Severe Thunderstorm Warning 55, NWS Houston/Galveston, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
307 PM CDT TUE MAY 1 2007

.DISCUSSION...
FIRST BATCH OF SHOWERS AND THUNDERSTORMS MOVED ACROSS THE NORTHERN COUNTIES
OF SOUTHEAST TEXAS THIS MORNING AND EARLY THIS AFTERNOON. A SECOND BATCH
OF SLIGHTLY WEAKER ACTIVITY...SIMILARLY LINED UP LIKE THIS MORNINGS
STORMS...IS GETTING READY TO MOVE ACROSS THE SAME AREA AGAIN. AS LONG
AS THESE STORMS CONTINUE TO PROGRESS EASTWARD ACROSS THE AREA...DO NOT
SEE MUCH OF A FLOOD THREAT. WILL CONTINUE TO MONITOR THIS AREA. FURTHER
SOUTH...CAP HAS HELD STRONG TODAY. FOR TONIGHTS POPS...WILL OBVIOUSLY
GO WITH HIGHER NUMBER UP NORTH AND TAPER THEM DOWN TO NEAR NOTHING ALONG
THE COAST. THINK THAT THE BEST CHANCE TO SEE ANY RAIN ACROSS SOUTHEAST
TEXAS TONIGHT WILL BE IN THE EVENING. WITH THE MID/UPPER LEVEL LOW STILL
SPINNING ACROSS NORTH CENTRAL OKLAHOMA...ADDITIONAL CONVECTION COULD
DEVELOP SOMEWHERE ACROSS NORTH CENTRAL OR NORTH TEXAS OVERNIGHT...AND
SOME OF THIS ACTIVITY COULD SCRAPE SOME OF OUR NORTHERN COUNTIES. TOMORROWS
WEATHER WILL BE DICTATED BY WHERE AND WHEN WE SEE ANY MORE MCS DEVELOPMENT
WITH THIS STORM SYSTEM. AREA POPS WILL BE LOWER THAN TODAY WITH LOW
END CHANCE UP NORTH AND NONE NEAR THE COAST. WEDNESDAY NIGHT AND THURSDAY
WILL BE OUR NEXT BEST CHANCE FOR RAIN AS A SHORTWAVE MOVES EASTWARD
ACROSS THE STATE. HAVE GONE WITH 50% POPS AREAWIDE ON THURSDAY FOR THIS
DISTURBANCE...AND THIS WILL BE THE BEST SHOT FOR RAINFALL ACROSS THOSE
CENTRAL AND COASTAL LOCATIONS THAT HAVE REMAINED DRY FOR ALMOST SIX
STRAIGHT DAYS. LOWER HIGH TEMPERATURES CAN BE EXPECTED ON THURSDAY DUE
TO THE EXPECTED RAINS. AS THE SHORTWAVE MOVES EASTWARD THURSDAY
NIGHT...SOUTHEAST TEXAS WILL DRY OUT. WITH A MID/UPPER LEVEL RIDGE
THEN BUILDING ACROSS THE AREA...ANTICIPATE DRY AND WARM WEATHER FRIDAY
THROUGH MONDAY. THE UPCOMING WEEKENDS WESTERN U.S. TROUGH WEAKENS AND
LIFTS NORTHEASTWARD EARLY NEXT WEEK WELL AWAY FROM OUR AREA. NEXT TUESDAYS
20% POPS MIGHT ACTUALLY END UP BEING TOO HIGH. 42
&&

