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000 FXUS64 KBRO 212357 AAA AFDBRO Area Forecast Discussion...UPDATED National Weather Service Brownsville TX 657 PM CDT Tue Jul 21 2026...New AVIATION...KEY MESSAGES
Updated at 653 PM CDT Tue Jul 21 2026
- Record-breaking high temperatures are possible the next few days with Moderate (level 2 of 4) to Major (level 3 of 4) Heat Risk.
- A Heat Advisory is in effect today for inland Cameron, Willacy, and Kenedy Counties between 12 PM and 7 PM CDT.
- There are still slightly elevated fire weather conditions due to low humidity, though the risk is a little less due to lower winds. Outdoor burning is still not recommended.
- No direct impacts from Tropical Storm Bertha are expected for Deep South Texas, but area beaches could see elevated rip currents and higher surf associated with this system.
DISCUSSION
Issued at 1244 PM CDT Tue Jul 21 2026
High pressure remains dominant over the Central Gulf, which will keep conditions hot and rain-free with high heat indices through the weekend into next week. A Heat Advisory is in effect this afternoon into early evening (12 PM to 7 PM CDT) for inland Kenedy, Willacy, and Cameron Counties, where heat indices up to 113 could occur. Though temperatures/heat indices currently look slightly better for tomorrow, additional heat advisories this week are possible. Record- breaking temperatures are also possible this week into next.
The only chance for rain this next week is Thursday into Thursday night when a small moisture plume from the Gulf could support a few isolated showers and thunderstorms. Chances are low, between 10 to 20 percent. Otherwise, all of Deep South Texas should remain dry through the middle of next week.
The latest guidance for Tropical Storm Bertha still has the system staying well-north of Deep South Texas, impacting the Louisiana and Upper Texas Coast later this week. We are still anticipating no direct impacts for Deep South Texas, but will continue to monitor. Indirect coastal impacts such as elevated surf, an increased risk of life-threatening rip currents, and tidal runup are expected by the end of this week into the weekend.
Fire danger is not as high as it was the past few days due to slightly lower wind speeds, but because conditions are still very dry (especially in the western counties), outdoor burning is still not recommended.
AVIATION
(00Z TAFS) Issued at 653 PM CDT Tue Jul 21 2026
VFR TAFs continue, with breezy southeasterly winds (around 13-15 knots, gusting to 20 knots) this evening becoming light and/or variable overnight before picking back up to 10-15 knots by tomorrow afternoon, out of the southeast.
MARINE
Issued at 1244 PM CDT Tue Jul 21 2026
Conditions are expected to be overall favorable for the next few days with low to moderate seas and light to moderate southerly winds. Conditions later this week depend on how much swell is generated by Tropical Storm Bertha to the north, which could potentially increase wave heights. At this time, there is some uncertainty. If swell remains low, then conditions should remain overall favorable, excepting some afternoon periods of SCEC in the Bay. However, if a higher swell is generated, this could potentially make conditions more adverse into the weekend.
PRELIMINARY POINT TEMPS/POPS
| Temperatures | Chance of Precipitation | |||||||
|---|---|---|---|---|---|---|---|---|
| Location | Tonight | Tomorrow | Tomorrow night | Next day | Tonight | Tomorrow | Tomorrow night | Next day |
| BROWNSVILLE | 78 ℉ | 100 ℉ | 79 ℉ | 99 ℉ | 0% | 0% | 0% | 10% |
| HARLINGEN | 74 ℉ | 105 ℉ | 75 ℉ | 101 ℉ | 0% | 0% | 0% | 10% |
| MCALLEN | 76 ℉ | 108 ℉ | 78 ℉ | 105 ℉ | 0% | 0% | 0% | 10% |
| RIO GRANDE CITY | 76 ℉ | 107 ℉ | 78 ℉ | 105 ℉ | 0% | 0% | 0% | 10% |
| SOUTH PADRE ISLAND | 79 ℉ | 90 ℉ | 80 ℉ | 89 ℉ | 0% | 0% | 0% | 10% |
| BAYVIEW/PORT ISABEL | 76 ℉ | 98 ℉ | 77 ℉ | 96 ℉ | 0% | 0% | 0% | 10% |
BRO WATCHES / WARNINGS / ADVISORIES
TX...Heat Advisory until 7 PM CDT this evening for TXZ251-254-255.
GM...None.
SHORT TERM...55-MM LONG TERM....55-MM AVIATION...65-Irish