429
FXUS64 KBRO 262328 AAA
AFDBRO
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BROWNSVILLE TX
528 PM CST FRI DEC 26 2025
..NEW AVIATION
KEY MESSAGES
UPDATED AT 525 PM CST FRI DEC 26 2025
* UNSEASONABLY WARM, NEAR RECORD-BREAKING TEMPERATURES ARE EXPECTED
TO CONTINUE TODAY THROUGH SUNDAY.
* A STRONG COLD FRONT WILL BRING WINDY CONDITIONS ALONG WITH
MARKEDLY COOLER AND DRIER WEATHER TO THE REGION ON MONDAY.
* STRONG NORTHERLY WINDS 20-35 MPH WITH HIGHER GUSTS ON SUNDAY NIGHT
AND ESPECIALLY ON MONDAY WILL PROMPT MULTIPLE MARINE/COASTAL
HAZARDS SUNDAY NIGHT THROUGH TUESDAY.
* SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE SUNDAY NIGHT INTO
MONDAY NIGHT ALONG/AHEAD OF THE COLD FRONT. RIGHT NOW, WE HAVE LOW
TO MEDIUM (30-60%) CHANCES SUNDAY NIGHT AND MONDAY.
* THE COMBINATION OF ANTECEDENT DRY SOILS, A MUCH DRIER AIRMASS,
AND BLUSTERY NORTHERLY WINDS COULD DRIVE UP SOME FIRE WEATHER
CONCERNS ON MONDAY AND TUESDAY. AREAS ALONG AND WEST OF IH-69C
AT RISK.
DISCUSSION
ISSUED AT 154 PM CST FRI DEC 26 2025
A PROGRESSIVE/CHANGEABLE WEATHER PATTERN IS EXPECTED TO DEVELOP
AND TAKE PLACE DURING THE FORECASTER PERIOD OR THROUGH NEXT
FRIDAY. THROUGH SUNDAY, THE WEATHER PATTERN ACROSS DEEP SOUTH
TEXAS AND THE RIO GRANDE VALLEY WILL REMAIN STATUS QUO (THAT IS
RAIN-FREE WITH WARMER THAN NORMAL TEMPERATURES PERSISTING).
HOWEVER, SIGNIFICANT CHANGES TO THE COOL SIDE ARE EXPECTED TO TAKE
PLACE SUNDAY NIGHT THROUGH MONDAY AS A STRONG MODIFIED ARCTIC
(CAK) AIRMASS (I.E. 1030-1045 MB SFC HIGH PRESSURE SYSTEM) BUILDS
INTO THE REGION FOLLOWING A STRONG COLD FROPA. SCATTERED SHOWERS
WILL LIKELY BE ASSOCIATED WITH THE COLD FRONT SUNDAY NIGHT AND
ESPECIALLY ON MONDAY.
MULTIPLE HAZARDS INCLUDING COASTAL/MARINE (SEE MARINE SECTION FOR
MORE DETAILS) AND MAYBE EVEN FIRE WEATHER (SEE FIRE WEATHER
SECTION FOR MORE DETAILS) ARE POSSIBLE IN ASSOCIATION WITH THIS
COLD FRONT EARLY NEXT WEEK. COLD AIR ADVECTION (CAA) REGIME
REMAINS IN PLACE THROUGH TUESDAY NIGHT BEFORE TEMPERATURES BEGIN
TO MODERATE THEREAFTER.
TODAY THROUGH SUNDAY: WARM AIR ADVECTION (WAA) AMID SOUTHERLY WINDS
UNDERNEATH A 585 MB SFC HEAT RIDGE WILL CONTINUE TO FOSTER NEAR
RECORD-BREAKING TEMPERATURES TODAY THROUGH SUNDAY (SEE CLIMATE
SECTION FOR MORE DETAILS). DAYTIME HIGH TEMPERATURES TODAY THROUGH
SUNDAY ARE PROGGED TO CLIMB INTO THE MID 80S TO NEAR 90F DEGREES,
SOME 10-15F DEGREES ABOVE NORMAL. TONIGHT AND SATURDAY NIGHT WILL
CONTINUE MILD WITH OVERNIGHT LOW TEMPERATURES IN THE 60S ACROSS THE
REGION. DRY/RAIN-FREE WEATHER WILL PERSIST THROUGH SUNDAY AS THE
AFOREMENTIONED RIDGE AND ASSOCIATED 1015 MS SFC HIGH PRESSURE SYSTEM
REMAINS ANCHORED OVER THE REGION.
