Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
Issued by NWS Houston/Galveston, TX
464 FXUS64 KHGX 041120 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 620 AM CDT Fri Jul 4 2025 ...New AVIATION... .KEY MESSAGES... Issued at 1205 AM CDT Fri Jul 4 2025 - Hit-or-miss showers with thunderstorms are expected for the 4th of July with the best chances in the afternoon. Some lingering showers will persist across some areas, but overall, chances should diminish by early evening... just in time for fireworks. - A thin plume of Saharan dust still remains over the region, resulting in hazy skies through at least late Saturday. - A daily risk of showers and storms can be expected next week. - Hotter conditions return after mid-week, with highs mainly in the mid to upper 90s. && .DISCUSSION... Issued at 1205 AM CDT Fri Jul 4 2025 Southeast Texas (and basically the entire southern Plains) remain largely under the influence of a persistent upper-level ridge, which typically promotes warm and relatively dry conditions. However, the atmospheric pattern is not entirely "tranquil", as multiple mid- level (around 700-500 mb) shortwaves are actively traversing the region. In addition, a robust highway of deep tropical moisture continues to advect inland. This influx of moisture is noteworthy with PWATs observed to be in the 1.9 to 2.2 inch range. These values are near the max of climatology for this time of year, indicating and exceptionally humid airmass. The combination of these shortwaves, providing dynamic lift, and the abundance of tropical moisture is creating a favorable environment for showers with a few storms. This trend will continue for the 4th of July as the main ridge shifts westward and more shortwaves move overhead. Therefore, light rain will continue early this morning, becoming more scattered and potentially yielding a few thunderstorms in the afternoon. Rain and storms should gradually diminish by early evening as the main shortwave moves out of the region. A few areas could still see some lingering showers early in the evening, but overall, chances should diminish just in time for fireworks. As we head into the weekend, rain chances will be lower but non- zero. Ridging aloft slightly shifts westward, as a sfc high builds over the Gulf. As mentioned before, different vorticity maxes (shortwaves) will continue to develop on the nose of a weak LLJ across central TX. This will keep slight rain chances across the region, especially west of I-45. In terms of temperatures, with more cloud breaks and less precipitation chances, Saturday looks hotter. Highs will generally be in the low to mid 90s. A mid-level trough is progged to develop along the northwestern Gulf on Sunday, slowly moving towards the Upper TX coast by Monday. Sufficient moisture and increasing PVA with heights will support rain and storms during this time-frame. At the moment, the best precipitation chances look to be for the coastal zones. After mid- week, ridging to our west strengthens while a sfc high builds over the western Gulf. This pattern will bring a gradual warming trend with highs in the mid to upper 90s. A daily risk of rain and storm chances is also anticipated for the rest of the week, especially during the afternoon...typical summer weather pattern. JM && .AVIATION... (12Z TAF Issuance) Issued at 548 AM CDT Fri Jul 4 2025 Cloud decks currently around 1800-2500ft across the area with LIFR CIGS to the northwest at KCLL. Decks may fill in over the next few hours to bring brief MVFR conditions at KIAH and northward. All CIGs should clear/lift later this morning with VFR conditions mostly prevailing thereafter. Light scattered showers will be possible throughout the daytime hours with coverage broadly greater in areas north of I-10. A few thunderstorms cannot be ruled out, though chances and confidence is too low to include with the current TAF. Showers taper off this evening with lower cloud decks filling in again during the early morning hours of Saturday. 03 && .MARINE... Issued at 1205 AM CDT Fri Jul 4 2025 Surface high pressure remains in control over the central Gulf, keeping south to southeasterly winds across the Upper TX coast. Overall, expect light to occasionally moderate winds and low seas in the next 7 days. Isolated showers and storms are expected each day, with the best chances early next week. JM && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 90 76 92 73 / 30 20 10 0 Houston (IAH) 91 78 94 75 / 30 10 10 0 Galveston (GLS) 89 82 90 80 / 20 10 10 0 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ DISCUSSION...JM AVIATION...03 MARINE...JM