textproduct: Houston/Galveston

KEY MESSAGES

- High rainfall rates today will result in minor flooding of poor drainage areas as well as a risk for isolated to scattered flash flooding.

- Look for increasing winds/seas/rip current risk along the coast through Monday.

- Decreased rain chances and increasing heat risk are expected through the coming week.

DISCUSSION

Issued at 1223 PM CDT Sat Jun 6 2026

Scattered to numerous showers with a few thunderstorms are currently developing with daytime heating and onshore low-level flow, downstream of an upper low over the Texas Panhandle. There's been little change in the tropical air mass over the area with saturated profiles, PWATs of 2-2.2", and high freezing levels. This will once again be favorable for efficient/high rainfall rates of 2-3" or more per hour. 500mb flow around 25-30kts will keep cells moving, and there isn't any particular focusing mechanism, but uni-directional 850-500mb flow may allow localized training. 12z HREF guidance continues to indicate potential for localized 3-4"+ amounts. This combined with recent heavy rainfall/lower flash flood guidance will result in the potential for street flooding and rises on streams and bayous, along with isolated to widely scattered flash flooding. A level 2 out of 4 (slight risk) of excessive rainfall remains in effect. Activity should diminish this evening, though a few isolated showers may develop overnight given the moist air mass.

By Sunday the upper low will open up into a shortwave trough and lift northeastward towards Kansas and Missouri. An upper-level jet streak will remain across southeast Texas, with a mid-level shear axis getting left behind as well. PWATs will remain near 2 inches with high low-level moisture, but some drier air aloft will move in as well. A decrease in coverage of showers and storms is expected, more in the isolated to scattered range. Some isolated heavy rainfall rates will remain possible with any storms. Any stronger storms that do get going would also have a bit more potential for gusty winds than previous days due to the dry air aloft/DCAPE and an uptick in mid-level lapse rates.

Mid-level ridging builds over the south-central CONUS and western Gulf Monday through the rest of the week. This ridging combined with drier air aloft will result in a decrease in coverage of diurnal convection. However, with continued hot and humid conditions, onshore flow, and the sea breeze, rain chances will not go to zero. Some adjustments to PoPs will probably occur as we get closer. Heat indices will be mainly in the 100 to 107 range, though a few spots may be near 108 by the end of the week. Heat Risk will mostly be in the "moderate" category, though later in the week a few patches of Heat Risk in the "major" category begin to show up.

JDavis

AVIATION

(00Z TAF Issuance) Issued at 624 PM CDT Sat Jun 6 2026

Today's shower and thunderstorm activity has largely ended with just some isolated showers lingering through sunset. The region should be rain-free through tonight, though cannot out rule an isolated storm moving into CLL from the NW late tonight into early tomorrow morning. Scattered showers and thunderstorms are again expected to develop across much of the area by the late morning through the afternoon. Conditions are a bit more unfavorable for TS development compared to the past couple of days, but an isolated storm is still expected. At this time, due to confidence levels and expected level of coverage, have gone with VCSH with PROB30 of TS for much of the area tomorrow between 16-22z.

VFR conditions will continue through this evening, but moist low- levels will bring MVFR conditions to the region by 3-5z with low- end MVFR to high end IFR (700-1200ft) CIGs possible late tonight into early tomorrow morning for most terminals except the coast (GLS and LBX). VFR conditions are expected to return by the late morning on Sunday. Winds will be SSE around 5-8kt overnight, and then 8-12kt during the day on Sunday (with gustier winds near any developing thunderstorms).

Fowler

MARINE

Issued at 1223 PM CDT Sat Jun 6 2026

Persistent onshore flow continues for the coastal waters for the weekend and much of next week. Winds will remain southeasterly at around 10 to 15 knots but will increase to 15 to 20 knots late tonight into early tomorrow. Small craft exercise caution flags have been issued for tonight into Sunday afternoon, and will likely be needed for Sunday night as well. Seas will be around 2 to 4 ft, as high as 5 ft in the far offshore waters. Isolated showers and storms will remain possible at times, with the relatively highest chances near the bays today.

JDavis

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 74 87 76 90 / 10 30 0 20 Houston (IAH) 76 88 78 90 / 30 30 10 10 Galveston (GLS) 82 88 82 88 / 20 10 20 10

HGX WATCHES/WARNINGS/ADVISORIES

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

GM...Small Craft Should Exercise Caution from 10 PM CDT this evening through Sunday afternoon for GMZ330-335-350-355-370-375.