Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
Issued by NWS Houston/Galveston, TX
208 FXUS64 KHGX 140026 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 726 PM CDT Wed Aug 13 2025 ...New AVIATION... .KEY MESSAGES... Issued at 122 PM CDT Wed Aug 13 2025 - Typical summer-like weather is expected this week with isolated to scattered showers and storms, with the best chances in the afternoon. - The best rain and storm chances arrive Friday and Saturday as more tropical moisture filters in. - High temperatures mainly in the low to mid 90s throughout the week with an increasing temperature trend possible over the weekend into early next week. && .DISCUSSION... Issued at 122 PM CDT Wed Aug 13 2025 Radar shows scattered showers and a few lightning strikes along the Islands, with some activity beginning to develop farther inland. This activity is occurring ahead of a surface trough that is slowly moving across northeastern Texas. In the next several hours, showers and storms will increase in coverage. The combination of peak daytime heating, high PWs (1.9 - 2.1 inches), and the influence of subtle shortwaves aloft will support more scattered showers and storms this afternoon into the early evening. Any storms that develop will likely be slow-moving, increasing the potential for locally heavy rainfall, which could lead to isolated flooding. Gusty winds around 25 to 40 mph will also be possible with any strong storms. These storms are expected to dissipate early this evening (near sunset) with the loss of daytime heating and upper-level forcing. A rinse-and-repeat forecast is anticipated for Thursday. Showers with a few storms are expected over the coast, slowly developing farther inland in the afternoon. The best rain and storm chances arrive by Friday as a plume of tropical moisture filters in. This is associated to a broad area of a low pressure system located over the Yucatan Peninsula. While this system is expected to remain well further south of our region, increased moisture along with passing mid-level vorticity maxes will be enough to support showers and storms through the day. The best precipitation chances will likely be across our southwestern Counties, including the coast. Showers and storms are progged to continue on Saturday; though it will strongly depend on any lingering moisture and upper-level forcing. Will continue with 30 to 50% chance of precipitation. Beyond Sunday, precipitation chances decrease a bit but temperatures begin to increase. A ridge of high pressure briefly strengthens to our east, bringing more subsidence/drier air into early next week. It won`t be completely dry as some troughiness persists in the flow aloft. Therefore, isolated to scattered activity cannot be rule each day. Highs in the mid to upper 90s can be expected early next week, with heat index values up to 107F. Don`t forget to practice heat safety! JM && .AVIATION... (00Z TAF Issuance) Issued at 657 PM CDT Wed Aug 13 2025 Some isolated storms are still developing along some outflow boundaries and are expected to dissipate within the next hour or so. Thereafter, tranquil conditions will prevail along with light VRB winds. Skies are expected to be mostly clear to partly cloudy, although some locations may see BKN decks near sunrise time-frame Thu morning. A rinse and repeat on the local weather pattern is expected on Thu. Look for showers and storms developing over the coastal locations and inland areas south of I-10 during the morning hours, followed by showers and storms developing further north during the afternoon to early evening hours. One small difference for Thu is that we may have slightly more moisture and storm coverage, in particular in the afternoon. Stronger storms will be capable of producing strong gusty winds, frequent lightning, and periods of heavy downpours which could lower vis/cigs. In addition, flying conditions may be a little bumpy at times. Showers and storms are expected to dissipate in the evening. Cotto && .MARINE... Issued at 122 PM CDT Wed Aug 13 2025 Slow-moving showers with isolated thunderstorms will continue to develop along the coast, before gradually moving further inland later this afternoon. A daily risk of showers and storms will continue over the next several days, with the best chances Friday and Saturday as more tropical moisture moves in. Overall, light winds (offshore early in the morning, becoming onshore in the afternoon/evening) and low seas can be expected in the next 7 days. The National Hurricane Center continues to monitor a tropical wave over the Yucatan Peninsula. There is a 10 percent chance of cyclone formation across the southwestern Gulf beginning on Thursday. Regardless of development, minimal impacts are expected across the Upper TX coast, other than an increased risk of rip currents. JM && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 76 97 77 98 / 20 30 10 20 Houston (IAH) 79 96 79 95 / 30 50 10 50 Galveston (GLS) 83 91 84 90 / 20 40 10 40 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ DISCUSSION...JM AVIATION...Cotto MARINE...JM