502
FXUS64 KBRO 031826
AFDBRO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BROWNSVILLE TX
126 PM CDT SUN MAY 3 2026
..NEW DISCUSSION, AVIATION, MARINE
KEY MESSAGES
UPDATED AT 119 PM CDT SUN MAY 3 2026
KEY MESSAGES:
* WARMTH/HEAT BUILDS THROUGH WEDNESDAY WITH WEDNESDAY PROJECTED TO
BE THE HOTTEST DAY OF THE WEEK.
* WIDESPREAD MODERATE (LEVEL 2 OF 4) HEAT RISK IS EXPECTED ON
TUESDAY AND WEDNESDAY WITH POCKETS OF MAJOR (LEVEL 3 OF 4) HEAT
RISK ON WEDNESDAY; HEAT INDICES ARE EXPECTED TO RANGE BETWEEN 100-
110F DEGREES TUESDAY AND WEDNESDAY.
* DAY-TO-DAY OR NEAR DAY-TO-DAY CHANCES FOR SHOWERS AND
THUNDERSTORMS ARE POSSIBLE THURSDAY THROUGH NEXT SUNDAY AS THE
WEATHER PATTERN LOOKS TO BECOME WETTER OR MORE ACTIVE.
DISCUSSION
ISSUED AT 119 PM CDT SUN MAY 3 2026
THE MAIN WEATHER CONCERN DURING THE FORECAST PERIOD ACROSS DEEP
SOUTH TEXAS AND THE RIO GRANDE VALLEY WILL BE FOCUSED ON THE
INCREASED PROSPECTS FOR SHOWERS AND THUNDERSTORMS THURSDAY THIS
WEEK THROUGH AT LEAST NEXT WEEKEND AS THERE ARE INCREASING SIGNS
THAT THE WEATHER PATTERN DURING THE EARLY TO MIDDLE PARTS OF MAY
COULD BECOME ACTIVE/WETTER/STORMIER.
TODAY THROUGH WEDNESDAY NIGHT (RAIN-FREE WITH BUILDING HEAT
RISK)...
RAIN-FREE WEATHER CONDITIONS ARE EXPECTED TO PERSIST TODAY THROUGH
WEDNESDAY NIGHT, COURTESY OF A SFC HIGH PRESSURE SYSTEM IN PLACE AND
A RIDGE AXIS PASSING OVERHEAD FROM WEST TO EAST. DURING THIS
TIMEFRAME OR THROUGH WEDNESDAY, THE WARMTH/HEAT WILL STEADILY
STRENGTHEN EACH DAY. THIS WARMING TREND THROUGH WEDNESDAY WILL BE
AS A BYPRODUCT OF THE LOCAL FORECAST AREA PLACED ON THE NORTHERN
FRINGES OF A STRENGTHENING 588-591 DAM HEAT RIDGE. TEMPERATURE
ANOMALIES DURING THIS WARMING TREND WILL GO FROM BELOW NORMAL
LEVELS TODAY TO ABOVE NORMAL LEVELS BY TUESDAY AND WEDNESDAY. HIGH
TEMPS WILL GO FROM THE LOW TO MID 80S THIS AFTERNOON TO THE UPPER
80S ON MONDAY TO THE LOW TO MID 90S ON TUESDAY TO FINALLY THE MID
TO UPPER 90S ON WEDNESDAY.
HEAT INDICES RANGING BETWEEN 100-110F DEGREES (HIGHEST ALONG THE
UPPER VALLEY) WILL SCORE WIDESPREAD MODERATE (LEVEL 2 OF 4) HEAT
RISK ON TUESDAY. WIDESPREAD HEAT INDICES ACROSS DEEP SOUTH TEXAS
AND THE RIO GRANDE VALLEY RANGING BETWEEN 105-110F DEGREES WILL
SCORE WIDESPREAD MODERATE (LEVEL 2 OF 4) HEAT RISK WITH POCKETS OF
MAJOR (LEVEL 3 OF 4) HEAT RISK ON WEDNESDAY. OVERNIGHT LOW TEMPS
TONIGHT ARE PROGGED TO BE IN THE 60S ACROSS DEEP SOUTH TEXAS.
MONDAY NIGHT THROUGH WEDNESDAY NIGHT, OVERNIGHT LOWS ARE PROGGED
TO BE IN THE 70S. ON TUESDAY, AN ENHANCED SFC PRESSURE GRADIENT
WILL RESULT IN A BREEZY DAY WITH SOUTHERLY WINDS 20-30 MPH AND
GUSTS BETWEEN 30-40 MPH.
