textproduct: Houston/Galveston

KEY MESSAGES

- Heat advisory continues through 6 PM. Peak heat indicies of 106- 109F remain expected.

- Scattered afternoon thunderstorms through the weekend.

- Hot temperatures continue through next week, with daily afternoon storms along the coast.

DISCUSSION

Issued at 1254 PM CDT Sat Sep 12 2026

Isolated-to-scattered showers and thunderstorms remain expected this afternoon, gradually tapering off this evening. Flow aloft is very weak and these should not amount to much. The Heat Advisory remains unchanged for today with highs in the mid-to-upper 90s combined with dewpoints in the mid-to-upper 70s which will yield heat indicies around 106-109. Use caution if taking part in outdoor activities. Moisture parameters slightly improve Sunday and despite the continued lack of forcing with the benign upper pattern, afternoon sea breeze initiated convection looks to be a bit more widespread. Otherwise temperatures will be similar as today. Although we remain just below Heat Advisory criteria at this time, heat indicies will be widespread in the mid-triple digits, so again use caution outdoors.

A broad closed upper level high pressure will develop over the Tennessee Valley on Monday, curtailing any unsettled weather. Typical afternoon sea breeze convection should persist, but remain very isolated. An upper low approaching from the northeast will gradually displace the ridge mid-to-late week, however it will not be very strong and should not lead to any significant changes to the hot and mostly dry pattern. Active weather may return next weekend as Pacific moisture looks to track farther eastward, but it remains too far out to determine specific details.

AVIATION

(18Z TAF Issuance) Issued at 1254 PM CDT Sat Sep 12 2026

VFR conditions will prevail across the region this afternoon and evening. Isolated to scattered showers and storms are possible this afternoon, though coverage should generally remain near the IAH-HOU- SGR terminals. Given low to moderate confidence in timing and coverage, have continued with PROB30. Any activity should taper off by early this evening. Winds will generally remain from the SSE around 8 to 12 kts with occasional gusts up to 15 to 18 kts through early this evening. Winds will become light and variable overnight, before transitioning to the SSW to S by late morning. The afternoon hours bring another chance of showers and storms. Outside of any strong storms and areas of fog (particularly at CXO), VFR conditions are expected through most of the period.

MARINE

Issued at 1254 PM CDT Sat Sep 12 2026

Winds around 10-15 kts (peaking this evening and Sunday evenings) will continue through the weekend with seas of 2-4 ft. Daily thunderstorm chances will continue, with slightly higher chances Sunday afternoon near the coast and lingering into the overnight hours for the Gulf.

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 77 98 77 97 / 0 10 0 20 Houston (IAH) 78 95 78 94 / 50 30 0 40 Galveston (GLS) 84 91 84 91 / 20 20 10 20

HGX WATCHES/WARNINGS/ADVISORIES

TX...Heat Advisory until 6 PM CDT this evening for TXZ163-164-176-177- 195>199-210>213-226-227-235-236.

GM...None.