146
FXUS64 KBRO 171123 AAA
AFDBRO
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BROWNSVILLE TX
623 AM CDT THU SEP 17 2026
..NEW AVIATION
KEY MESSAGES
UPDATED AT 622 AM CDT THU SEP 17 2026
- A SPECIAL WEATHER STATEMENT (SPS) IS POSSIBLE AGAIN ACROSS THE
COUNTIES ALONG AND/OR EAST OF US-281 ON THURSDAY FOR HEAT
INDICES OF 108-111 F, GENERALLY OCCURRING WITHIN THE HOURS OF
12 PM TO 6 PM.
- NEAR DAILY LOW TO MEDIUM CHANCES OF RAIN CONTINUE INTO THE
MIDDLE OF NEXT WEEK, WITH THE MOST WIDESPREAD AND HIGHEST
CHANCES (UP TO A 50-60% CHANCE) ON THURSDAY AND FRIDAY.
- INCREASED CLOUD COVER SHOULD HELP MAINTAIN MODERATE TO MAJOR
RISKS OF HEAT-RELATED ILLNESSES (LEVELS 2/4 AND 3/4).
- A LOW RISK OF LIFE-THREATENING RIP CURRENTS CONTINUES THROUGH
THURSDAY AFTERNOON.
DISCUSSION
ISSUED AT 1043 PM CDT WED SEP 16 2026
ASIDE FROM A MORE EXPANSIVE AREA OF TRIPLE DIGITS POSSIBLE THIS
SUNDAY AND NEXT MONDAY, INCREASED CLOUD COVERAGE AND DAILY LOW OR
LOW TO MEDIUM CHANCES OF RAIN SHOULD LIMIT MOST INLAND HIGH
TEMPERATURES TO THE UPPER 90S INTO THE MIDDLE OF NEXT WEEK, THOUGH
LOWER 100S ARE STILL POSSIBLE ALONG/WEST OF US-281, MOST WIDESPREAD
OVER STARR AND ZAPATA COUNTIES. DEPENDENT ON THE DEVELOPMENT OF
SHOWERS/THUNDERSTORMS AND MODEL GUIDANCE TRENDS THROUGHOUT TONIGHT
AND THURSDAY MORNING, ANOTHER SPS MAY ISSUED BY THE ONCOMING SHIFTS
FOR THE COUNTIES ALONG AND/OR EAST OF US-281 FOR HEAT INDICES OF 108-
111 F THURSDAY AFTERNOON INTO EARLY THURSDAY EVENING.
WEATHER PATTERN-WISE, EASTERLY TO NORTHEASTERLY WINDS CIRCULATING
ABOUT A SURFACE HIGH PRESSURE SPILLING FROM THE EAST COAST TO THE
GULF IS PROGGED TO ADVECT A PLUME OF DEEP GULF MOISTURE, WITH PWATS
MEASURING UP TO 2.0-2.4+ IN., ACROSS DEEP SOUTH TEXAS BEGINNING
TONIGHT AND PEAKING DURING THE DAY ON THURSDAY; CHANCES OF RAIN
INCREASE NEAR THE COAST LATE TONIGHT TO A LOW (15-30%) CHANCE BY
THURSDAY MORNING, SPREADING WESTWARD AND INCREASING ALONG THE
SEABREEZE BOUNDARY TO A LOW TO MEDIUM (20-40%) ALONG/WEST OF
US-281 BY THE AFTERNOON/EVENING HOURS ON THURSDAY, FOLLOWED BY A
LOW TO MEDIUM (20-40%) CHANCE ALONG/EAST OF US-281 THURSDAY NIGHT
AND A LOW TO MEDIUM (20-50%) CHANCE ACROSS THE REGION ON FRIDAY. IN
GENERAL, WE CURRENTLY EXPECT THAT MOST AREAS WILL SEE ANYWHERE
FROM LITTLE OR NO RAINFALL TO AS MUCH AS AROUND 0.20-0.30 OF AN
INCH IN TOTAL THURSDAY INTO FRIDAY. NONETHELESS, GIVEN ABOVE
AVERAGE MOISTURE CONTENT, HEAVY RAIN AND LOCALIZED MINOR FLOODING
ARE POSSIBLE WITHIN SLOWER-MOVING OR TRAINING OF CONVECTION AS
WELL AS FREQUENT LIGHTNING AND/OR HIGHER GUSTS WITHIN DEEPER
THUNDERSTORMS. ADDITIONALLY, INCREASED CLOUD COVER ON FRIDAY
FOLLOWED BY DRIER AIR INFILTRATING THE REGION ON SATURDAY ARE
ANTICIPATED TO IMPROVE RISKS OF HEAT-RELATED ILLNESSES FROM
MODERATE TO MAJOR ON THURSDAY TO MOSTLY MODERATE WITH HEAT INDICES
RANGING AROUND 103-109 F.
