462
FXUS64 KBRO 160556 AAA
AFDBRO
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BROWNSVILLE TX
1256 AM CDT MON MAR 16 2026
..NEW AVIATION
KEY MESSAGES
UPDATED AT 1243 AM CDT MON MAR 16 2026
KEY MESSAGES:
* STRONG COLD FRONT (MODIFIED ARCTIC AIRMASS) ARRIVES TONIGHT;
TEMPERATURES BY MONDAY MORNING WILL HAVE PLUMMETED 40-50F DEGREES
FROM SUNDAY AFTERNOON'S HIGHS.
* STRONG TO POTENTIALLY DAMAGING WINDS DEVELOP TONIGHT INTO MONDAY;
NORTHERLY WINDS 25-35 MPH ARE EXPECTED TO GUST AS HIGH AS 45-55
MPH WITH LOCAL GUSTS AS HIGH AS 55-60 MPH.
* A RED FLAG WARNING (RFW) FOR A CRITICAL FIRE WEATHER RISK IS IN
EFFECT FOR ALL OF DEEP SOUTH TEXAS, EXCLUDING THE ISLAND TILL 7 PM
CDT MONDAY; FIRE DANGER RANGES BETWEEN VERY HIGH AND EXTREME.
* HAZARDOUS MARINE/COASTAL CONDITIONS LIKELY THOUGH MONDAY; A GALE
WARNING IS IN EFFECT FOR THE LAGUNA MADRE AND GULF WATERS TILL 7
PM CDT MONDAY.
DISCUSSION
ISSUED AT 1047 PM CDT SUN MAR 15 2026
AFTER TODAY'S HEAT SPIKE, WHICH RESULTED IN MCALLEN TYING IT'S
RECORD HIGH OF 103F SET BACK IN 2008, COURTESY OF STRONG
COMPRESSIONAL HEATING FROM A NEARBY DRYLINE AND STRONG SOUTHERLY
WINDS, A SIGNIFICANT CHANGE TO THE WEATHER PATTERN IS JUST ABOUT
UNDERWAY FOR ALL OF DEEP SOUTH TEXAS AND THE RIO GRANDE VALLEY.
DRIVEN BY AN ANOMALOUSLY STRONG AND EMERGING 591-591 DAM SONORAN
HEAT RIDGE OVER THE SOUTHWESTERN U.S. AND A MATURE (NEUTRALLY-
TILTED) POWERHOUSE MID-LATITUDE CYCLONE OVER THE MIDWEST/GREAT
LAKES REGION, THAT'S PRODUCING COMBINATION OF BLIZZARD CONDITIONS
IN IT'S COLD SECTOR AND SEVERE WEATHER IN IT'S WARM SECTOR, A VERY
STRONG COLD FRONT (MODIFIED ARCTIC FRONT) WILL SWEEP THROUGH ALL
OF DEEP SOUTH TEXAS AND THE RIO GRANDE VALLEY TONIGHT.
ACCOMPANYING THIS COLD FRONT WILL BE A 40-50F DEGREE DROP OFF IN
TEMPERATURES FROM THIS AFTERNOON TO MONDAY MORNING ALONG WITH STRONG
TO DAMAGING NORTHERLY WINDS 25-35 MPH GUSTING AS HIGH AS 45-55 MPH
LATE TONIGHT INTO MONDAY. THERE COULD BE AN ISOLATED CASE WHERE WIND
GUSTS REACH 55-60 MPH. MULTIPLE HAZARDS, INCLUDING FIRE WEATHER
AND COASTAL/MARINE ARE IN EFFECT THROUGH THE DAY ON MONDAY IN
RESPONSE TO THE ARCTIC FRONT AND IMPENDING WEATHER CHANGES.
LATEST RADAR SCANS AND SFC ANALYSIS SHOWS THE COLD FRONT QUICKLY
ADVANCING SOUTHWARD OVER CORPUS CHRISTI'S COUNTY WARNING AREA (CWA)
AND KNOCKING ON THE DOORS OF THE NORTHERN RANCHLANDS. EXPECT FOR
THIS COLD FRONT TO PUSH THROUGH DEEP SOUTH TEXAS FROM NORTH TO SOUTH
BETWEEN MIDNIGHT AND 4AM. ALONG AND BEHIND THE COLD FROPA, AN
ENHANCED PRESSURE AND THERMAL (ISOLLABARIC) GRADIENT WILL RESULT
IN STRONG TO AT TIMES DAMAGING WINDS. NORTH-NORTHEAST WINDS 25-35
MPH ARE EXPECTED TO GUSTS AS HIGH AS 45-55 MPH WITH ISOLATED
GUSTS UP TO 60 MPH. ISOLATED POWER OUTAGES ARE POSSIBLE, SO BE
PREPARED. A WIND ADVISORY REMAINS IN EFFECT FOR ALL OF DEEP SOUTH
TEXAS TILL 8 AM CDT AND FOR BROOKS, KENEDY, HIDALGO, WILLACY, AND
CAMERON COUNTIES TILL 1 PM CDT MONDAY.