.AVIATION...
BAND OF THUNDERSTORMS WILL CONTINUE TO MOVE NORTH OF KCXO BUT AFFECT
KUTS AND POINTS EAST.  CONVECTION TO COME TO AN END AT KCLL BUT MAY
HAVE TO KEEP AN EYE ON ANOTHER BAND OF CONVECTION TO THE NW.  THIS
BAND COULD SKIRT KCLL AND KUTS.  WILL HAVE TO AMEND TAF AT BOTH
SITES SHOULD THIS BE THE CASE.  OTHERWISE...CONVECTION SHOULD STAY
NORTH OF ALL THE HOUSTON AREA TERMINALS AND GULF COAST.  ONSHORE
FLOW WILL KEEP MAINLY BKN LOW CLOUDS ACROSS THE AREA WHICH COULD
SCATTER OUT IN THE EVENING.  EXPECT LOW CLOUDS AND POSSIBLY SOME
LOWER VSBY IN THE MORNING.  EXPECT MVFR CONDITIONS TO LIFT AFTER 15Z
WITH SOUTHEAST WINDS.

39

&&

.MARINE...
WILL CONTINUE SCEC FOR 20NM OUT AREAS AS 15KT WINDS AND 5FT SEAS
SHOULD CONTINUE TO NIGHT.  NEARSHORE WATERS MAY APPROACH SCEC
CONDITIONS BUT WILL HOLD OFF FOR NOW.  OTHERWISE...WINDS SHOULD
DIMINISH SOME TOMORROW BUT PICK UP TOWARDS THE END OF THE WEEK.
SEAS MAY BUILD TO SCA LEVELS FRI/SAT BUT WILL BE MARGINAL.
OTHERWISE...NO OTHER MARINE HAZARDS TO MENTION.

39

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      66  84  68  79  67 /  50  30  30  50  20
HOUSTON (IAH)              67  84  68  79  68 /  40  20  20  50  30
GALVESTON (GLS)            71  81  72  79  72 /  10  10  10  50  30
&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SCEC ALL 20-60 NM WATERS THROUGH 6 AM.
&&

DISCUSSION...42
AVIATION/MARINE...39

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
759 AM CDT TUE MAY 1 2007

TXZ163-164-176>179-195>200-210>214-226-227-235>238-021300-
AUSTIN-BRAZORIA-BRAZOS-BURLESON-CHAMBERS-COLORADO-FORT BEND-
GALVESTON-GRIMES-HARRIS-HOUSTON-JACKSON-LIBERTY-MADISON-MATAGORDA-
MONTGOMERY-POLK-SAN JACINTO-TRINITY-WALKER-WALLER-WASHINGTON-
WHARTON-
759 AM CDT TUE MAY 1 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

.DAY ONE...TODAY AND TONIGHT
THE STORM PREDICTION CENTER HAS PLACED PARTS OF SOUTHEAST TEXAS IN
THE SLIGHT RISK AREA FOR SEVERE THUNDERSTORMS TODAY. THIS REGION
IS MAINLY ALONG AND NORTH OF A LINE FROM BRENHAM TO GROVETON.
STORMS THAT DEVELOPED OVERNIGHT ACROSS CENTRAL TEXAS ARE EXPECTED
TO MOVE INTO THE AREA THIS AFTERNOON AND INTERACT WITH THE WARM
FRONT AND DEEP GULF MOISTURE ALREADY IN PLACE. HOWEVER THERE ARE
CONCERNS REGARDING THE STRENGTH OF THE CAP. SHOULD SEVERE STORMS
DEVELOP...THE PRIMARY SEVERE WEATHER THREATS WILL BE STRONG
DAMAGING WINDS AND LARGE HAIL.

HEAVY RAINS YESTERDAY HAVE SATURATED THE GROUNDS OVER THE
NORTHERN HALF OF SOUTHEAST TEXAS. ANY ADDITIONAL DEVELOPMENT LATER
TODAY OVER THESE SAME AREAS COULD PRODUCE LOCALIZED FLOODING ONCE
AGAIN THIS AFTERNOON AND EVENING.

ALL OF THIS ACTIVITY IS EXPECTED TO WEAKEN BY THIS EVENING.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY
ANOTHER ROUND OF STORMS IS POSSIBLE THURSDAY AS ANOTHER UPPER
LEVEL STORMS SYSTEM MOVES ACROSS THE STATE. NO HAZARDOUS WEATHER
IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON.