textproduct: Houston/Galveston

KEY MESSAGES

- Hot but less humid through Saturday.

- Rain and storm chances increase next week.

- Cold front mid-week??

DISCUSSION

Issued at 1200 AM CDT Fri Sep 25 2026

With the diffuse boundary already further south and drier northeasterly flow filtering in, slightly cooler conditions are expected early this morning at least for our northern counties. Saturday morning looks even more comfortable with lows in the 60s and low 70s for most of the region. Ridging aloft will remain the primary synoptic influence through the short term, maintaining hot but less humid conditions today and Saturday. Little to no rain is expected with only an isolated shower or storm near the immediate coast.

The synoptic pattern begins to evolve Sunday into early next week as the mid to upper lvl ridge shifts eastward and low level flow turns southerly, initiating a gradual surge in low level moisture. Isolated to scattered diurnally driven showers and thunderstorms become possible on Monday, focused primarily along the seabreeze boundary.

Attention then turns to what could be the next rainmaker for the region mid to late week. Global guidance continues to indicate a fetch of deep Pacific moisture associated with a deepening upper lvl trough digging across the western CONUS and Tropical Cyclone Polo near Baja California. Simultaneously, persistent southerly low lvl flow will maintain a continuous surge of Gulf moisture into SE TX. Global models and ensemble means show a distinct uptick in PWATs mainly Tuesday into the end of the week. However, discrepancies persist regarding the phase of the trough and the associated front. The GFS, including the AIGFS and ensemble members favor a faster, wetter solution for the region. In contrast, the ECMWF remains slightly slower and drier. While specific details regarding timing and rainfall totals remain uncertain, confidence is increasing in a transition toward a wetter pattern from late Tuesday through the end of the week. Precipitation chances and cloud cover will help pull temperatures back closer to seasonal normals.

JM

AVIATION

(12Z TAF Issuance) Issued at 617 AM CDT Fri Sep 25 2026

VFR conditions are expected for the next 30+ hours. 47

MARINE

Issued at 1200 AM CDT Fri Sep 25 2026

Light east to southeast winds overnight will generally transition to the ENE during the day. An isolated shower or storm cannot be ruled out; but in general, drier conditions are expected at least through Sunday. A pattern change is expected next week as a disturbance and associated cold front move through the region. Specific details in timing and impacts across the coastal waters are still uncertain; however, confidence in a wetter pattern for most of the week is increasing. Seas will generally remain in the 1 to 3 ft range through the weekend, potentially increasing by midweek along with elevated winds (reaching Advisory levels) as the aforementioned front moves through.

JM

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 96 69 94 72 / 0 0 0 0 Houston (IAH) 93 73 92 75 / 0 0 0 0 Galveston (GLS) 89 81 89 81 / 0 10 20 10

HGX WATCHES/WARNINGS/ADVISORIES

TX...None. GM...None.