THROUGH TONIGHT, FOLLOWING THE COLD FROPA, TEMPERATURES WILL PLUMMET
AS THESE WINDS WILL USHER IN A MODIFIED ARCTIC AIRMASS INTO THE
REGION. BY MONDAY MORNING, WAKE UP TEMPERATURES WILL BE IN THE UPPER
40S ACROSS PARTS OF THE NORTHERN RANCHLANDS TO THE MID 50S ALONG THE
RIO GRANDE VALLEY. AMID ADDITIONAL COOL AIR ADVECTION (CAA) AND THE
MODIFIED ARCTIC AIRMASS STILL BUILDING INTO THE REGION, MONDAY WILL
FEATURE THE COOLEST DAY OF THE WEEK WITH DAYTIME HIGHS STRUGGLING TO
MAKE IT OUT OF THE 60S, SOME 30-40F DEGREES COOLER THAN THE HIGHS ON
SUNDAY, AND ~15F DEGREES COOLER THAN NORMAL. WITH THE COOL AIRMASS
FULLY LOCKED IN OVER THE REGION ON TOP OR SUFFICIENT RADIATIONAL
COOLING ON CLEARING SKIES, A COLD NIGHT LOOMS MONDAY NIGHT WITH
OVERNIGHT LOWS MAINLY IN THE 40S WITH 50S FOUND ALONG/NEAR THE
COAST.
LOW RELATIVE HUMIDITY (RH) VALUES AND WINDY CONDITIONS ON TOP OF AN
ONGOING DROUGHT WILL RESULT IN CRITICAL FIRE WEATHER RISK WITH THE
POTENTIAL FOR FUELS BECOMING COMBUSTIBLE UPON FIRE IGNITION ON
MONDAY ACROSS DEEP SOUTH TEXAS. A RED FLAG WARNING (RFW) REMAINS IN
EFFECT FOR ALL OF DEEP SOUTH TEXAS, EXCLUDING THE ISLAND FROM 10 PM
CDT TONIGHT TO 7 PM MONDAY (SEE FIRE WEATHER SECTION FOR MORE
DETAILS). THESE STRONG WINDS WILL ALSO CREATE HAZARDOUS MARINE AND
COASTAL CONDITIONS TONIGHT THROUGH MONDAY (SEE MARINE SECTION FOR
MORE DETAILS).
BEYOND MONDAY NIGHT, A WARMING TREND IS EXPECTED TO TAKE PLACE
THROUGH THE REMAINDER OF THE FORECAST PERIOD. BY THURSDAY,
TEMPERATURES ARE EXPECTED TO RETURN TO UNSEASONABLE WARM LEVELS
(80S/90S) ACROSS DEEP SOUTH TEXAS AND THE RIO GRANDE VALLEY.
AVIATION
(06Z TAFS)
ISSUED AT 1243 AM CDT MON MAR 16 2026
A STRONG COLD FRONT WILL ARRIVE IN THE NEXT COUPLE OF HOURS. THE
MAIN CONCERN FOR TERMINALS WILL BE THE STRONG NORTHERLY WINDS THAT
DEVELOP IN THE WAKE OF THE FRONT. FROPA IS EXPECTED AROUND 0630Z
AT HRL/MFE AND 0730Z AT BRO. WINDS WILL SHIFT TO THE NORTH BEHIND
THE FRONT AND BECOME STRONG WITH WIND SPEEDS BETWEEN 15-25 KTS
WITH GUSTS 35-40 KNOTS. A FEW GUSTS AS HIGH AS 50 KTS WILL BE
POSSIBLE LATER THIS MORNING INTO THE AFTERNOON. WINDS ARE EXPECTED
TO DECREASE AND BECOME MODERATE BETWEEN 10 TO 15 KNOTS LATER THIS
EVENING. BRIEF MVFR CONDITIONS WILL BE POSSIBLE AHEAD AND ALONG
THE FRONTAL BOUNDARY. OTHERWISE, VFR CONDITIONS ARE EXPECTED FOR
THE NEXT 24 HOURS.