THURSDAY THROUGH NEXT SUNDAY (AN ACTIVE, WETTER, STORMIER PATTERN
COULD DEVELOP)...
ATTENTION TURNS TO THE POTENTIAL FOR SHOWERS AND THUNDERSTORMS, AND
THE CHANCE FOR SOME MUCH-NEEDED RAINFALL THAT COULD FURTHER ADDRESS
THE REMAINING DROUGHT CONDITIONS ACROSS THE REGION THURSDAY
THROUGH AT LEAST NEXT WEEKEND.
MULTIPLE GLOBAL COMPUTER MODELS AND AI/ML ENSEMBLES ARE DEPICTING A
SPLIT-FLOW JET STREAM REGIME ACROSS THE CONTIGUOUS U.S. THIS WEEK
THROUGH NEXT WEEKEND. THIS LARGE-SCALE PATTERN WILL FEATURE AN
ANOMALOUSLY STRONG MID-UPPER LOW/TROUGH OVER THE SOUTHWESTERN U.S.
THIS TROUGH WILL HELP TO ENHANCE OR ACTIVATE THE SOUTHERN BRANCH
JET STREAM OR SUB-TROPICAL JET OVER NORTHERN MEXICO AND ALL OF
TEXAS INCLUDING OUR LOCAL FORECAST AREA THURSDAY THROUGH NEXT
WEEKEND. SEVERAL PERTURBATIONS/IMPULSES WILL TRACK OVERHEAD ALONG
THIS SOUTHERN BRANCH JET STREAM. MEANWHILE, DURING THIS TIMEFRAME
(THURSDAY THROUGH NEXT WEEKEND), SOUTHERLY WINDS WILL HELP TO
INCREASE DEEP TROPICAL MOISTURE FROM THE GULF. GLOBAL FORECAST
MODELS ARE INDICATING PRECIPITABLE WATER (PWAT) VALUES RISING FROM
1-1.5 INCHES TODAY THROUGH WEDNESDAY TO 1.5-2.3 INCHES THURSDAY
THROUGH NEXT WEEKEND. INSTABILITY VALUES WILL ALSO INCREASE
ALONGSIDE INCREASED MOISTURE ADVECTION. FINALLY, A COLD FRONT IS
EXPECTED TO APPROACH THE REGION THURSDAY INTO FRIDAY BEFORE
STALLING OR WASHING OUT TO OUR SOUTH.
MULTIPLE MID-UPPER ENERGIES/SHORTWAVES, SOME OF WHICH CAN BE
VIGOROUS, COMBINED WITH INCREASED MOISTURE AND INSTABILITY VALUES,
AND AN APPROACHING COLD FRONT COULD POTENTIALLY RESULT IN AN
ACTIVE/WET/STORMY WEATHER PATTERN TAKING SHAPE WITH DAY-TO-DAY OR
NEAR DAY-TO-DAY CHANCES FOR SHOWERS AND THUNDERSTORMS DEVELOPING
OVER DEEP SOUTH TEXAS AND THE RIO GRANDE VALLEY THURSDAY THROUGH
AT LEAST NEXT WEEKEND. CURRENTLY, WE HAVE LOW-MEDIUM (20-50%)
CHANCES FOR SHOWERS AND THUNDERSTORMS THURSDAY THROUGH NEXT SUNDAY
WITH SOME OF THE GREATER PROBABILITIES THURSDAY THROUGH FRIDAY
AND THE LOWER PROBABILITIES SATURDAY AND SUNDAY.
WE WILL CONTINUE TO MONITOR FORECAST MODEL AND PROBABILITY FOR
PRECIPITATION (POP) TRENDS IN THE DAYS AHEAD. WE CURRENTLY AREN'T
OUTLOOKED UNDER ANY RISK FOR SEVERE WEATHER OR EXCESSIVE RAINFALL,
BUT THAT COULD CHANGE. GIVEN THE ELEVATED ATMOSPHERIC MOISTURE
CONTENT THAT WILL BE IN PLACE, ANY SHOWERS OR THUNDERSTORMS THAT
DEVELOP WILL HAVE THE CAPABILITIES OF PRODUCING HEAVY RAINFALL,
WHICH AT THE VERY LEAST CAN CREATE INSTANCES OF PONDING AND
LOCALIZED FLOODING.