SUNDAY NIGHT THROUGH MONDAY: SIGNIFICANT WEATHER CHANGES THAT
INCLUDES A SHARP COOL DOWN ALONG WITH THE POTENTIAL FOR MULTIPLE
WEATHER HAZARDS LOOM SUNDAY NIGHT AND ESPECIALLY DURING THE DAY ON
MONDAY. FORECAST MODELS AND ENSEMBLES CONTINUE TO DEPICT STRONG
COLD FRONT (I.E. NOTICEABLE 3 HR MSL PRESSURE CHANGES AND
ISALLOBARIC WINDS SEEN) PUSHING THROUGH SOUTH TEXAS SUNDAY NIGHT.
STRONG SFC CONVERGENCE AHEAD OF THE COLD FRONT WILL LEAD TO THE
DEVELOPMENT OF SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING FORM
NORTH TO SOUTH SUNDAY NIGHT AND ESPECIALLY DURING THE DAY ON
MONDAY. CURRENTLY, WE HAVE LOW TO MEDIUM (30-60%) CHANCES FOR
SHOWERS/THUNDERSTORMS TO DEVELOP SUNDAY NIGHT AND MONDAY WITH THE
BEST CHANCES BEING ALONG THE VALLEY AND SPECIFICALLY OVER CAMERON
COUNTY.
FOLLOWING THE COLD FROPA, STRONG COLD AIR ADVECTION (CAA) AMID
STRONG NORTHERLY WINDS WILL RESULT IN FALLING TEMPERATURES DURING
THE DAY AND A SMALL DIURNAL RANGE IN TEMPERATURES BETWEEN SUNDAY
NIGHT AND MONDAY. DAYTIME HIGHS ON MONDAY WILL BE COOLER THAN
NORMAL LEVELS WITH VALUES STRUGGLING TO MAKE IT OUT OF THE 50S
MOST PLACES AND 60S OVER CAMERON COUNTY AND ALONG/NEAR THE LOWER
TEXAS COAST.
WITH A MODIFIED ARCTIC AIRMASS FEATURING A 1030 MB SFC HIGH
BEHIND THE COLD FROPA, AN ENHANCED THERMAL AND PRESSURE GRADIENT
WILL RESULT IN STRONG NORTHERLY WINDS 20-35 MPH WITH HIGHER GUSTS
ON MONDAY WILL RESULT IN HAZARDOUS COASTAL/MARINE CONDITIONS
DEVELOPING (SEE MARINE SECTION FOR MORE DETAILS). THAT SAID,
EXPECT FOR MONDAY TO BE WINDY WITH FALLING TEMPERATURES AND THE
CHANCE FOR SHOWERS AND THUNDERSTORMS.
MONDAY NIGHT THROUGH TUESDAY NIGHT, A FULL COLD AIR ADVECTION
(CAA) REGIME WILL BE IN PLACE OVER DEEP SOUTH TEXAS AND THE RIO
GRANDE VALLEY. DECIDED TO USE A BLEND OF SOME OF THE COLDER MODELS
TO KNOCK TEMPERATURES DOWN A FEW DEGREES DURING THIS TIME PERIOD
AS MANY GLOBAL FORECAST MODELS (WARMER BIASES) STRUGGLE TO
CAPTURE THESE SHALLOW COLD AIR EVENTS. FOR NOW, OVERNIGHT LOWS
MONDAY NIGHT WILL BE IN THE 40S MOST PLACES. TUESDAY NIGHT,
OVERNIGHT LOWS WILL BE IN THE 30S MOST PLACES.
WEDNESDAY THROUGH FRIDAY OF NEXT WEEK, TEMPERATURES LOOK TO REBOUND
AMID A RETURN FLOW DEVELOPING OUT OF THE SOUTH. DRY /RAIN-FREE
WEATHER WILL PREVAIL DURING THIS TIMEFRAME.
AVIATION
(00Z TAFS)
ISSUED AT 525 PM CST FRI DEC 26 2025
VFR CONDITIONS ARE EXPECTED TO GIVE WAY TO MVFR CEILINGS AND
POTENTIALLY REDUCED VISIBILITY WITH PATCHY FOG AND SHALLOW FOG
LATE TONIGHT. CONDITIONS IMPROVE BY MID SATURDAY MORNING WITH VFR
CONDITIONS THROUGH SATURDAY AFTERNOON.
MARINE
ISSUED AT 154 PM CST FRI DEC 26 2025
LIGHT TO MODERATE SOUTHERLY WINDS AND MODERATE SEAS WILL PREVAIL
THROUGH SUNDAY. SUNDAY NIGHT INTO MONDAY, MARINE CONDITIONS ARE
EXPECTED TO RAPIDLY DETERIORATE AS A STRONG FRONT WITH AN ENHANCED
PRESSURE GRADIENT SWEEPS THROUGH THE REGION. STRONG NORTHERLY
WINDS 20-30 KTS WITH HIGHER GUSTS WILL RESULT IN DANGEROUS SEAS
DEVELOPING BEGINNING SUNDAY NIGHT AND PERSISTING THROUGH MONDAY. A
SMALL CRAFT ADVISORY (SCA) AND MAYBE EVEN A GALE WATCH WILL BE
NEEDED DURING THIS TIME PERIOD (SUNDAY NIGHT THROUGH MONDAY,
POSSIBLY PERSISTING THROUGH TUESDAY DUE TO THE WAVE HEIGHTS).
