Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
Issued by NWS Houston/Galveston, TX
035 FXUS64 KHGX 042335 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 635 PM CDT Fri Jul 4 2025 ...New AVIATION... .KEY MESSAGES... Issued at 1205 AM CDT Fri Jul 4 2025 - Hit-or-miss showers and thunderstorms this afternoon. Overall, chances showers/storms should diminish by early evening... just in time for fireworks. But couldn`t rule out a few isolated lingering late evenings showers. - A daily risk of showers and storms can be expected next week. Best chance of rain on Monday and Tuesday. - Hotter conditions expected by mid-week, with highs mainly in the mid to upper 90s. && .DISCUSSION... Issued at 1117 AM CDT Fri Jul 4 2025 The main feature of interest today is a robust, slow-moving, mid- level disturbance over Central Texas that has brought heavy thunderstorms and flooding to the west of our region today. Our region so far has managed to get away with just widely scattered showers. However, more numerous showers/thunderstorms are possible this afternoon thanks to two lifting mechanisms. The first mechanism being the aforementioned disturbance. Nearly all of the available guidance is showing some of the system`s vorticity being thrown our way, inducing lift over our moisture rich SE Texas atmosphere. In addition, surface obs suggest some surface convergence over our region. As we continue to add day time heating to the mix, the chance of showers/thunderstorms increases, especially from the I-10 corridor points north. Showers/storms should diminish as we lose daytime heating this evening. The disturbance is expected to drift southward and away from our region tomorrow. PoPs are generally lower as a result. But the system may still be close enough to provide lift, particularly over our western counties. For now, we have 20-30 PoPs, mostly west of I-45 and south of I-10. We`re expecting less system driven lift on Sunday. However, daytime heating and mesoscale boundaries (sea breeze, bay breeze boundary and whatnot) may still be enough to spark some isolated activity. A mid/upper trough is developing over the eastern Gulf today. This trough is expected to drift slowly westward, effecting our atmosphere by Monday and Tuesday. The added lift is expected to enhance diurnal and mesoscale boundary related convective development on Monday and Tuesday. So there is a better chance of showers/thunderstorms on Monday/Tuesday, especially across our eastern and southern counties. Temperature wise, afternoon highs today are expected to average in the upper 80s to low 90s. For Saturday-Tuesday, highs are expected to mostly be in the low to mid 90s. Beyond Tuesday, the pattern appears more "ridgy" with higher temperatures and lower (though not zero) PoPs. In fact, our current temperature grids are showing many areas in the upper 90s by the second half of the week. However, global models once thought that we would be under robust ridging with low PoPs and upper 90s temps by today. Obviously, that`s not how things turned out. So keep that in mind when looking at the hotter and drier forecast for later next week. The primary reason why I went along with the hotter/drier guidance is due to the prospective pattern`s consistency with local climatology. We often find ourselves in the hot doldrums of strong sub-tropical high pressure during the second half of July. So when in doubt, go with climo! && .AVIATION... (00Z TAF Issuance) Issued at 633 PM CDT Fri Jul 4 2025 Light SHRA continuing this evening, and potentially through around midnight. Otherwise, expect generally VFR conditions to prevail with light and variable winds overnight, becoming southerly Saturday. Isolated showers and thunderstorms will be possible again Saturday; however, the potential is too low to warrant mentioning in the TAFs. && .MARINE... Issued at 1117 AM CDT Fri Jul 4 2025 A continued typical summer pattern is expected through much of the next week, feature light to moderate onshore flow, generally low seas, and a daily risk of isolated to widely scattered showers and thunderstorms. The best chance of showers/storms appears to be on Monday and Tuesday, thanks to a mid/upper level system that will approach from the east. && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 75 90 72 92 / 20 20 0 10 Houston (IAH) 77 93 75 94 / 20 20 0 20 Galveston (GLS) 82 90 81 90 / 10 20 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ DISCUSSION...Self AVIATION...Adams MARINE...Self