textproduct: Houston/Galveston

KEY MESSAGES

- Moderate heat risk will continue today and persist each day through Thursday. Peak heat index values between 102-107F (39-42C).

- Moderate to major heat will be possible Friday and into the Fourth of July weekend. Peak heat index values between 105-110F (40-43C).

DISCUSSION

Issued at 132 PM CDT Tue Jun 30 2026

Our main weather driver is a mid-level high ridge that has now centered itself across the ECONUS placing southeast Texas on the southwestern periphery of this ridge. With the ridge now shifted to the northeast, this has allowed for PWATs to increase to 1.5" to 1.7" today. Weak impulses on the periphery of this ridge have been enough to produce streamer showers earlier this morning. While these showers have moved inland, they have kept their overall strength resulting in locations generally west of I-45 seeing up to 0.25" of rainfall. These showers are moving along keeping rainfall amounts isolated and light.

PWATs peak on late Wednesday and Thursday to near 2.00" right at the same time that a few weak disturbances round out the periphery of the ridge allowing for the daily convection and seabreeze storms to have more moisture to wring out. The focus for Wednesday afternoon's rain chances (20-30%) will be greatest closer to the Golden Triangle, though there is lower confidence across the Houston metro. We will continue to monitor CAM guidance to see if PoPs need to be increased with the next forecast package. By Thursday, overall rain chances increase to (30-50%) across the Piney Woods, across the Houston metro, and towards Matagorda Bay. Much like with the previous forecast package, if this plume of higher PWATs ends up moving more closer to the Houston metro, then rain chances may need to be further increased. We will continue with these afternoon convection/seabreeze storms through the Fourth of July weekend. While not a complete washout of a forecast if you're planning for outdoor activities, it would be prudent to have an alternate plan for a short period while a shower moves through.

The HeatRisk will continue to be the main threat outside of rain chances. Peak heat index values range between 102-107F (39-42C) with values increasing to 105-110F (40-43C) for this weekend. The highest values will likely be observed in locations that do not see a seabreeze shower move overhead. We continue to monitor the forecast trend to see if Heat Advisories may be needed for the holiday weekend. Frequent hydrating and shade/AC breaks will be key to beating the heat.

With respect to the rip current threat, the high rip current risk has been allowed to expire. With lower wave periods moving in, the risk drops to a moderate risk, but we will continue to re- evaluate this overnight for any additional issuances.

AVIATION

(00Z TAF Issuance) Issued at 647 PM CDT Tue Jun 30 2026

Persisting VFR conditions throughout this evening in most regions. Included TEMPO of low level stratus forming tonight around College Station, Huntsville, and Conroe which may bring patchy MVFR conditions around 9Z-13Z. Winds will remain from the southeast and will weaken tonight to around 5kt. Tomorrow morning winds can be expected to pick back up, sustaining around 5-10kt with gusts of 18kt by the afternoon.

Wingo/Bailey

MARINE

Issued at 132 PM CDT Tue Jun 30 2026

Gentle to moderate breezes will vary from a southerly to southeasterly direction with 2-3 ft seas along with daily chances for scattered showers/thunderstorms, primarily over the nearshore waters and bays.

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 76 95 76 94 / 10 0 0 10 Houston (IAH) 78 95 78 94 / 0 10 10 30 Galveston (GLS) 83 89 82 89 / 0 0 10 10

HGX WATCHES/WARNINGS/ADVISORIES

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