SCATTERED SHOWERS AND THUNDERSTORMS WILL ALSO BE POSSIBLE SUNDAY
NIGHT INTO MONDAY, COURTESY OF INCREASED INSTABILITY/FORCING FROM
THE STRONG COLD FROPA. TUESDAY EVENING/NIGHT SEAS ARE EXPECTED TO
IMPROVE. WEDNESDAY THROUGH FRIDAY, MARINE CONDITIONS WILL BECOME
FAVORABLE AGAIN WITH LOW TO MODERATE WINDS AND SEAS.
FIRE WEATHER
ISSUED AT 154 PM CST FRI DEC 26 2025
BEHIND THE COLD FROPA EARLY MONDAY, DRASTICALLY COOLER AND DRIER
WEATHER CONDITIONS ARE EXPECTED TO SPREAD ACROSS THE REGION. WILL
NEED TO MONITOR THE RISK FOR WILDFIRE THREAT ON MONDAY AND TUESDAY
DUE TO THE COMBINATION OF DRY ANTECEDENT SOILS, AND MUCH DRIER
AIRMASS INCOMING, AND BREEZY NORTHERLY WINDS. BRUSH COUNTRY (I.E.
ZAPATA, JIM HOGG, BROOKS, AND STARR COUNTIES) ARE AREAS IN
PARTICULAR THAT WE'LL BE MONITORING. MINIMUM RELATIVE HUMIDITY
(RH) VALUES ARE EXPECTED TO DROP INTO THE MID 20S TO UPPER TEENS
WEST OF IH-69C ON MONDAY. ON TUESDAY, MINIMUM RELATIVE HUMIDITY
(RH) VALUES ARE EXPECTED TO FALL INTO THE MID 20S TO MID-UPPER
TEENS ALONG AND WEST OF IH-69E WITH RH VALUES IN THE TEENS ALONG
AND WEST OF IH-69C. WIND TRENDS WILL BE CRUCIAL. MONDAY LOOKS TO
BE THE BREEZIER DAY WITH WINDS WANING BY TUESDAY. A FIRE DANGER
STATEMENT (RFD) MAY BE NEEDED ON MONDAY DUE TO THE POTENTIAL FOR
ELEVATED FIRE WEATHER CONDITIONS.
CLIMATE
ISSUED AT 154 PM CST FRI DEC 26 2025
AN ANOMALOUSLY STRONG 585 MB SFC HEAT RIDGE OVER THE REGION WILL
RESULT IN UNSEASONABLY WARM, NEAR RECORD-BREAKING TEMPERATURES
CONTINUING TODAY THROUGH SUNDAY. TEMPERATURE ANOMALIES ARE
EXPECTED TO BE ON THE ORDER OF 10-15F+ DEGREES ABOVE AVERAGE
THROUGH SUNDAY.
BROWNSVILLE RECORD HIGHS
FRIDAY, DECEMBER 26, 2025....85/2024
SATURDAY, DECEMBER 27, 2025....87/1968
SUNDAY, DECEMBER 28, 2025....90/2024
HARLINGEN RECORD HIGHS
FRIDAY, DECEMBER 26, 2025....89/1964
SATURDAY, DECEMBER 27, 2025....87/2008, 1950
SUNDAY, DECEMBER 28, 2025....92/1968
MCALLEN RECORD HIGHS
FRIDAY, DECEMBER 26, 2025....89/2024, 2015
SATURDAY, DECEMBER 27, 2025....94/1968
SUNDAY, DECEMBER 28, 2025....91/2024
PRELIMINARY POINT TEMPS/POPS
BROWNSVILLE 69 84 68 85 / 0 0 0 0
HARLINGEN 66 86 65 87 / 0 0 0 0
MCALLEN 70 87 69 90 / 0 0 0 0
RIO GRANDE CITY 66 89 66 90 / 0 0 0 0
SOUTH PADRE ISLAND 70 77 71 78 / 0 0 0 0
BAYVIEW/PORT ISABEL 67 82 67 83 / 0 0 0 0
BRO WATCHES/WARNINGS/ADVISORIES
TX...NONE.
GM...NONE.
SHORT TERM...23-EVBUOMA
LONG TERM....23-EVBUOMA
AVIATION...56-HALLMAN
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