Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
Issued by NWS Houston/Galveston, TX
603 FXUS64 KHGX 192343 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 543 PM CST Wed Nov 19 2025 ...New AVIATION... .KEY MESSAGES... - Near record warmth will continue areawide for the next few days. - Rain chances increase late Thursday and Friday as the next weather system approaches from the west and drags a weak frontal boundary into the region. Rain chances linger into the weekend. - Another system is expected to enhance shower and thunderstorm activity on Monday. && .DISCUSSION... Issued at 1209 PM CST Wed Nov 19 2025 A mid/upper low over SW CONUS and NW Mexico will push eastward as its structure transitions from a closed low to a negatively tilted trough. A strong, diffluent southwesterly jet ahead of the the low is evident over a large region spanning south-central CONUS, SW CONUS, and much of northern Mexico. Plentiful mid/upper moisture from the tropical / subtropical Pacific is being advected north to northeast by the jet. This mid/upper level moisture advection coupled with rising LL PWATs is resulting in an increasingly moisture rich atmospheric profile. We are already seeing isolated to widely scattered showers on radar this afternoon. We suspect this shower activity will continue through the day. However, many neighborhoods will remain dry. Lift and sheer will gradually increase as the trough ejects east to northeast, resulting in a corresponding increase in PoPs on Thursday and especially Thursday night into Friday as a sfc front pushes across the region. Given the shear and moisture parameters, locally heavy showers and thunderstorms cannot be ruled out late Thursday through Friday, especially along the weakening frontal boundary. That being said, the jet will be most diffluent over central and northern Texas. Therefore, the best chance of heavy rainfall and isolated strong to severe thunderstorms will be north and west of our region. Best chance of localized flash flooding in our region will be across our northern counties. The front stalls and becomes increasingly diffused over the weekend. However, it may provide enough lift for some scattered activity on Saturday and maybe Sunday, especially near where the front stalls. Another mid/upper low/trough is expected to enter the picture late Sunday into Monday. Current guidance suggest a similar set up, with the heaviest weather to our north and west despite a decent chance of scattered activity for SE Texas. A little too early to assume that this second system will be just like the first. But the signal suggests it will be similar. May have to keep an eye on the rivers if enough rainfall occurs to our north. But the drought conditions will be a mitigating factor. Now let`s talk about temperatures. We are expecting near record warmth areawide through Thursday, and across the southern half of the CWA through Friday. This translates to highs well into the 80s. Coupled with the humidity, the air will entail a more summer-like vibe. Warm, but not the near record warmth of late, is expected Sunday and Monday, with most areas expected to be in the upper 70s to low 80s. Beyond then, the pattern may go into flux. Current large scale teleconnections are strongly supportive of a warmer pattern. But those signals are expected to become more mixed as we head into next week. In addition, global deterministic and ensemble guidance suggest the end of the current split-flow jet pattern and the beginning of a more polar jet dominant pattern. This would support stronger cold fronts pushing southward into CONUS. Global models are hinting at a possible strong cold front by the end of November or early December. But the globals can be wrong. Generally speaking, I`d say the signals are supportive of temperatures dropping to near normal (highs in the 70s, lows in the 50s) by the middle of next week. Self && .AVIATION... (00Z TAF Issuance) Issued at 543 PM CST Wed Nov 19 2025 VFR conditions and southeasterly to southerly winds will prevail through the evening hours. Expecting another round of decreased visibilities and cloud ceilings overnight with conditions varying between LIFR to MVFR areawide. The window the best potential for LIFR conditions looks to be between 09Z-14Z. Conditions will gradually improve through Thursday morning with improvement to MVFR for a few hours before VFR conditions return by 18Z. Also around 18Z is when southerly winds are expected to become gusty with sustained winds around 8-12 kt with gusts up to 20-25 kt through the afternoon. Some sporadic rain showers will be possible Thursday as well, but confidence on the exact timing and location is on the low side at this time. Through the afternoon, the best potential will be east of I-45. The greater confidence on rain comes near or just after the current period of this TAF package as a frontal boundary pushes into the region late Thursday night into Friday morning. Expect another round of decreased ceilings and visibilities going into Thursday night as well. Batiste && .MARINE... Issued at 1209 PM CST Wed Nov 19 2025 Generally light to moderate onshore flow and 2-4 foot seas are expected through the weekend. Winds could become more variable on late Friday into Saturday if a frontal boundary makes it far enough south. Isolated to widely scattered showers/thunderstorms possible today and tomorrow, with a better chance on Friday and Saturday as a weakening frontal boundary makes its closest approach from the north. Onshore flow may increase enough to warrant caution flags on Monday into early Tuesday ahead of the next system that will bring another enhanced chance of showers and thunderstorms. Winds are expected to shift northwesterly on Tuesday as a cold front pushes offshore. At this time, the front does not appear as strong as recent fronts that produced impactful winds and seas. But we cannot rule out caution flag worthy winds beyond the front on Tuesday. && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 69 85 67 79 / 20 50 70 70 Houston (IAH) 69 85 70 85 / 10 20 30 60 Galveston (GLS) 71 78 71 80 / 10 30 20 50 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ DISCUSSION...Self AVIATION...Batiste MARINE...Self