textproduct: Houston/Galveston

KEY MESSAGES

- Wet weather will resume through the end of the workweek into Mother's Day weekend with an isolated flash flood threat before drier days return early next week.

- Areawide rainfall totals of at least 1 to 2 inches (with locally higher amounts) are likely through the end of the day on Saturday.

- After Sunday's frontal passage delivers another chance of rain (30-50%), mostly drier and warmer weather is expected into the middle of next week.

DISCUSSION

Issued at 1156 PM CDT Thu May 7 2026

The synoptic arrangement behind this weekend's wet start involves: a persistent mid-level trough approaching West Texas early on Friday, a broad ridge axis across the Gulf, and a stationary frontal boundary offshore. More near-term guidance/CAMs are beginning to resolve convective modes and distributions, however, forecast uncertainty remains the most elevated for the these two aforementioned convective characteristics. Forecast certainty is increasing on a more isolated and conditional flash flood threat with the threat condition hinging strongly upon the location and rate of the heaviest rainfall (impervious surfaces are especially at risk) through Saturday. Above average forecast PWAT values ranging at 1.75-1.9 inches (well above the 75th percentile for this time of the year), and deep cloud layers will all add up to maintain a mostly favorable environment for efficient rainfall production. What keeps this flash flood threat from becoming more serious for southeast Texas involves relatively fast up/downshear vectors (over 15 kts.), and fast LCL-EL cloud layer winds reflected in forecast soundings that will aid in the progression and distribution of convective downdrafts.

The last round of rainfall is expected with the frontal boundary proceeding swiftly through the area later on Sunday and influencing some compressional heating along the way. The temporal window for the wet weather will begin to close by Monday for a drier start to the workweek as ridging gradually displaces northwesterly flow through the week. Temperature maximums/minimums will respond in kind (upper 80s/lower 70s, respectively) by the end of the week.

Cassel

AVIATION

(00Z TAF Issuance) Issued at 552 PM CDT Thu May 7 2026

Most terminals are VFR this afternoon, but MVFR ceilings continue to persist along the coast. Northerly to northeasterly winds around or less than 10 kt will become light and variable this evening as MVFR ceilings gradually spread inland. Intermittent periods of IFR ceilings cannot be ruled out along the coast after 12Z/Friday. Scattered showers are expected to move through the area generally between 10Z-17Z. There is potential for convection in the late morning to early afternoon hours on Friday, but confidence is on the low side as model guidance is very inconsistent on the timing and placement of convection. Winds on Friday will be on the light side, but will start out easterly in the morning and becoming east-southeasterly in the afternoon. MVFR ceilings are expected to linger throughout the day, but there is potential for VFR to return in the afternoon. Either way, expect MVFR to IFR ceilings fill back in again Friday evening along with increasing chances for showers/storms.

Batiste

MARINE

Issued at 1156 PM CDT Thu May 7 2026

With a stationary front remaining just offshore, a 30-50% chance of thunderstorm development will continue through the next 48-72 hours carrying the threat of locally strong downdrafts. Medium- range guidance suggests another chance of somewhat elevated post- frontal northerly winds offshore by Monday that return back onshore by Wednesday. These post-frontal winds are expected to remain below the threshold requiring issuance of a Small Craft Advisory at this time.

Cassel

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 63 78 68 82 / 10 30 30 50 Houston (IAH) 67 78 71 84 / 10 50 40 40 Galveston (GLS) 73 80 75 82 / 20 50 30 40

HGX WATCHES/WARNINGS/ADVISORIES

TX...None. GM...Small Craft Should Exercise Caution until 1 AM CDT Friday for GMZ335-350-355-370-375.