Red Flag Warning 2, NWS Brownsville, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BROWNSVILLE TX
324 AM CST THU JAN 31 2008

.DISCUSSION...LOW TO MID LEVEL MOISTURE SHOULD INCREASE TONIGHT
INTO THURSDAY MORNING BEFORE A 500MB SHORTWAVE TROUGH DEVELOPS
OVER THE SOUTHERN ROCKIES AND MOVES INTO THE SOUTHERN PLAINS. THIS
WILL BRING SURFACE LOW PRESSURE OVER NORTHWEST TEXAS EASTWARD WITH
A SIGNIFICANT COLD FRONT ACROSS THE STATE THURS MORNING. FOG IS
EXPECTED TO DEVELOP TONIGHT INTO EARLY THURSDAY AHEAD OF THE
FRONT. REFRESHED THE GRIDS WITH THE LATEST 00Z MODEL DATA IN THE
FOLLOWING WAY. POPULATED TEMPERATURES WITH THE ADJMEX MODEL AND
MANUALLY LOWERED TEMPERATURES AS MUCH AS FIVE TO SIX DEGREES IN
THE NORTHERN PORTIONS OF THE INTERIOR CWA FOR THE DAYBREAK HOURS OF
FRIDAY MORNING. SINCE A WARM BIAS HAS BEEN OBSERVED IN THE
GUIDANCE THIS WINTER SEASON WITH LOW TEMPERATURES DUE TO AN
OVERESTIMATE OF THE DEW POINT TEMPERATURES ESPECIALLY WITH ARCTIC
MASSES ... ALSO LOWERED THE DEW POINT TEMPERATURES BY THE SAME
AMOUNT AS THE TEMPERATURE FOR THE NORTHERN AND INTERIOR PORTIONS
OF THE CWA. LOADED HPC QPF GUIDANCE FOR THE SHORT TERM PERIOD
SINCE THE PRECIPITATION MODEL GUIDANCE APPEARS A BIT OVERDONE.
ALSO ADDED FOG FOR THE MORNING HOURS OF AND DAYBREAK OF THIS
MORNING.

&&

.MARINE...BUOY020 CHECKS IN TODAY WITH FAIRLY BENIGN MARINE
CONDITIONS WITH A SE WIND AROUND 16 KTS WITH SWELLS AROUND 6 FT.
THE MARINE CONDITIONS WILL BEGIN TO DETERIORATE LATER TODAY IN
RESPONSE TO THE INCREASING NORTHWESTERLY SURFACE FLOW BUILDING IN
THE WAKE OF THE EXPECTED FROPA OVER THE REGION THIS MORNING.  THIS
INCREASE IN THE WIND AND SWELL ACTIVITY WILL BE FAIRLY SHORT LIVED
AS A WEAKER PGF PREVAILS ON FRI ALLOWING THE WINDS AND SEAS TO
SLACKEN INTO FRI NIGHT.  THEN THE INCREASE OF BROAD 500 MB TROFFING
OVER THE CENTRAL U.S. WILL THEN TIGHTEN UP THE PGF INTO THIS WEEKEND
RESULTING IN A STRONGER SOUTHERLY LOW LEVEL WIND FLOW. ANOTHER COLD
FRONT WILL MOVE OVER THE REGION NEXT TUES SHIFTING THE LOW LEVEL
FLOW BACK AROUND TO THE NORTH AND INCREASING THE SWELLS ONCE AGAIN.
WILL POST AN SCA FOR ALL THE LOWER TX MARINE LOCATIONS THROUGH THIS
EVENING WITH SCA CONDITIONS LIMITED TO THE OFFSHORE WATERS LATER
TONIGHT. EXPECTED PRETTY ROUGH MARINE CONDITIONS TO PREVAIL FOR THE
BULK OF THIS COMING CWF ISSUANCE. WNA WIND AND SWELL GUIDANCE LOOKS
REASONABLE.
&&

