FXUS64 KHGX 042321 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 621 PM CDT Fri Sep 4 2026 ...New AVIATION... .KEY MESSAGES... - Scattered afternoon showers and thunderstorms are expected through early this evening. Locally heavy rain, resulting in minor flooding and gusty conditions are the main risks with the strongest storms. - A daily risk of isolated to scattered showers and thunderstorms are expected this weekend and will persist into next week. - Hotter and humid conditions return to the region with heat indicies in the triple digits each day. && .DISCUSSION... Issued at 115 PM CDT Fri Sep 4 2026 Radar has blossomed early this afternoon with scattered showers and thunderstorms developing over the coast and slowly moving/training inland. Atmospheric profiles and observations show deep low to mid level moisture still remaining over the region with PWATs in the 2 - 2.4 inch range. In addition, there are a few mid-level vorticity maxes moving overhead as a surface a trough extends along the coast. This dynamic combined with peak daytime heating and seabreeze interaction will be enough to maintain rain and storm chances across the region this afternoon. The primary risk with these storms will be localized flooding, gusty winds and frequent lightning. This activity should gradually diminish around sunset with the loss of daytime heating. While we will get a lull in precipitation this evening, rain and storm chances return late tonight through early Saturday evening. Forecast soundings show a very moist profile with PWATs still at or above 2.0 inches through the weekend. The pattern won't change much with a mid to upper level low spinning across the Gulf, weak surface troughs developing over the waters and a few impulses of energy moving overhead. Overall, this pattern will be enough to keep rain and storm chances around 30 to 70%, particularly in the afternoon hours as the seabreeze kicks in. A mid to upper lvl ridge expands over the Plains, with the axis moving over the Southeast Texas Sunday into early next week. This will bring back hotter and more humid conditions. While subsidence aloft will influence the pattern locally a bit, the region will be positioned on the southeastern fringe of the ridge, bringing weak vort maxes embedded in the flow aloft. Again, this pattern along with increased Gulf moisture and seabreeze interaction will be enough to support daily rain and storm chances, mostly over the coast in the morning, then spreading further inland in the afternoon and early evening. Temperatures will generally remain near to slightly above average for this time of year. Highs will generally be in the low to mid 90s, with the warmest readings for our far western counties. Heat indices will be in the 102 to 109F range, with the warmest conditions expected next week. JM && .AVIATION... (00Z TAF Issuance) Issued at 620 PM CDT Fri Sep 4 2026 Lingering -RA/-TSRA should diminish within the next hour or so. Otherwise, winds will gradually become light and variable from this evening and overnight through late Saturday morning. Some models are hinting at some low ceilings approaching from the northeast with areas of fog, potentially impacting KUTS and KCXO around sunrise. Another day with scattered SHRA/TSRA is anticipated, with most of the activity developing in the east, and moving west-southwest across the entire region throughout the day. Confidence in rain/storm chances is moderate to high; however, confidence in the timing and the exact locations of the heaviest precipitation remain low to moderate. Therefore, will continue with VCSH and PROB30 for this set of TAFs, until we get better agreement from the Hi-Res models in future TAF issuances. Overall, expect the best chance of rain and storms in the afternoon through the early evening hours (17Z Saturday - 02Z Sunday). Outside of any storms and morning low clouds across the far northern terminals, VFR conditions will prevail. JM && .MARINE... Issued at 115 PM CDT Fri Sep 4 2026 Weak disturbances over the Gulf will continue to bring a daily risk of isolated to scattered showers and thunderstorms across the Upper TX coast this weekend and into the upcoming week. Otherwise, light to occasionally moderate onshore winds and seas into the 2 to 3 ft range will prevail through late next week. JM && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 74 96 74 95 / 20 30 10 30 Houston (IAH) 78 93 77 93 / 10 60 20 70 Galveston (GLS) 82 90 81 90 / 30 40 50 50 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ DISCUSSION...JM AVIATION...JM MARINE...JM