QUITE WK...NO FLAGS ARE
EXPECTED.

&&

.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI    72  88  70  89  68  /  10  40  10  20  10
VICTORIA          68  88  67  91  65  /  10  30  10  10  10
LAREDO            76  94  75  94  73  /  40  40  20  20  10
ALICE             71  92  69  91  68  /  10  40  10  20  10
ROCKPORT          74  86  71  88  72  /  10  30  10  10  10
COTULLA           70  91  69  93  68  /  40  40  20  10  10
KINGSVILLE        72  92  68  90  68  /  10  40  10  20  10
NAVY CORPUS       76  87  72  86  72  /  10  40  10  20  10

&&

.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.

&&

MB

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE CORPUS CHRISTI TX
329 PM CDT WED MAY 27 2009

GMZ230-235-250-255-270-275-TXZ229>234-239>247-281200-
BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT ARANSAS-
BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT OCONNOR-
COASTAL WATERS BAFFIN BAY TO PORT ARANSAS OUT 20 NM-
COASTAL WATERS PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM-
WATERS BAFFIN BAY TO PORT ARANSAS 20 TO 60 NM-
WATERS PORT ARANSAS TO MATAGORDA SHIP CHANNEL 20 TO 60 NM-
LA SALLE-MCMULLEN-LIVE OAK-BEE-GOLIAD-VICTORIA-WEBB-DUVAL-
JIM WELLS-KLEBERG-NUECES-SAN PATRICIO-ARANSAS-REFUGIO-CALHOUN-
329 PM CDT WED MAY 27 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH TEXAS AND THE MIDDLE
TEXAS COASTAL WATERS.

.DAY ONE...THIS AFTERNOON AND TONIGHT

AN OUTFLOW BOUNDARY FROM STRONG THUNDERSTORMS IN THE COASTAL BEND
WILL CONTINUE TO DRIFT WEST ACROSS THE RIO GRANDE PLAINS AND VALLEY.
THIS IN COMBINATION WITH SIERRA MADRE CONVECTION MOVING EAST OUT
OF MEXICO DUE TO STRONG HEATING AND A WEAK UPPER LEVEL DISTURBANCE
WILL PROVIDE SCATTERED THUNDERSTORMS ALONG THE RIO GRANDE VALLEY
OVERNIGHT. THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS
PRODUCING LARGE HAIL AND DAMAGING WINDS ASSOCIATED WITH THIS
ACTIVITY.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

SCATTERED THUNDERSTORMS ARE EXPECTED ONCE AGAIN ON THURSDAY AS A
WEAK UPPER LEVEL DISTURBANCE AND JET STREAM INTERACT WITH HIGH
MOISTURE AND INSTABILITY ALONG A WEAK FRONTAL BOUNDARY AND THE SEA
BREEZE. GIVEN ADEQUATE HEATING A FEW STORMS MAY BECOME SEVERE
PRODUCING LARGE HAIL AND DAMAGING WINDS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED.

MJG