SUBSIDENCE ASSOCIATED WITH A HIGH PRESSURE ALOFT RETREATING BACK TO
THE SOUTHERN PLAINS BY FRIDAY NIGHT CUTS DOWN ON RAIN CHANCES TO A
LOW (10-20%) CHANCE ALONG/EAST US-281 ON SATURDAY AND SUNDAY
AFTERNOON. MEANWHILE, THE HIGH PRESSURE BEGINS TO WEAKEN, CAUSING
HEIGHTS TO LOWER THROUGHOUT THE WEEKEND AND INTO THE MIDDLE OF NEXT
WEEK, ALLOWING FOR MOISTURE AND DIVERGENCE ALOFT ASSOCIATED WITH AN
UPPER LEVEL LOW SPINNING OVER THE GULF TO GRADUALLY INCREASE AND
EXPAND CHANCES OF RAIN FROM A LOW (15-30%) ON MONDAY A LOW TO MEDIUM
(20-40%) CHANCE ACROSS MOST OF THE REGION BY THE MIDDLE OF NEXT
WEEK. MODERATE TO MAJOR HEAT RISKS RETURN BY SUNDAY AND ADDITIONAL
SPSS FOR HEAT INDICES OF 108-111 F ARE POSSIBLE.
AVIATION
(12Z TAFS)
ISSUED AT 622 AM CDT THU SEP 17 2026
VFR WILL PREVAIL AT THE AERODROMES THROUGH THE NEXT 24 HOURS. A
TEMPO HAS BEEN RETAINED AT THE AERODROMES FOR THE POSSIBILITY OF
SEABREEZE CONVECTION.
MARINE
ISSUED AT 1043 PM CDT WED SEP 16 2026
GENTLE TO MODERATE NORTHEASTERLY TO EASTERLY WINDS CONTINUE AND
SLIGHT TO MODERATE (2-4 FT) SEAS BUILD TO MODERATE (3-5 FT) BY
THURSDAY NIGHT. GENTLE TO MODERATE EASTERLY TO SOUTHEASTERLY WINDS
AND SLIGHT TO MODERATE (1-3 FT) SEAS RETURN OVER THE WEEKEND.
MEANWHILE, CHANCES OF RAIN INCREASE LATE TONIGHT TO AS MUCH AS A
MEDIUM TO HIGH (40-70%) CHANCE ON THURSDAY, WITH LOW TO MEDIUM
CHANCES CONTINUING INTO SATURDAY AND INTO NEXT WEEK.
PRELIMINARY POINT TEMPS/POPS
BROWNSVILLE 95 80 95 78 / 30 40 30 10
HARLINGEN 98 76 97 74 / 20 30 30 10
MCALLEN 99 80 99 77 / 40 30 50 0
RIO GRANDE CITY 100 78 98 75 / 30 30 50 0
SOUTH PADRE ISLAND 88 81 89 81 / 30 50 30 10
BAYVIEW/PORT ISABEL 94 79 94 78 / 20 40 30 10
BRO WATCHES/WARNINGS/ADVISORIES
NONE.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page