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

(00Z TAF Issuance) Issued at 536 PM CDT Sat Sep 12 2026

Gusty winds will ease and become light this evening. Cloud decks will lower to around 1500-2000ft overnight, and could briefly fill in to produce MVFR CIGS early Sunday morning. Isolated patchy fog will also be possible at fog prone locations like KCXO. CIGs/Fog should clear around or by the late morning hours. Diurnally driven showers/storms will be possible on Sunday, mainly over the coast during the morning, then inland during the afternoon. Overall chances for showers/storms look slightly better on Sunday compared to Saturday. Any convection that does develop should tapper off into Sunday evening, while winds becoming light once again.

03

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 76 97 / 10 0 0 10 Houston (IAH) 79 95 78 94 / 0 20 0 30 Galveston (GLS) 84 91 84 91 / 0 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.