Severe Thunderstorm Warning 39, NWS Brownsville, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BROWNSVILLE TX
146 PM CDT MON JUN 1 2009

.DISCUSSION...CONVECTION JUST STARTING TO FIRE ACROSS THE COASTAL
COUNTIES WITH ACTIVITY TO INCREASE THROUGH SUNSET. DO NOT EXPECT
CONVECTION TO GO WIDESPREAD AS UPPER SUPPORT...MAINLY JET
DYNAMICS...WANING OR SHIFTING EAST. AIRMASS TYPE THUNDERSTORMS
WITH INTERACTION WITH OUT FLOW BOUNDARIES SHOULD PROVIDE THE
WIDELY SCATTERED TO SCATTERED ACTIVITY THROUGH THE REMAINDER OF
THE AFTERNOON AND EARLY EVENING HOURS. HEAVY DOWNPOURS SHOULD BE
MAIN HAZARD WITH THESE STORMS...BUT AS WAS THE CASE YESTERDAY CAN
NOT RULE OUT ONE OR TWO THUNDERSTORMS IF CELL MERGERS OR BOUNDARY
INTERACTIONS OCCUR.

UPPER TROUGH TO SHIFT EAST THE NEXT FEW DAYS WITH UPPER RIDGE TO
BUILD OVERHEAD BY FRIDAY BECOMING ESTABLISHED OVER THE WEEKEND.
BOTH GFS AND ECMWF CONSISTENT IN THIS TREND WITH PREVIOUS AND
CURRENT FORECAST ALSO SHOWING PERSISTENCE. RAIN CHANCES TO LOWER
TO SLIGHT CHANCES TO ISOLATED TUESDAY AND WEDNESDAY WITH MAINLY
HEATING AND SEABREEZE TO BE THE TRIGGER NEEDED.

ONCE THE RAIN CHANCES WANE TEMPERATURES SHOULD RISE AS WILL THE
HEAT INDICES. GFS MAV AND MEXMOS LOOK ON TRACK WITH AND WILL
CONTINUE TO TREND IN THIS DIRECTION WITHOUT MUCH VARIATION.

ALL IS QUIET IN THE TROPICS WITH NO SUSPECT AREAS OF NOTE. THIS IS
THE TIME FOR ALL TO LOOK OVER THEIR PREPARATION AND EVACUATION
PLANS. FOR MORE INFORMATION PLEASE GO TO WWW.WEATHER.GOV/RGV AND
CHECK OUT OUR RIO GRANDE VALLEY HURRICANE GUIDE.

&&

.AVIATION...VFR CONDITIONS WITH MODERATE SOUTHEASTERLY WINDS AND
PARTLY CLOUDY TO MOSTLY CLOUDY SKIES ARE BEING REPORTED AT THE
REGIONAL AIRPORTS.  THERE IS A SLIGHT CHANCE FOR SHOWERS AND
ISOLATED THUNDERSTORMS MOVING ACROSS PORTIONS OF THE CWA THIS
AFTERNOON AND EARLY EVENING. ANY SHOWERS OR THUNDERSTORMS MAY
REDUCE CEILINGS AND/OR VISIBILITIES TO TEMPORARY MVFR OR IFR
CONDITIONS. OTHERWISE VFR CONDITIONS WILL PREVAIL ACROSS THE
REGIONAL AIRPORTS DURING THE NEXT 24 HOURS.

&&

.MARINE...AT NOON BUOY 20 REPORTED SOUTHEAST WINDS AT 12 KNOTS
AND SEAS AT 2.6 FEET WITH A 5 SECOND PERIOD. A WEAK PRESSURE
GRADIENT WILL PERSIST ACROSS THE COASTAL WATERS THROUGH THE MIDDLE
OF THIS WEEK. THE WEAK PRESSURE GRADIENT WILL RESULT IN LIGHT TO
MODERATE SOUTHEASTERLY WINDS AND LOW SEAS PREVAILING ACROSS THE
MARINE AREAS THROUGH THE END OF THIS WEEK.  THERE IS A SLIGHT CHANCE
FOR SHOWERS AND ISOLATED THUNDERSTORMS MOVING ACROSS PORTIONS OF THE
MARINE AREAS AT TIMES THROUGH TUESDAY. THE WINDS AND SEAS MAY
INCREASE IN OR NEAR ANY SHOWERS OR THUNDERSTORMS.

