textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 630 PM CDT Mon Mar 9 2026

Key Messages:

- Unseasonably warm and humid weather is expected through mid- week, with wind speeds picking up tomorrow due to a tightened pressure gradient.

- A cold front is expected Wednesday evening into Thursday, which will bring a low (20-30%) chance of precipitation to the region ahead of the front.

- Following the frontal passage, elevated fire danger along with beach and marine hazards will become a concern for Wednesday and Thursday.

- Temperatures will be unseasonably warm again by the weekend, with no rain expected.

DISCUSSION

Issued at 1217 PM CDT Mon Mar 9 2026

Unseasonably warm temperatures and rain-free (but humid) conditions will prevail the first half of the week throughout Deep South Texas. Winds are expected to increase tomorrow and become gusty due to a tightening pressure gradient over the area. A Pacific trough is expected to move across the Southern Plains Wednesday, which will bring a cold front to our region Wednesday night into Thursday morning. Earlier guidance had suggested that it would be a dry cold front with no associated precipitation. Though the air behind the cold front is expected to be exceptionally dry, newer guidance suggests there will be a low (20-30%) chance of precipitation ahead of the front in the warm sector on Tuesday night into Wednesday, with the best chances in the Northern Ranchlands.

This cold front is expected to cool daytime high temperatures around ten to fifteen degrees. Highs will reach the upper 70s/lower 80s on Thursday, but the cooler air is not expected to last. Warming will commence on Friday with highs reaching the mid-80s, and temperatures will be back in the upper 80s/lower 90s in time for the weekend. Low temperatures will be in the upper 50s/lower 60s Thursday morning and remain cool Friday morning as well, before warming into the 60s for the weekend.

Relative humidity is expected to decrease rapidly following the frontal passage, which will elevate fire concerns for Wednesday and Thursday. Given that the region is already in a state of D3 and D4 drought, it will be very easy for anything to catch on these days due to the dryness of air and fuels. If wind speeds trend any higher on future model guidance, Fire Danger Statements and/or Red Flag Warnings may be needed on these days.

There is a moderate risk of life-threatening rip currents at area beaches tonight and tomorrow. This risk could increase Wednesday into Thursday.

AVIATION

(00Z TAFS) Issued at 630 PM CDT Mon Mar 9 2026

MVFR ceilings are forecast to develop overnight, with VFR conditions returning late Tuesday morning into early Tuesday afternoon. Gusty southeasterly winds will continue this evening, with gusts likely diminishing overnight. Wind gusts are forecast to increase again by mid morning.

MARINE

Issued at 1217 PM CDT Mon Mar 9 2026

SCEC conditions are expected to develop this afternoon and tonight into tomorrow as a pressure gradient tightens ahead of an approaching low pressure system. Some areas may even see Small Craft Advisory conditions tomorrow night. Conditions will slightly improve on Wednesday before winds and wave heights pick up again on Thursday. Conditions should become more favorable again for the weekend on Friday.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 72 87 72 93 / 0 0 0 0 HARLINGEN 69 90 70 95 / 0 0 10 10 MCALLEN 73 93 74 97 / 10 0 10 0 RIO GRANDE CITY 71 95 69 94 / 10 0 20 0 SOUTH PADRE ISLAND 72 79 72 84 / 0 0 0 10 BAYVIEW/PORT ISABEL 70 86 70 91 / 0 0 0 10

BRO WATCHES/WARNINGS/ADVISORIES

TX...None. GM...None.