


Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
Issued by NWS Houston/Galveston, TX
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285 FXUS64 KHGX 160541 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 1241 AM CDT Wed Jul 16 2025 ...New DISCUSSION, MARINE, TROPICAL... .KEY MESSAGES... Issued at 1202 AM CDT Wed Jul 16 2025 - Dry, but hot today as weak high pressure builds over the region. - Increasing tropical moisture will lead to increased coverage of showers and thunderstorms late Thursday through Friday with locally heavy rainfall possible. - NHC continues to monitor a disturbance that will be entering the northern Gulf on Wednesday, giving it a 40% chance of development into a tropical system in the next couple of days. Regardless of development, increased rain chances are likely late Thursday through Friday. && .DISCUSSION... Issued at 1202 AM CDT Wed Jul 16 2025 A slight increase in mid-level ridging and drier air moving into the region will result in the low rain chances on Wednesday through early Thursday - practically the lowest rain chances we`ve had in over a week. There still might be an isolated, short-lived shower that develops thanks to daytime heating on Wednesday afternoon, but overall we will be rain free through early Thursday. However, the increasing heights aloft and reduced moisture will lead to afternoon temperatures climbing into the upper 90s in spots along the I-10 corridor. Rain chances do begin to increase from the east late Thursday with chances increasing as we head into Friday. This increase in moisture will be associated with the disturbance currently located in northern Florida that the NHC is monitoring for development into a tropical system as it tracks through the northern Gulf over the next few days. NHC gives it a 40% chance of development into a tropical depression or named storm within the next 2 days - more on that in the tropical section below. Regardless of development, this disturbance will be bringing a surge in PWATs (up to 2-2.4"), so we can expect increased rain chances with locally heavy rainfall possible Friday through early Saturday. WPC has placed the I-45 corridor in a Marginal Risk (level 1 of 4) for Excessive Rainfall on Friday with eastern Polk, eastern Liberty, and most of Chambers county in a Slight Risk (level 2 of 4). WPC continues the risk of Excessive Rainfall into Saturday, but shifts the threats further east with areas east of I-45 in a Marginal Risk (level 1 of 4) and the Slight Risk out of our region and more towards the TX/LA border. Looking past this potential tropical system, expect warming conditions Sunday into the start of the work week with temperatures rising back into the mid 90s (and possibly into the upper 90s). With some drier air in place, rain chances will remain on the lower-side with PoPs maxing out near 15-20% during the afternoon hours thanks to daytime heating. Fowler && .AVIATION... (00Z TAF Issuance) Issued at 505 PM CDT Tue Jul 15 2025 Isolated afternoon showers/storms will taper off this evening as light and variable winds settle in across the region. Patchy fog and CIGS may develop over portions of the region during the early morning hours of Wednesday. MVFR conditions may develop with IFR FLs possible in some spots, mostly north of Houston. Conditions improve after daybreak with VFR largely dominating across the area. Southwest winds strengthen during the daytime, shifting south/southeast during the afternoon, then becoming light again in the evening. 03 && .MARINE... Issued at 1202 AM CDT Wed Jul 16 2025 Light onshore winds around 5-10kt (and gusts to 15kt) and seas of 2 to 3 feet will persist through the next few days. Drier air has moved in, so expect much lower coverage of showers and thunderstorms through early Thursday. From late Thursday into Friday, rain chances are expected to increase as a tropical disturbance approaches SE TX from the northern Gulf region. There still remains uncertainty regarding the development and track of this disturbance and more information will be known once the system moves into the Gulf waters on Wednesday. NHC maintains a 40% chance of formation through the next 48 hours as the system moves through the northern Gulf. Regardless of development, we can expect the increased rain chances late Thursday through Friday or early Saturday. Current wave modeling does not factor in any tropical development, so its possible that wave height forecast may increase for Friday *IF* the system does strengthen. Please continue to monitor the upcoming forecasts. Fowler && .TROPICAL... Issued at 1202 AM CDT Wed Jul 16 2025 Not much change in this discussion that hasn`t been talked about in the previous discussions. NHC is monitoring a disturbance, currently located in northern Florida, for strengthening into a tropical system giving it a 40% chance of development within the next 2 days. Conditions are favorable for development, but there remains uncertainty in the forecast track of this system. This system will move westwards through the northern Gulf, but how far west it gets before turning northwards is uncertain (for now, most guidance has it turning northwards into Louisiana before reaching our region, if it develops at all, but this guidance may change once/if a center of circulation develops), and how far offshore the center of circulation develops (a track closer to the coast means less time over water and potentially drier air impacting development). Again, regardless of development into a tropical system, an increase of moisture will lead to increased chances of showers and thunderstorms in SE Texas late Thursday through Friday. Fowler && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 94 72 94 74 / 0 0 20 0 Houston (IAH) 95 75 93 76 / 10 0 20 20 Galveston (GLS) 90 80 90 80 / 0 0 20 40 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ DISCUSSION...Fowler AVIATION...03 MARINE...Fowler