&&

.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL  76  90  78  92 /  20  20  10  20
BROWNSVILLE          73  92  74  93 /  20  20  10  10
HARLINGEN            73  92  74  94 /  20  20  10  20
MCALLEN              74  96  76  97 /  20  20  10  10
RIO GRANDE CITY      74  99  74 102 /  20  20  10  10
SOUTH PADRE ISLAND   77  87  78  90 /  20  20  10  10

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&

THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WWW.WEATHER.GOV/BROWNSVILLE

59/63

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BROWNSVILLE TX
430 AM CDT MON JUNE 1 2009

GMZ130-132-135-150-155-170-175-TXZ248>257-021100-
LAGUNA MADRE FROM THE PORT OF BROWNSVILLE TO THE ARROYO COLORADO-
LAGUNA MADRE FROM THE ARROYO COLORADO TO 5 NM NORTH OF PORT
MANSFIELD TX-
LAGUNA MADRE FROM 5 NM NORTH OF PORT MANSFIELD TO BAFFIN BAY TX-
COASTAL WATERS FROM PORT MANSFIELD TO THE RIO GRANDE OUT 20 NM-
COASTAL WATERS FROM BAFFIN BAY TO PORT MANSFIELD OUT 20 NM-
WATERS FROM PORT MANSFIELD TO THE RIO GRANDE EXTENDING FROM 20 TO
60 NM-
WATERS FROM BAFFIN BAY TO PORT MANSFIELD EXTENDING FROM 20 TO
60 NM-ZAPATA-JIM HOGG-BROOKS-KENEDY-STARR-HIDALGO-INLAND WILLACY-
INLAND CAMERON-COASTAL WILLACY-COASTAL CAMERON-
430 AM CDT MON JUNE 1 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR DEEP SOUTH TEXAS...THE GULF
OF MEXICO AND THE LAGUNA MADRE.

.DAY ONE...TODAY AND TONIGHT.

SCATTERED SHOWERS AND THUNDERSTORMS ARE FORECAST DURING THE MORNING
AND AFTERNOON HOURS. ANY STRONGER THUNDERSTORMS MAY PRODUCE LOCALLY
HEAVY RAINFALL AND GUSTY WINDS.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY.

ISOLATED SHOWERS AND THUNDERSTORMS ARE FORECAST TUESDAY THROUGH
THURSDAY. LOCALLY HEAVY RAINFALL AND GUSTY WINDS WILL ACCOMPANY ANY
OF THE HEAVIER THUNDERSTORMS.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTER ACTIVATION IS NOT ANTICIPATED.

TOMASELLI

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BROWNSVILLE TX
300 PM CDT MON JUN 1 2009

TXZ255-012145-
INLAND CAMERON-
300 PM CDT MON JUN 1 2009

...STRONG THUNDERSTORMS WILL AFFECT WESTERN PORTIONS OF CAMERON
COUNTY...

A THUNDERSTORM...MOVING SOUTHEAST AT 5 MPH...WILL AFFECT PRIMERA...
PALM VALLEY...SANTA ROSA AND LA FERIA...UNTIL 445 PM CDT. GUSTY WINDS
UP TO 50 MPH MAY CAUSE LOOSE OBJECTS TO BLOW AROUND. SOME DAMAGE TO
TREE LIMBS AND WIRES IS POSSIBLE. EXCESSIVE CLOUD TO GROUND LIGHTNING
IS EXPECTED IF OUTSIDE...CROUCH DOWN IN A LOW SPOT...AWAY FROM TALL
OBJECTS. IF INDOORS...REFRAIN FROM USING ELECTRICAL APPLIANCES. HAIL
UP TO ONE HALF INCH IN DIAMETER IS EXPECTED. RAINFALL RATES OF 1 TO 2
INCHES PER HOUR WILL OCCUR. MOTORISTS CAN EXPECT PONDING OF WATER ON
ROADS...AND MINOR FLOODING OF POOR DRAINAGE AREAS.

61/MC