Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
Issued by NWS Houston/Galveston, TX
753 FXUS64 KHGX 031150 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 650 AM CDT Wed Sep 3 2025 ...New AVIATION... .KEY MESSAGES... Issued at 1148 PM CDT Tue Sep 2 2025 - Drier conditions are expected the rest of the week with only a few isolated activities mainly along the coast. - Hot weather with low humidity can be expected mainly on Thursday and Friday with highs in the mid to upper 90s. - Rain chances return over the weekend and into early next week as moisture increases ahead of a frontal boundary. && .DISCUSSION... Issued at 1148 PM CDT Tue Sep 2 2025 After a few days of daily rain and storm chances, a dry pattern is setting up, at least through the end of the workweek. Latest Blended Total Precipitable Water satellite imagery and surface obs show a gradual decrease in PWs this evening from the NW, suggesting a drier airmass beginning to filter in. However, some moisture will still persist over the coastal counties on Wednesday, resulting in isolated showers and storms. With high pressure persisting over us, the overall trend is for much lower rain chances and coverage than previous days. Low rain chances lead to mostly sunny skies and hence warmer conditions. Deterministic models show 850mb temperatures climbing into the 20 to 24 degC. These values are in the 97.5th to 99th percentile of climatology based on NAEFS and GEFS, particularly for areas west of I-45. Given that, high temperatures will rise through the week, climbing back into the mid to upper 90s Thursday and Friday. With a drier airmass in place, it is not expected to be as humid, so it will be a dry heat. Heat indices at or exceeding 100F can be expected in the afternoon. It is important to continue practicing heat safety, especially during the peak of daytime heating. The weather pattern changes this weekend into early next week with increasing rain and storm chances. Winds will transition more to the south-southeast by Friday, bringing a warmer airmass and more Gulf moisture further inland. While precipitation chances will remain low on Friday; a broad area of theta-e advection will suggest an increasing cloud cover over the region. The main weather-maker will arrive over the weekend ahead of an approaching frontal boundary from the north. We`re monitoring not only the boundary but a possible surge of Pacific/tropical moisture filtering in at the same time. This tropical moisture is most likely associated with Tropical Storm Lorena over western Mexico. The combination of tropical moisture, a few mid-level shortwaves, and this approaching front could lead to rounds of moderate to heavy rain across SE TX late this weekend and early next week. It is too early to pinpoint the exact timing and location of the heaviest rain as it will depend on the track/intensity of the Pacific tropical moisture and the front. As of now, will continue with increasing rain and storm chances Saturday into Tuesday. JM && .AVIATION... (12Z TAF Issuance) Issued at 647 AM CDT Wed Sep 3 2025 KCXO at MVFR with VSBYs. All other sites at VFR. VFR prevailing through the day. Winds will be light out of the NNE through the morning, becoming ENE this afternoon. && .MARINE... Issued at 1148 PM CDT Tue Sep 2 2025 Benign marine conditions with light winds (generally around 5 to 15 knots) and low seas (1 to 2 ft), will continue at least through early this weekend. Rain and storm chances will be on the increase over the weekend and into early next week as tropical moisture increases ahead of another frontal passage over the region. Moderate winds and seas can be expected early next week. JM && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 92 68 97 73 / 10 0 0 0 Houston (IAH) 93 74 96 75 / 20 0 0 0 Galveston (GLS) 90 80 91 82 / 20 20 0 0 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ DISCUSSION...JM AVIATION...Adams MARINE...JM