Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
Issued by NWS Houston/Galveston, TX
072 FXUS64 KHGX 050513 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 1213 AM CDT Fri Sep 5 2025 ...New KEY MESSAGES, DISCUSSION, MARINE... .KEY MESSAGES... Issued at 1200 AM CDT Fri Sep 5 2025 - Another hot day today with only a few isolated showers and storms over the coast. - Increasing humidity on top of today`s hot temperatures will lead to heat index values peaking in the 102-106F range - Rain chances return over the weekend and into early next week as moisture increases ahead of a frontal boundary. - Hot days but comfortable nights are expected late this weekend into the middle of next week after the passage of a cold front. && .DISCUSSION... Issued at 1200 AM CDT Fri Sep 5 2025 Summer heat continues today, and you will feel more humidity. Surface high pressure to our east will continue to bring southerly warm and more humid air overnight and through the day. Increasing moisture will also bring more cloud cover and highs in the mid to upper 90s. It will feel even hotter with peak afternoon heat indices close to 102 - 107F. With increasing low-level moisture, cannot rule out isolated showers or storms popping up over the coast and along the seabreeze. From hot and dry conditions, we will transition to a more active pattern with isolated to scattered showers and storms over the weekend into early next week. A gradual increase in moisture is expected at the surface from the Gulf and at mid to upper levels due to the remnants of Tropical Storm Lorena. Although, latest guidance have trended a bit drier as Lorena shifts slightly westward and weakens within the next 24 hrs; we will still see an uptick in tropical moisture aloft. Given the latest forecast of Lorena, it is uncertain the extent of moisture across SE TX. However, forecast soundings keep suggesting increasing mid to upper-level moisture after Saturday, and this will be enough to support isolated to scattered activity through the weekend. Overall, for Saturday, isolated to scattered showers and storms are expected ahead and along and approaching cold front from the north, and further south (close to the coast) along the sea/baybreeze. The best rain/storm chances arrive Sunday into Monday with the combination of the FROPA, increasing moisture, and passing shortwaves aloft. Confidence in time of arrival of front and the location of the heaviest rainfall and hence, total rainfall amounts still remains moderate. As of now, we are not anticipating a complete washout, but pockets of moderate to heavy rain can be anticipated. WPC keeps highlighting this risk with a Marginal Risk (level 1 of 4) of excessive rainfall for all southeast TX Sunday into early Monday. A drier airmass will gradually filter in from the northwest early next week. However, the frontal boundary will become quasi- stationary along the coast or just offhsore through most of the upcoming week. This boundary will serve as the main focus for showers and storms. Therefore, will continue with a relatively dry forecast inland, but with chances of rain/storms along the coast. Near to slightly below normal temperatures are expected Sunday into mid-week as the boundary meanders near the region. This will result in comfortable overnight lows further inland. Lows will generally remain in the low 60s to mid 70s most of the upcoming week. JM && .AVIATION... (00Z TAF Issuance) Issued at 548 PM CDT Thu Sep 4 2025 VFR conditions will generally persist through the period, although there may be a brief period of patchy fog at SGR and CLL during the predawn hours on Friday. Light, variable winds will continue through this evening and into early Friday morning with south to southeasterly winds developing by the mid to late morning around 10kt. These winds will persist through sunset before becoming predominately light and variable again. Fowler && .MARINE... Issued at 1200 AM CDT Fri Sep 5 2025 Fair marine conditions continue today with light to occasionally moderate onshore winds and low seas. A few/isolated showers and storms cannot be ruled out along the coast, especially along the sea breeze later this afternoon. The best rain and storm chances arrive this weekend ahead of an approaching cold front. This boundary will move near the coast on Sunday, potentially stalling along the coast or over the Gulf waters through early next week. So, rain chances will continue through next week near this stalled boundary. Moderate winds and seas up to 3-4 ft can be expected early next week as the front moves through the waters. JM && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 75 89 72 87 / 10 40 20 60 Houston (IAH) 77 93 75 89 / 0 30 20 60 Galveston (GLS) 82 90 80 89 / 10 30 30 50 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ DISCUSSION...JM AVIATION...Fowler MARINE...JM