textproduct: Houston/Galveston

KEY MESSAGES

- Scattered showers and isolated thunderstorms Sunday, better chance of thunderstorms in the morning near 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 1200 AM CDT Sun Oct 4 2026

A west Gulf trough, enveloped in very high PWATs, is producing scattered shower and thunderstorm activity along with gusty coastal and Gulf northeast winds. Some showers and thunderstorms Saturday evening were heavy, which makes sense given the widespread 2.0+ inch PWATs. That being said, rainfall totals thus far this weekend have generally been manageable since most of the heavier action has remained offshore (not too surprising). This will probably be a theme today, with scattered inland activity and heavier showers and storms over the Gulf. Cannot rule out some of these Gulf showers and storms moving ashore at the coast Sunday morning. Given tides are running higher than normal, this will make coastal areas a little more vulnerable to localized flooding.

As we head into Monday, a ~1025MB sfc high is expected to build over the planes. Meanwhile, the Gulf trough should push farther offshore. The building gradient should enhance NE LL flow, advecting somewhat cooler and much drier air into the region. Expect low humidity and afternoon temperatures in the 80s Monday - Wednesday. Overnight lows are expected to drop into the 60s away from the coast and outside Houston's urban heat island. Though I cannot rule out morning lows as cool as the upper 60s within the city.

The aforementioned trough could make its return later in the week. The sfc high should push eastward, while a potential cut-off low like feature approaches from the west. This would open the door for synoptic-scale lift along with increasing moisture levels and the potential return for onshore flow (depending on exact positioning of LL features). Therefore, the late-week forecast features rising humidity and increasing shower/thunderstorm chances.

For those yearning for "real" fall-like weather, there is decent ensemble support for a stronger cold front by the middle of the month. Honestly, the data in the ensemble meteograms is probably the strongest model support I've seen for a strong cold front reaching SE Texas thus far this season. But considering how far out this theoretical front is, I'd say taper your excitement for now.

Self

AVIATION

(06Z TAF Issuance) Issued at 1110 PM CDT Sat Oct 3 2026

MVFR cigs prevailing at most TAF sites until a drop to IFR cigs by 07 to 09Z. Currently, we anticipate cigs/vis to improve starting around 16Z with VFR returning by 20 to 22Z, but there are models which keep IFR cigs deep into the afternoon. For now, we wrote in a SCT008 with an MVFR OVC deck at 16Z to hint at the potential of those IFR cigs sticking around. Isolated/scattered showers and thunderstorms will primarily be confined to the coast, but storms could appear further north, especially in the evening. Any showers/thunderstorms that develop over the terminals bring with them the potential for sub-VFR cigs/vis and gusty winds. Winds during this period will generally be out of the NNE/NE at 8-12 kts, with gustier winds closer to the coast.

MARINE

Issued at 1110 PM CDT Sat Oct 3 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 numberous showers and thunderstorms likely today. The chance of showers and thunderstorms will shift farther offshore Monday- Wednesday.

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 84 68 81 67 / 50 40 30 10 Houston (IAH) 88 73 83 72 / 50 60 30 10 Galveston (GLS) 87 78 85 78 / 50 90 80 40

HGX WATCHES/WARNINGS/ADVISORIES

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

GM...Small Craft Should Exercise Caution through Monday afternoon for GMZ330-335.

Small Craft Advisory until 1 PM CDT Monday for GMZ350-355-370- 375.