Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
Issued by NWS Houston/Galveston, TX
840 FXUS64 KHGX 262336 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 636 PM CDT Sat Jul 26 2025 ...New AVIATION... .KEY MESSAGES... Issued at 104 PM CDT Sat Jul 26 2025 - Scattered showers and storms are expected through early this evening. Locally heavy downpours and gusty winds will be possible with the stronger storms. - Beginning next week, the focus will be heat and humidity, with the potential of heat advisories by mid-week. - Whether or not an advisory is issued, those individuals who are vulnerable to heat, or will need to exert themselves strenuously outdoors should have a plan to stay ahead of heat illness this week. - Later in the week, another surge of tropical moisture will increase rain and storm chances. && .DISCUSSION... Issued at 104 PM CDT Sat Jul 26 2025 Deep Gulf moisture associated with a decaying surface trough remains over the region today. Latest satellite imagery and surface observations show PW values in the 2.1 to 2.5 inch range over the entire region. In addition to abundant moisture, weak forcing aloft along with surface frontogenesis developing along the coast are also contributing to the development of showers, a few locally heavy and thunderstorms this afternoon. As the afternoon progresses, showers and storms will continue to spread inland from the coast. Again, daytime heating along with significant moisture remaining over us could potentially lead to locally heavy rain, resulting in ponding on roads and minor street flooding, especially in areas with saturated grounds. Gusty winds up to 40 mph cannot be ruled out with the strongest storms. Rainfall totals less than an inch can be expected, though pockets of 1 to 3+ inches will be possible with the strongest cells. Rain and storms will gradually diminish this evening from south to north, followed by a muggy and warm night. Sunday will feature coastal showers early in the morning, spreading inland by mid-late morning. Scattered storms are expected in the afternoon, though with potentially less coverage than Saturday. We`re heading towards a more typical late July pattern with relatively drier and hotter conditions for the upcoming week. A high pressure system currently to our east will shift westward and build over the region late Sunday into Monday. This pattern will bring a drier airmass, and hence more stable conditions dominating southeast TX. Lingering low-level moisture surging inland from the Gulf will still lead to isolated coastal morning showers and inland afternoon storms at least on Monday. The main weather story will be hot and humid conditions. Highs will gradually climb into the mid to upper 90s by mid-week. Peak heat indices in the triple digits can be expected. Will continue to monitor trends as we might be close to advisory levels by mid-week. Deja vu? Another surge of tropical moisture is expected to arrive towards the end of the work-week as a mid-level trough slides across the southeastern CONUS/northwestern Gulf. While specific details and timing of this trough are still uncertain; this impulse of moisture will bring increasing rain and storm chances Thursday into the weekend. JM && .AVIATION... (00Z TAF Issuance) Issued at 627 PM CDT Sat Jul 26 2025 VFR at all terminals this evening. MVFR CIGs projected to return overnight for northern terminals, becoming VFR shortly after sunrise on Sunday. Showers and thunderstorms return to the area Sunday afternoon, though less coverage expected compared to Saturday`s storms. Maintained PROB30 from 18Z-22Z for IAH and southern terminals. Winds remain generally light with a southerly component. Winds may become gusty and variable with any thunderstorms. && .MARINE... Issued at 104 PM CDT Sat Jul 26 2025 Surface high pressure to our east remains in control. However, deep Gulf moisture will continue to support showers and thunderstorms, at least through today and Sunday. Therefore, expect scattered to numerous activity through the day with some embedded strong storms possible at times. These strong cells will be capable of producing heavy downpours, lightning, and gusts reaching or exceeding 30 knots at times. Going into next week, high pressure will shift westward towards our region, resulting in drier and hotter conditions for most of the week. Light onshore winds and seas can also be anticipated with a typical summertime pattern of landbreeze (offshore winds at night) and seabreeze (onshore winds during the afternoon). JM && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 75 94 74 96 / 10 20 0 0 Houston (IAH) 78 92 77 96 / 10 50 0 20 Galveston (GLS) 84 91 84 91 / 10 50 0 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...High Rip Current Risk until 9 PM CDT this evening for TXZ436>439. GM...None. && $$ DISCUSSION...JM AVIATION...Adams MARINE...JM