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000
FXUS64 KBRO 011134 AAA
AFDBRO

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BROWNSVILLE TX
534 AM CST SUN FEB 1 2015

.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

&&

.AVIATION...A FEW HIGH BASED SHOWERS ARE NOTED ON RADAR AND ARE
ANTICIPATED TO PASS TO THE NORTHEAST SHORTLY AFTER SUNRISE.
MAINLY VFR CEILINGS ARE EXPECTED TODAY WITH LOWERING CEILINGS AND
ANOTHER ROUND OF SHOWERS AND LOW CHANCE FOR THUNDERSTORMS TONIGHT
IN ADVANCE OF A STRONG COLD FRONT. PRIOR TO THE FRONT WINDS NEARLY
GO CALM AND PATCHY DENSE FOG AND IFR CIGS AND VSBYS ARE POSSIBLE
AND ARE MENTIONED IN TEMPO GROUPS AT KBRO AND KHRL. STRONG COLD
FRONT SURGES THROUGH THE TAF SITES AFTER MIDNIGHT WITH THE
SURFACE PRESSURE GRADIENT STRENGTHENING THROUGH THE NIGHT. WINDS
TO GUSTS NEAR 30 KNOTS AT THE TERMINAL SITES AFTER MIDNIGHT
THROUGH SUNRISE MONDAY.

&&

.PREV DISCUSSION... /ISSUED 413 AM CST SUN FEB 1 2015/

SHORT TERM /NOW THROUGH MONDAY/...

IMPACTS... ANOTHER ROUND OF SHOWERS AND A RUMBLE OF THUNDER TONIGHT
FOLLOWED BY A STRONG SHARP COLD FRONT WITH SIGNIFICANT MARINE
IMPACTS.

RELEVANT FEATURES... CLOSED UPPER LOW OVER NW MEXICO WITH STRONG
SUBTROPICAL JET. A SHARP SHORTWAVE TROUGH DIVING THROUGH THE CENTRAL
ROCKIES WITH A STRONG COLD FRONT CURRENTLY OVER MOVING INTO THE
OKLAHOMA AND TEXAS PANHANDLE

TODAY... SOUTH TO SOUTHWEST FLOW FROM THE SURFACE TO 850MB AND SW-W
850-700MB TO SIGNIFICANTLY WARM THE ATMOSPHERE WITH STRONG INVERSION
AT 850MB. THIS WARMING AND CAP SHOULD SQUASH ANY CHANCE OF SHOWERS
TODAY. SURFACE TEMPERATURES WARM UP AS WELL WITH DOWNSLOPING AND
COMPRESSION IN ADVANCE OF TONIGHT`S COLD FRONT. MODELS AND GOING
FORECAST CONTINUE TO INDICATE UPPER 70S TO LOWER 80S. IF MORE SUN
BREAKS THROUGH THE MID TO HIGHER LEVEL CLOUDS IN RESPONSE TO THE
SUBTROPICAL JET TEMPERATURES COULD EXCEED EXPECTED HIGHS BY 2 TO 4
DEGREES. SURFACE WINDS WILL BE MUCH LIGHTER WITH SURFACE LOW
DEVELOPING IN THE VICINITY OF UPPER VALLEY.

SUNDAY NIGHT AND MONDAY... MODEL ARE IN SIMILAR AGREEMENT WITH THE
PASSAGE OF THE COLD FRONT AFTER MIDNIGHT. PREFRONTAL TROUGH TO HELP
SLACKEN WINDS NEAR CALM WITH SOME FOG PRODUCTION PRIOR TO FRONTAL
PASSAGE. STRONG UPPER JET TRACKS OVER THE REGION PRODUCING SPEED
DIVERGENCE COMBINING WITH A WEAKENING AND CAP AS THE FRONT
APPROACHES. ANOTHER ROUND OF CONVECTION TO DEVELOP IN ADVANCE OF THE
FRONT AND LATEST FORECAST MAINTAINS THE CHANCE OF RAIN WITH SOME
ISOLATED THUNDER. FRONT BARRELS THROUGH THE CWA AND GRADIENT
STRENGTHENS THROUGH THE NIGHT. 25-35KT 925-850MB JET TO MIX TO THE
SURFACE WITH STRONGEST NORTH TO NORTHEAST WINDS AROUND DAYBREAK.
WINDS ADVISORY WIND SPEEDS ARE NOT OUT OF THE QUESTION FOR A FEW
HOURS ALONG THE IMMEDIATE COAST WITH WINDY CONDITIONS INLAND.
TEMPERATURES BEGIN TO FALL AFTER THE FRONTAL PASSAGE BUT THE MORE
WITH SIGNIFICANT FALLING TEMPERATURES ARE DELAYED UNTIL THE STRONGER
WIND GRADIENT DEVELOPS UNTIL AFTER 3 AM. BOTH GFS AND NAM
TEMPERATURE GUIDANCE SHOWS TEMPERATURES FALLING THROUGH MONDAY
MORNING WITH A SLIGHT RECOVERY IN THE AFTERNOON. MAX TEMPS ARE
LIKELY AROUND MIDNIGHT WITH TEMPERATURES BOTTOMING OUT IN THE MID TO
UPPER 40S MID MORNING THEN RECOVERING INTO THE LOWER TO MID 50S
MONDAY AFTERNOON. MUCH DRIER AIR WORKS IN BEHIND THE FRONT LATER
MONDAY WITH LOW LEVEL MOISTURE BEING SHUNTED SOUTH OF THE BORDER.
HIGHER CLOUDS TO MAINTAIN A THICKER VEIL OF CLOUDS DUE TO THE UPPER
TROUGH OVER NORTH CENTRAL MEXICO.

LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...GFS/ECMWF IN GOOD
AGREEMENT ON POSITIONING OF UPPER LEVEL LOW TO OUR SOUTHWEST TO
BEGIN THE LONG TERM PERIOD. HOWEVER THERE ARE SOME DISAGREEMENT ON
OVERALL SPEED ACROSS NORTHERN MEXICO INTO CENTRAL TEXAS TUESDAY
INTO WEDNESDAY. GFS HAS NOW BECOME THE SLOWER SOLUTION WITH THE
ECMWF MORE CONSISTENT THE PAST FEW RUNS. THE GFS HOLDS ON TO
PRECIPITATION LONGER WHICH LASTS INTO WEDNESDAY AFTERNOON AND INTO
THE COASTAL WATERS WEDNESDAY NIGHT. THE ECMWF ENDS PRECIPITATION
OVER THE LAND AREAS BY MIDDAY WEDNESDAY. HAVE LEANED POPS DURING
THIS TIMEFRAME OVER TO THE ECMWF WITH A SLIGHT LEAN OVER TO THE
GFS WEDNESDAY AFTERNOON. TEMPERATURES ON WEDNESDAY WILL ALSO BE A
CHALLENGE...IF CLOUDS HOLD IN LONGER MAY NOT REACH UPPER 60S FOR
HIGHS. A COLD FRONT WILL SWEEP THROUGH THURSDAY WITH FRESH HIGH
PRESSURE ARRIVING IN ITS WAKE. DRY CONDITIONS RETURN THURSDAY
THROUGH SUNDAY. HIGHS WILL BE SLIGHTLY COOLER FOR FRIDAY IN THE
LOWER 60S BUT AS HIGH PRESSURE MOVES EAST AND SOUTHEAST WINDS
RETURN BY SATURDAY LATE MORNING...A WARMING TREND WILL ENSUE WITH
HIGHS IN THE MID 70S BY NEXT SUNDAY.

MARINE...NOW THROUGH SUNDAY NIGHT...PRESSURE GRADIENT WEAKENS
TODAY WITH A LIGHT TO MODERATE SOUTHEAST TO SOUTH WIND AND
LOWERING SEAS. THE STRONG COLD FRONT SURGES THROUGH THE COASTAL
WATERS AFTER MIDNIGHT WITH GALE WARNINGS POSTED FOR THE GULF
WATERS FROM MIDNIGHT TONIGHT THROUGH 9 AM MONDAY WITH SMALL CRAFT
ADVISORIES LIKELY TO FOLLOW THE GALE WARNING. FOR THE LAGUNA
STRONGEST EXPECTED WIND GUSTS JUST SHY OF GALES WITH SMALL CRAFT
ADVISORY CONDITIONS A GOOD BET FROM MIDNIGHT TONIGHT THROUGH AT
LEAST NOON MONDAY.

MONDAY NIGHT THROUGH THURSDAY... A COASTAL LOW/TROUGH WILL DEVELOP
ACROSS THE WESTERN GULF OF MEXICO ON TUESDAY IN RESPONSE TO
INBOUND UPPER LOW WITH OFFSHORE WINDS VEERING MORE TO THE EAST.
UNSETTLED WEATHER WILL HANG ON THROUGH WEDNESDAY DUE TO THE
PROXIMITY OF THE OFFSHORE LOW...BUT THE STRONGEST WINDS AND
HIGHEST SEAS ASSOCIATED WITH THE LOW WILL REMAIN JUST BEYOND THE
LOCALLY FORECASTED MARINE ZONES. THE COASTAL LOW PULLS OUT
WEDNESDAY AND ANOTHER COLD FRONT ARRIVES THURSDAY WITH WINDS IN
THE COASTAL WATERS INCREASING TO SMALL CRAFT ADVISORIES THURSDAY
AFTERNOON.

&&

.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL  77  54  54  50 /  10  40  20  20
BROWNSVILLE          80  55  55  49 /  10  40  20  20
HARLINGEN            81  53  56  48 /  10  40  20  20
MCALLEN              83  53  57  49 /  10  40  20  30
RIO GRANDE CITY      83  52  58  46 /  10  30  20  30
SOUTH PADRE ISLAND  MMM MMM MMM MMM / MMM MMM MMM MMM

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY FOR WINDS FROM MIDNIGHT TONIGHT TO NOON CST
     MONDAY FOR GMZ130-132-135.

     GALE WARNING FROM MIDNIGHT TONIGHT TO 9 AM CST MONDAY FOR GMZ150-
     155-170-175.

&&

$$

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