.FIRE WEATHER...AFTER LOOKING AT PROGGED LOW LEVEL WINDS AND
EXPECTED RH VALUES AROUND THE REGION TODAY IN THE WAKE OF THE
FROPA...WILL UPGRADE THE FIRE WEATHER WATCH TO A RED FLAG WARNING
FOR THE ENTIRE BRO CWA.  WILL UPDATED THE RFW HERE SHORTLY.
&&

.AVIATION...THE COLD FRONT HAS PUSHED INTO WEST TX EARLY THIS
MORNING ON ITS WAY TOWARDS THE LOWER RGV. THE LIGHT SE SURFACE WINDS
COMBINED WITH FAIRLY NARROW TEMP/DEWPOINT SPREADS WILL SET THE STAGE
FOR LOW CLDS AND VSBYS DURING THE EARLY MORNING. THIS WILL BE SHORT
LIVED HOWEVER AS BOTH THE MET AND GFS SHOW THE SURFACE FLOW SHIFTING
AROUND TO A DRIER W-NW DIRECTION A LITTLE AFTER SUNRISE TODAY. THIS
WILL DRAMATICALLY IMPROVE THE VSBYS AND CEILINGS THROUGH THE REST OF
THIS CURRENT TAF PERIOD WITH THE NORTHERLY SURFACE FLOW SLACKENING
LATER TODAY AND TONIGHT. GENERAL IFR/LIFR CONDITIONS WILL PREVAIL
INITIALLY THEN SHIFTING BACK TO VFR CONDITIONS AFTER SUNRISE.
&&

.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL  73  44  70  57 /  20  10  10  10
BROWNSVILLE          77  44  70  58 /  20  10  10  10
HARLINGEN            76  39  72  54 /  20  10  10  10
MCALLEN              73  43  72  54 /  20  10  10  10
RIO GRANDE CITY      73  46  71  51 /  10  10  10  10
SOUTH PADRE ISLAND   72  54  69  54 /  20  10  10  10

&&

.BRO WATCHES/WARNINGS/ADVISORIES...RED FLAG WARNING FROM 9 AM THIS
MORNING TO 7 PM CST THIS EVENING FOR TXZ248>257. SMALL CRAFT
ADVISORY FROM 9 AM THIS MORNING TO 7 PM CST THIS EVENING FOR
GMZ130-132-135. SMALL CRAFT ADVISORY FROM 9 AM THIS MORNING TO 3 AM
CST FRIDAY FOR GMZ150-155-170-175.

&&

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

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HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE BROWNSVILLE TX
630 AM CST WED JAN 30 2008

TXZ248>257-311200-
ZAPATA-JIM HOGG-BROOKS-KENEDY-STARR-HIDALGO-INLAND WILLACY-
INLAND CAMERON-COASTAL WILLACY-COASTAL CAMERON-
630 AM CST WED JAN 30 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR DEEP SOUTH TEXAS.

.DAY ONE...TONIGHT.

AREAS OF FOG...SOME POSSIBLY LOCALLY DENSE...WILL DEVELOP AFTER
MIDNIGHT OVER DEEP SOUTH TEXAS. AND...THERE IS A MODERATE RISK OF
RIP CURRENTS AT THE BEACHES OF SOUTH PADRE ISLAND AND BOCA CHICA.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

AREAS OF FOG WILL PERSIST OVER PORTIONS OF DEEP SOUTH TEXAS UNTIL
SHORTLY AFTER SUNRISE THURSDAY MORNING. A SMALL CRAFT ADVISORY OR
GALE WARNING WILL BE NEEDED ALONG THE LOWER TEXAS COAST THURSDAY
THROUGH EARLY FRIDAY MORNING AS WINDS AND SEAS INCREASE IN THE WAKE
OF A COLD FRONT. AND...A MODERATE TO HIGH RISK OF RIP CURRENTS IS
EXPECTED THROUGH MUCH OF THE FORECAST PERIOD.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTER ACTIVATION IS NOT EXPECTED.

TOMASELLI