Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
Issued by NWS Houston/Galveston, TX
349 FXUS64 KHGX 171844 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 1244 PM CST Mon Nov 17 2025 ...New DISCUSSION, MARINE... .KEY MESSAGES... - Unseasonably warm weather (near record temperatures) will persist through midweek. - Periods of late night and early morning fog possible on a daily basis. - Rain chances remain minimal through Tuesday, then increase Wednesday into Thursday ahead of an approaching disturbance. A cold front is expected to reach the area late Thursday, bringing a stronger round of showers and thunderstorms. && .DISCUSSION... Issued at 1029 AM CST Mon Nov 17 2025 Increasing moisture from the onshore flow has lead to mostly cloudy skies across SE Texas this morning, and even some light spotty showers popping up across the area. These showers may produce a brief sprinkle, but otherwise we will remain rain-free through Tuesday. The near record warmth will continue through midweek with high temperatures in the mid to upper 80s across much of the area with overnight lows in the mid 60s to low 70s. We will be entering a bit of a pattern change starting on Wednesday. The upper-level high pressure that has been over Texas the past few days will begin to be shoved eastwards over the Gulf as an upper-level low swings through the Desert Southwest. We will likely see some isolated showers during the day on Wednesday from the increasing moisture and the decreasing subsidence from the exiting high pressure with the best chances across the Brazos Valley and Piney Woods region where passing weak upper-level shortwaves may help support activity. Increasing WAA from the strengthening southerly winds and PVA from the approaching disturbance to the west will allow for scattered showers and isolated thunderstorms across the region on Thursday. The activity during the day on Thursday is looking fairly light, but some moderate rainfall is possible with any thunderstorms. Activity is expected to increase heading into the evening and overnight hours Thursday as the cold front associated with the disturbance moving in from the west, though the exact FROPA timing is uncertain at this time. As the front slides through the area, there will likely be an increase in shower and thunderstorm activity ahead of and along the front itself. There is potential for some locally heavy rainfall as the front slides through the area, with WPC placing parts of the Piney Woods and Brazos Valley in a Marginal Risk (level 1 of 5) for excessive rainfall for Thursday and areas along and east of I-69/US-59 for early Friday morning. We are quite dry across the region with 3-hr FFG ranging from 4-6", so the most likely impact from any heavy rainfall will likely just be some minor ponding in areas of poor drainage. There will also be the potential for some isolated strong thunderstorms to pop-up ahead of and develop along the cold front. However, the trend has continued to be for less instability for thunderstorms to work with (a combination of activity during the day on Thursday keeping the instability low overnight, and the loss of daytime heating with the FROPA occuring overnight). Still, if thunderstorms are able to develop overnight, there will be a chance for one or two strong (to maybe severe) thunderstorms. Details on this threat will become between known once we are within 72-hours of the event. Forecast confidence remains very low after the front moves into/through the area. Guidance is split on whether the front either stalls near the coast Friday night through the weekend (thus keeping a chance of showers for at least areas south of I-10), or if it clears the region before stalling out in the central Gulf (thus bringing drier air into the region). While the cold front will bring cooler air to the region, the airmass behind the front is more Pacific-based rather than Artic-based. And without a strong temperature gradient across the FROPA, I am leaning more into the first solution where the front stalls near the coast. So at this point, I kept a slight chance to a chance of showers over the weekend, but this may change in the coming days. Fowler && .AVIATION... (12Z TAF Issuance) Issued at 518 AM CST Mon Nov 17 2025 A wide range of conditions across SE TX this morning, but (very) generally speaking, it`s more IFR/low MVFR inland, and MVFR to IFR closer to the coast. Winds have kept up somewhat through the night, so we trend more towards CIGs from low stratus being the limiting factor, but fog to 1SM (or less!) does seem to pop up in localized spots where winds go slack. So...the toplines at all sites do my best to reflect obs, while allowing for some degradation briefly, mainly through TEMPOs. Those TEMPOs may be somewhat pessimistic, but should reflect a plausible worst case that could briefly occur within a couple hours of sunrise. Of course, as the morning goes on, conditions should improve markedly, with widespread VFR and south winds around and just on the high side of 10 knots with some gusts to around 20 knots. Guidance strongly suggests winds stay up again overnight, so similar to now, I go more aggressive with CIGs and have backed off with VSBY restrictions except at those spots that tend to fog up more readily (looking at you, LBX). && .MARINE... Issued at 1029 AM CST Mon Nov 17 2025 Light to occasionally moderate onshore flow and seas 2-4ft will persist through early Wednesday. There will continue to be a slight chance for nightly patchy fog in the northern parts of the bays through Tuesday night, but increasing southerly flow on Wednesday will likely bring the end to those slight chances. An approaching disturbance from the west will cause moderate onshore winds late Wednesday night through Friday morning. Guidance has decreased slightly on the wind speeds during this timeframe to be around 15-20kt with gusts to 25kt possible with seas around 4-6ft. Small craft will likely need to exercise caution during these conditions, and a Small Craft Advisory is possible if those gusts become frequent enough. Isolated to scattered showers and storms are expected during the day on Thursday, but there will be increased chances overnight Thursday into Friday morning with the passage of a cold front. There is uncertainty on how far off the coast this front will make it before slowing down/stalling. It is possible it may linger along the coast through the weekend keeping a chance of showers or storms in the forecast. Fowler && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 69 86 66 85 / 10 10 10 40 Houston (IAH) 68 87 68 85 / 0 0 10 20 Galveston (GLS) 71 80 71 79 / 0 0 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ DISCUSSION...Fowler AVIATION...Luchs MARINE...Fowler