THE CLIMATE PREDICTION CENTER (CPC) HAS A MEDIUM (50-60%) CHANCE FOR
A WETTER THAN NORMAL PATTERN IN IT'S 6-10 DAY (MAY 8-12) AND A
MEDIUM (40-50%) CHANCE FOR A WETTER THAN NORMAL PATTERN IN IT'S 8-14
DAY (MAY 10-16) TIMEFRAME, WHICH SUGGEST THAT AN ACTIVE/STORMIER
PATTERN COULD PERSIST FROM EARLY MAY (LATER THIS WEEK) THROUGH THE
MIDDLE PARTS OF MAY.
DESPITE THE RECENT GREEN UP AND IMPROVED DROUGHT CONDITIONS FROM
PREVIOUS RAINS IN APRIL, ADDITIONAL RAINFALL IS NEEDED AND WILL BE
BENEFICIAL IN ADDRESSING THE REMAINING DROUGHT CONDITIONS OVER THE
REGION. AS OF APRIL 28TH, THE U.S. DROUGHT MONITOR HAD D1 (MODERATE
DROUGHT) TO D3 (EXTREME DROUGHT) DESIGNATIONS OVER DEEP SOUTH TEXAS
WITH ABOUT 59% OF THE REGION UNDER A D2 (SEVERE DROUGHT), 2% UNDER A
D3 (EXTREME DROUGHT), AND THE REMAINING UNDER A D1 (MODERATE
DROUGHT).
TEMPERATURES THURSDAY THROUGH NEXT SUNDAY WILL RUN NORMAL TO
SLIGHTLY ABOVE NORMAL LEVELS, BUT SLIGHTLY COOLER THAN WEDNESDAY,
DUE TO THE WEAKENING COOL FRONT AND THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS EACH DAY. HIGH TEMPERATURES THURSDAY THROUGH NEXT
SUNDAY ARE PROGGED TO CLIMB INTO THE UPPER 80S TO LOWER 90S.
OVERNIGHT LOW TEMPERATURES WILL REMAIN IN THE 70S EACH NIGHT.
AVIATION
(18Z TAFS)
ISSUED AT 119 PM CDT SUN MAY 3 2026
THROUGH 18Z MONDAY....VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH
THE 18Z TAF PERIOD.
WINDS WILL GENERALLY BE OUT OF THE NORTHEAST THROUGH TODAY WITH
SPEEDS BETWEEN 5-12 KTS. OCCASIONAL GUSTS BETWEEN 15-20 KTS IS
POSSIBLE THIS AFTERNOON. ON MONDAY, WINDS WILL SHIFT OUT OF THE
SOUTHEAST WITH SPEEDS BETWEEN 10-15 KTS. WINDS COULD GUSTS AS HIGH
AS 20-25 KTS.
MARINE
ISSUED AT 119 PM CDT SUN MAY 3 2026
GENERALLY FAVORABLE MARINE CONDITIONS ARE EXPECTED THROUGH NEXT
SUNDAY WITH LIGHT TO MODERATE WINDS AND MODERATE SEAS WITH WAVE
HEIGHTS MAINLY BETWEEN 3-4 FEET. THURSDAY-THURSDAY NIGHT, ADVERSE
MARINE CONDITIONS COULD DEVELOP AND A SMALL CRAFT EXERCISE CAUTION
(SCEC) CONDITIONS ARE POSSIBLE IN RESPONSE TO A COOL FRONT.
PRELIMINARY POINT TEMPS/POPS
BROWNSVILLE 68 84 75 89 / 0 0 0 0
HARLINGEN 63 87 71 92 / 0 0 0 0
MCALLEN 67 88 75 94 / 0 0 0 0
RIO GRANDE CITY 65 88 72 97 / 0 0 0 0
SOUTH PADRE ISLAND 73 80 76 83 / 0 0 0 0
BAYVIEW/PORT ISABEL 68 84 73 88 / 0 0 0 0
BRO WATCHES/WARNINGS/ADVISORIES
TX...HIGH RIP CURRENT RISK UNTIL 7 PM CDT THIS EVENING FOR TXZ451-454-
455.
GM...NONE.
SHORT TERM...23-EVBUOMA
LONG TERM....23-EVBUOMA
AVIATION...23-EVBUOMA
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