textproduct: Houston/Galveston

KEY MESSAGES

- Heat Advisory remains in effect. Hot conditions will persist through next week. - Isolated thunderstorms possible late Saturday afternoon / evening. Best chance of a storm will be across our northern zones.

DISCUSSION

Issued at 1059 PM CDT Fri Aug 21 2026

Taking a look at the large-scale view of the weather pattern via water vapor satellite imagery and 500 MB RAP analysis, one can see that the strong mid/upper ridge centered over the Four Corners region continues to be the dominant force over the Texas atmosphere. A quick glance at the global ensemble data shows that this ridge will likely remain dominant through at least the middle to later part of next week. If you have not been enjoying the recent very hot conditions, then I send to you my profound apologies. This pattern will likely skew temperatures hotter than normal through the next week, though perhaps we can dial the heat down slightly by the end of next week. Triple digit heat will be the norm across inland Southeast Texas, with low/mid 90s at the beaches. Humidity will easily make it feel 5-10 degrees hotter. A heat advisory is in effect through Sunday. I won't be surprised if we end up issuing advisories well into the upcoming week.

Perhaps a few of you will experience some heat relief in the form of an isolated afternoon / evening thunderstorm. There was actually quite a bit of thunderstorm activity east of our region on Friday, with isolated activity occurring in our Piney Woods zones. Though Saturday's atmosphere will nearly the same synoptically, there could modest mesoscale differences that bring isolated storms to areas that remained dry on Friday. For example, we'll need to watch some of these outflow boundaries approaching from the east thanks to Friday's Louisiana storms. There will also be additional weak disturbances in the flow aloft worth watching. Monitoring these weak disturbances will likely be a theme throughout the next week. But generally speaking, expect mostly dry and very hot conditions through the forecast period.

Self

AVIATION

(12Z TAF Issuance) Issued at 528 AM CDT Sat Aug 22 2026

A few sites may see some MVFR cigs/vis through around 14Z this morning. Thereafter, VFR conditions are expected. SW winds this morning will be at 5-10 kts, turning S-SE during the mid-late afternoon hours. Winds will once again become S-SW during the night hours. With respect to rain, there's a chance for isolated showers/storms later today and this evening. Confidence of actual location of these showers/storms is low, thus, didn't include wx for this TAF issuance but may be added in the 18Z issuance or as AMDs.

Cotto

MARINE

Issued at 1059 PM CDT Fri Aug 21 2026

South to southwest winds are expected to average 10-15 knots over the next several days. Gusts to 20 knots will be possible in the bays during the afternoon and in the Gulf during the overnight. Thunderstorm activity is expected to the north of the region Saturday. We cannot rule out a storm making it down to the coast late afternoon and evening. Gulf seas should average 2 to 3 feet over the next week.

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 103 79 103 78 / 20 10 0 0 Houston (IAH) 103 81 102 80 / 20 10 0 0 Galveston (GLS) 93 82 92 83 / 10 10 0 0

HGX WATCHES/WARNINGS/ADVISORIES

TX...Heat Advisory until 7 PM CDT Sunday for TXZ163-164-176>179- 195>200-210>214-226-227-235>238-300-313-335>338-436>439.

GM...None.