textproduct: Houston/Galveston

KEY MESSAGES

- Heat Advisory remains in effect. - Very hot conditions along with a risk of an isolated thunderstorm continues through Wednesday. - Chance of showers and thunderstorms increases later in the week as the heat eases somewhat.

DISCUSSION

Issued at 1121 PM CDT Sun Aug 23 2026

The forecast through Wednesday remains unchanged due to the continued presence of strong mid/upper ridging aloft. Triple digit heat should reign supreme across inland regions, while highs at the beaches average in the low/mid 90s. Lower dew points will mix down to the surface during the afternoon. But even with this mixing, heat index values are expected to reach or exceed advisory criteria today, and possibly again tomorrow and Wednesday. There may be a little more in the way of clouds on Tuesday, which could help keep us a tad less hot and below advisory criteria. Regardless, hazardous heat will occur through Wednesday. An isolated shower/storm cannot be ruled out. Monday-Tuesday PoPs are ~10%.

Global deterministic and ensemble guidance has trended towards a breakdown in the ridge during the second half of the week. This breakdown may be modest, with ensemble mean 500 MB heights only dropping from 595 dam to 592 dam. But the breakdown coupled with increasing disturbances aloft are leading to an upward trend in PoPs for the latter portion of the week (Thursday - Saturday). With increasing clouds and PoPs comes less hot temperatures. Most of the CWA is forecast to be in the seasonably miserable mid 90s by Friday and Saturday. The recent hot and dry spell has placed the area on a trajectory towards drought. So hopefully the increasingly wet signal late week is a trend that continues in future updates.

Self

AVIATION

(06Z TAF Issuance) Issued at 1121 PM CDT Sun Aug 23 2026

VFR conditions prevail at all TAF sites. Winds continue to veer WSW/SW overnight. Winds turn to the SSE and increase to the 7-12 kt range once again tomorrow afternoon. Early tomorrow morning around sunrise, another round of MVFR CIG/VIS is possible, mainly south of I-10. Any MVFR CIGs that develop are expected to be short lived. VIS is expected to drop to 6-9 SM, with localized lower spots. VFR conditions return by about 15Z tomorrow at all TAF sites.

MLG

MARINE

Issued at 1121 PM CDT Sun Aug 23 2026

A typical summertime pattern will continue through much of the next week. Overnight winds are expected to be southwesterly, potentially from the west during the predawn and morning hours. Then winds should become more southerly during the afternoon hours. Winds in the bays should average 10-15 knots with occasional gusts up to 20 knots in the afternoon and early evening hours, before becoming lighter during the overnight hours. Meanwhile, offshore Gulf winds will be highest at night (10-15 knots gusting 20 knots) and lower during the day. Isolated shower or storm possible through Wednesday. Chance of showers and storms increases later in the week.

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 104 78 103 77 / 20 0 0 0 Houston (IAH) 102 80 101 79 / 20 0 10 10 Galveston (GLS) 93 83 93 84 / 0 0 0 0

HGX WATCHES/WARNINGS/ADVISORIES

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

GM...None.