AFDBRO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BROWNSVILLE TX
349 AM CDT THU MAY 12 2011

.SHORT TERM /TODAY THROUGH FRIDAY/...WATER VAPOR IMAGERY CONTINUES
TO SHOWS THE DEEP UPPER TROUGH DIGGING ACROSS THE PLAINS AND WEST
TEXAS EARLY THIS MORNING.  HIGH PRESSURE IS SEEN OVER THE EASTERN
STATES.  THESE FEATURES WILL CONTINUE TO GRADUALLY PUSH EAST THROUGH
THE SHORT TERM. AN ASSOCIATED AREA OF LOW PRESSURE IS LOCATED OVER
THE TEXAS AND OKLAHOMA PANHANDLES AND WESTERN KANSAS...WITH A FRONT
STRETCHING SOUTH THROUGH WEST TEXAS.  THIS FEATURE HAS BEEN SLOWLY
NEARING THE CWFA...WHICH HAS ALLOWED THE PRESSURE GRADIENT TO WEAKEN
SOMEWHAT OVER THE AREA.  THEREFORE...WINDS HAVE BEEN WEAKENING
SLIGHTLY THE PAST COUPLE OF DAYS AND SHOULD CONTINUE TO DO SO
THROUGH THE NEXT COUPLE OF DAYS.

LOW LEVEL MOISTURE WILL CONTINUE TO INCREASE OVER THE AREA DUE TO
CONTINUED ONSHORE FLOW.  THIS COMBINED WITH THE FORCING FROM THE
APPROACHING FRONT WILL ALLOW FOR AN INCREASE IN RAIN CHANCES OVER
THE AREA FOR TODAY AND TONIGHT. WITH DECENT MID LEVEL LAPSE RATES
AND SOME INSTABILITY...WILL NOT RULE OUT AN OCCASIONAL STRONG STORM
OR TWO AS THE FRONT NEARS THE AREA. RAIN CHANCES SHOULD BEGIN TO
DIMINISH ON FRIDAY AS THE FRONT BEGINS TO PUSH EAST OF THE AREA AND
THE UPPER LEVEL TROUGH BEGINS TO PUSH EAST OF THE PLAINS.

WITH INCREASED CLOUD COVER OVER THE AREA...TEMPERATURES WILL BE
SLIGHTLY COOLER THAN WE HAVE SEEN THE PAST COUPLE OF DAYS. HIGHS
TODAY SHOULD BE IN THE 90S OVER MOST OF THE VALLEY...WITH THE
EXCEPTION OF THE COASTAL AREAS THAT MAY ONLY STAY IN THE UPPER 80S.
FRIDAY WILL BE SIMILAR OR SLIGHTLY WARMER AS THERE WILL BE LESS
CLOUD COVER AROUND BEHIND THE FRONT.

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...500MB LOW/TROUGH
ACROSS MISSOURI EXTENDING INTO EAST TEXAS AND LOUISIANA FRIDAY
WILL MOVE EASTWARD SATURDAY ALLOWING A 500MB RIDGE TO DEVELOP
ACROSS THE SOUTHWEST UNITED STATES AND TEXAS. NORTHWEST FLOW ALOFT
SHOULD CONTINUE TO PROVIDE SUBSIDENCE ACROSS SOUTH TX THE REST OF
THE WEEKEND INTO EARLY NEXT WEEK. SURFACE HIGH PRESSURE RIDGE
ACROSS THE CENTRAL U.S. THROUGH THE WEEKEND SHOULD PROVIDE NORTHEAST TO
EAST WINDS ACROSS DEEP SOUTH TX THROUGH TUESDAY BEFORE THE RIDGE
MOVES EASTWARD AND LOW PRESSURE DEVELOPS ACROSS WEST TX ALLOWING
MOISTURE TO ADVECT NORTHWARD ACROSS SOUTHWEST TX TOWARDS THE END
OF THE FORECAST PERIOD.
&&

.MARINE...
TODAY THROUGH FRIDAY...MARINE CONDITIONS WILL BE IMPROVING
FOR THE LOWER TEXAS COASTAL WATERS TODAY. AS A RESULT...THE SMALL
CRAFT ADVISORY FOR THE OFFSHORE WATERS IS NO LONGER NEEDED. SCEC
CONDITIONS MAY BE MET FOR THE MORNING HOURS FOR SOME LOCATIONS OVER
THE LOWER TEXAS COASTAL WATERS TODAY.  HOWEVER...WINDS AND SEAS WILL
CONTINUE TO IMPROVE THROUGH THE DAY. WINDS WILL AVERAGE AROUND 15
KNOTS FOR MOST LOCATIONS THROUGH THIS AFTERNOON...BUT SHOULD DROP
MORE INTO THE 10-15 KNOT RANGE FOR TONIGHT AND ON FRIDAY.  AS A
RESULT OF DECREASING WINDS...SEAS WILL ALSO BE LETTING UP...GIVING
MODERATE SEAS THROUGH THE NEXT COUPLE OF DAYS. THERE WILL BE A
SLIGHT CHANCE FOR A FEW SHOWERS AND THUNDERSTORMS TO DEVELOP TODAY
AND TONIGHT...ESPECIALLY FOR THE NORTHERN LOCATIONS AS A FRONT
APPROACHES THE AREA. HOWEVER...MOST OF THIS ACTIVITY SHOULD REMAIN
ON LAND.

FRIDAY NIGHT THROUGH MONDAY...LIGHT EASTERLY WINDS ACROSS THE
COASTAL WATERS FRI NIGHT WILL SHIFT TO THE NORTH AND INCREASE
SATURDAY AS HIGH PRESSURE BUILDS INTO THE WESTERN GULF OF MEXICO.
WINDS SHOULD VEER TO THE NORTHEAST AND DIMINISH AS THE PRESSURE
GRADIENT WEAKENS ACROSS THE WESTERN GULF. LIGHT TO MODERATE
NORTHEAST WINDS WILL PREVAIL THROUGH MONDAY AS HIGH PRESSURE
CONTINUES TO PREVAIL ACROSS THE CENTRAL UNITED STATES.
&&

.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL  89  77  90  72 /  20  20  10  10
BROWNSVILLE          90  77  91  72 /  20  20  10  10
HARLINGEN            92  76  93  72 /  20  20  10  10
MCALLEN              93  77  96  72 /  20  20  10  10
RIO GRANDE CITY      96  74 101  73 /  30  20  10  10
SOUTH PADRE ISLAND   87  75  88  73 /  20  20  10  10
&&

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

$$