textproduct: Houston/Galveston

KEY MESSAGES

- Scattered showers and isolated thunderstorms through this afternoon. Most of the activity will remain confined to the coast.

- Much lower humidity and cooler nights Monday - Wednesday.

- After a break in the rain/humidity, we should see chances ramp back up across parts of the region Thur-Sat (especially coastal areas).

DISCUSSION

Issued at 203 PM CDT Sun Oct 4 2026

Today the rain showers are driven by two different features in the coastal and Brazos Valley regions. First, coastal troughing and its associated stationary boundary remain glued to the coast through tomorrow morning before finally exiting. The PWAT's remain in the 90TH percentile, resulting in continual rain showers. These showers will periodically meander inland, while the majority remain off shore. Second, a shortwave trough feature continues to drop south from the Brazos Valley into the Piney Woods, also producing rain showers. Activity associated with these features is not anticipated to become convective, with mostly cloudy skies keeping the atmosphere more stable. While both features are over the region, minimum interaction is anticipated as marginally increased surfaced based CAPE interacts with the weakening shortwave trough initiating showers over the eastern counties before reaching the I-10 corridor. All across the area the one similarity is a continual NNE breeze with occasional gusts that keep temperatures mild.

Monday, a surface high pressure system begins to build in from the Plains and initiates a stronger gradient with expanded NE flow. This increases the probability of bringing decreased dewpoints and "cooler" temperatures. 90th percentile temperatures remain in the mid-upper 80's, so about a 10% chance of highs reaching into the 90s. Overnight lows also become more seasonally normal. Temperatures north of I-10 will lower into in the mid 60's while the city and coastline remain in the low-mid 70's.

In the longer forecast period the surface high pressure sticks around through about mid week before lifting northward. A trough moves northward through the Gulf and hugs the coastline as moisture returns to the area around the middle of next week. This compresses the gradient and brings back SSE flow. Thus humidity, temperatures and rain chances all increase at the end of the work week into the next weekend.

Whitaker/Bailey

AVIATION

(00Z TAF Issuance) Issued at 642 PM CDT Sun Oct 4 2026

MVFR conditions persist through this evening as a widespread cloud deck hangs over all TAF sites. This cloud deck will gradually clear from NW to SE through the overnight hours and into the day tomorrow. The northernmost TAF sites will see a return to VFR first, by about 05 to 08Z. There is some uncertainty over how long MVFR cigs will last at IAH, with some models taking these cigs into the afternoon. Based on the latest HREF/NBM guidance, we decided to have VFR conditions appear by 12Z at IAH, but left in a SCT015 to hint at the potential for those MVFR cigs sticking around. Since they are closest to the coastal moisture, the southernmost TAF sites have VFR conditions return by tomorrow afternoon/evening (19 to 21Z). Rain will likely remain offshore during this period, but storms could pop up near LBX and GLS during the evening and overnight hours. Winds will be NNE/NE during this period, with gustier conditions along the coast.

JMG

MARINE

Issued at 203 PM CDT Sun Oct 4 2026

The presence of a trough in the western Gulf and the gradual building of a surface high over the central United States will steepen the gradient and enhance northeast winds and seas through Monday, and likely through Tuesday. Small Craft Advisory is in effect for the Gulf waters through Monday, and could be extended further. There will also be periods of Small Craft level winds in the bays, particularly lower bays. Winds could gust over 30 knots at times, especially over the Gulf and near/within thunderstorms. We haven't issued an advisory for the bays but cannot rule out an advisory being warranted. Scattered to numerous showers and thunderstorms continue this afternoon. The chance of showers and thunderstorms will shift farther offshore Monday- Wednesday.

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 67 84 64 86 / 10 0 0 0 Houston (IAH) 72 87 71 88 / 20 0 0 0 Galveston (GLS) 77 86 77 87 / 50 10 10 10

HGX WATCHES/WARNINGS/ADVISORIES

TX...High Rip Current Risk through Monday afternoon for TXZ436>439.

GM...Small Craft Advisory until 1 PM CDT Monday for GMZ330-335-350- 355-370-375.