Severe Thunderstorm Warning 17, NWS Brownsville, TX

DEEP SOUTH TEXAS FORECAST DISCUSSION...CORRECTED TEMPS
NATIONAL WEATHER SERVICE BROWNSVILLE TX
220 PM CDT TUE JUN 25 2002

.DISCUSSION...FOR THE SHORT-TERM...MODELS CONTINUE THE SAME TREND OF
THE PAST FEW DAYS. UPPER LOW OVER EAST TEXAS...ARKANSAS...LOUISIANA
WILL CONTINUE TO DRIFT WESTWARD AND SETTLE ACROSS THE AREA AS AN
OPEN TROUGH AND SUBSEQUENT AREA OF WEAKNESS. UPPER RIDGE BUILDING
OVER THE WEST SUPPORTS THIS SCENARIO.

THE SUBSEQUENT INCREASING SOUTHEAST FLOW WILL ALLOW GRADUALLY
INCREASING MOISTURE TO AFFECT THE REGION. THUS...THE INHERITED
TREND OF GRADUALLY INCREASING PROBABILITIES OF PRECIPITATION IS
SUPPORTED AND APPEARS REASONABLE. THIS MOISTURE...COMBINED WITH SEA
BREEZE INTERACTIONS...SHOULD ALLOW FOR AT LEAST ISOLATED SHOWERS AS
SOON AS TOMORROW. HAVE INSERTED A VERY MODEST DOWNWARD TREND IN HIGH
TEMPERATURES WITH THIS INCREASING MOISTURE.

.EXTENDED FORECAST...AVN/MRF ARE STILL SHOWING AN INVERTED TROUGH
AFFECTING THE REGION OVER THE WEEKEND. THIS APPEARS TO BE THE
REMNANT OF A TROUGH THAT WAS OVER THE SOUTHERN GULF OVER THE
WEEKEND. WE ARE STILL QUITE SKEPTICAL OF THIS SOLUTION BUT THE
INCREASING QPF FORECAST WAS ENOUGH TO MAKE US TAKE NOTICE.
THUS...HAVE TRENDED THE RAIN CHANCES UPWARD OVER THE WEEKEND...
ESPECIALLY ON SUNDAY OFFSHORE AND OVER THE EASTERN RIO GRANDE
VALLEY. ALTHOUGH THE QPF FORECASTS ARE LIKELY TOO AGGRESSIVE...THE
INCREASED SOUTHEAST FLOW ALONE SHOULD SUPPORT THE SLIGHTLY HIGHER
POPS. THINGS LOOK TO DRY OUT THE BEGINNING OF NEXT WEEK UNDER
RIDGING ALOFT.

.MARINE...5H LOW NOW OVER THE ARKLATX AREA WILL EVENTUALLY DEVOLVE
INTO A WEAKNESS OVER DEEP SOUTH TEXAS TOWARD THE END OF THE WEEK AS
RIDGING SIMULTANEOUSLY BUILDS OVER THE SOUTHWEST. MODERATE SOUTH TO
SOUTHEAST WINDS WILL PREVAIL OVER THE LOWER TEXAS COASTAL WATERS AS
THE BERMUDA HIGH CONTINUES TO EXHIBIT STRENGTH INTO THE GULF OF
MEXICO. MORE PERSISTENT ISOLATED SHOWERS COULD DEVELOP BEGINNING
WEDNESDAY NIGHT AS INCREASED INSTABILITY WORKS SOUTH DOWN THE TEXAS
COAST ALONG AN ELONGATING SHEAR AXIS. SOME CONCERN BY THE WEEKEND AS
AN INVERTED UPPER TROUGHING SETS UP OVER THE EAST COAST OF
MEXICO...SPARKING CONVECTION IN THE BAY OF CAMPECHE AND SOUTHWEST
GULF. UPPER WINDS MAY BE MORE CONDUCIVE TO ALLOWING SOME CONVECTION
TO WORK NORTH INTO THE COASTAL WATERS FOR FRIDAY THROUGH SUNDAY. THE
AVN SEEMS TO LATCH ONTO THIS IDEA WITH THE BEST SHOT AT SOME
SCATTERED SHOWERS OVER THE COASTAL WATERS FOR SATURDAY AND SUNDAY.
NOGAPS ENSEMBLE SUPPORTS THIS SOLUTION.

BRO BB 076/094 077/093 078 00/10/10/20/10
HRL BB 074/096 075/095 076 00/10/10/20/10
MFE UB 076/098 077/097 078 00/10/10/20/10
RGC UB 076/101 076/100 077 00/10/00/10/10
SPI BB 080/089 081/088 081 05/10/10/20/10

SYNOPTIC...52
AVIATION-MARINE-MESO...54...MARTINEZ

INTERNET ADDRESS...WWW.SRH.NOAA.GOV/BRO

.BRO...NONE.