MARINE
ISSUED AT 1047 PM CDT SUN MAR 15 2026
A GALE WARNING IS IN EFFECT FOR THE LAGUNA MADRE AND GULF WATERS
TILL 7 PM CDT MONDAY. NORTH-NORTHEAST WINDS 25-35 KNOTS GUSTING UP
TO 40 KNOTS OR SO IS EXPECTED. THIS WILL DRIVE UP HIGH SEAS WITH
WAVE HEIGHTS RANGING BETWEEN 13-18 FEET. MONDAY NIGHT THROUGH
TUESDAY, MARINE CONDITIONS (SEAS) WILL IMPROVE IN RESPONSE TO THE
RETURN OF LIGHTER WINDS. BY WEDNESDAY, FAVORABLE MARINE CONDITIONS
ARE EXPECTED TO RETURN WITH LOW TO MODERATE WINDS AND SEAS.
FAVORABLE MARINE CONDITIONS WILL PREVAIL THROUGH THE REMAINDER OF
THE FORECAST PERIOD.
FIRE WEATHER
ISSUED AT 1047 PM CDT SUN MAR 15 2026
A RED FLAG WARNING (RFW) IS IN EFFECT FOR ALL OF DEEP SOUTH TEXAS,
EXCLUDING THE ISLAND TILL 7 PM CDT MONDAY. THE COMBINATION OF LOW
RELATIVE HUMIDITY (RH) VALUES, WINDY CONDITIONS, AND AN ONGOING
DROUGHT RANGING FROM D2 SEVERE TO D4 EXCEPTIONAL, WILL RESULT IN
CRITICAL FIRE WEATHER RISK ON MONDAY. ANY FIRES THAT IGNITE UNDER
THESE CONDITIONS WILL HAVE THE POTENTIAL TO BECOME COMBUSTIBLE AND
RATHER AGGRESSIVE. WE CONTINUE TO URGED EVERYONE TO NOT BURN ON
MONDAY AND CONTINUE TO EXERCISE SAFE FIRE WEATHER CONDITIONS.
THE TEXAS A&M FOREST SERVICE HAS OUTLOOKED THE REGION UNDER A
VERY HIGH TO EXTREME FIRE DANGER FOR MONDAY. ENERGY RELEASE
COMPONENT (ERC) VALUES WILL BE HIGH ACROSS THE REGION ON MONDAY
RANGING BETWEEN 75- 100%. FINALLY, FUELS WILL BE DRY TO CRITICALLY
DRY ON MONDAY.
ADDITIONAL FIRE WEATHER CONCERNS ARE POSSIBLE THROUGH NEXT WEEKEND
DUE TO A CONTINUATION OF AT TIMES LOW RELATIVE HUMIDITY LEVELS AND
BREEZY CONDITIONS, IN ADDITION TO AN ONGOING DROUGHT.
PRELIMINARY POINT TEMPS/POPS
BROWNSVILLE 66 53 71 57 / 10 10 10 0
HARLINGEN 68 48 73 52 / 10 10 10 0
MCALLEN 71 50 76 55 / 0 10 10 0
RIO GRANDE CITY 70 48 75 51 / 0 0 0 0
SOUTH PADRE ISLAND 64 58 66 62 / 10 10 10 0
BAYVIEW/PORT ISABEL 66 53 70 57 / 10 10 10 0
BRO WATCHES/WARNINGS/ADVISORIES
TX...RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR TXZ248>255-351-
353>355.
WIND ADVISORY UNTIL 8 AM CDT THIS MORNING FOR TXZ248-249-252.
WIND ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR TXZ250-251-
253>255-351-353>355-451-454-455.
HIGH RIP CURRENT RISK FROM 7 AM CDT THIS MORNING THROUGH THIS
EVENING FOR TXZ451-454-455.
HIGH SURF ADVISORY FROM 7 AM THIS MORNING TO 7 PM CDT THIS
EVENING FOR TXZ451-454-455.
GM...GALE WARNING UNTIL 7 PM CDT THIS EVENING FOR GMZ130-132-135-150-
155-170-175.
SHORT TERM...23-EVBUOMA
LONG TERM....23-EVBUOMA
AVIATION...63-KC
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