Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
Issued by NWS Houston/Galveston, TX
286 FXUS64 KHGX 302337 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 637 PM CDT Sat Aug 30 2025 ...New AVIATION... .KEY MESSAGES... Issued at 1252 PM CDT Sat Aug 30 2025 - WPC has a Slight to Marginal Risk of Excessive Rainfall across Southeast TX through Sunday night. A Marginal Risk continues through Monday night. - Labor Day should generally be cooler with rain chances continuing, particularly over areas near and south of I-10. Rain chances decrease next week as drier air filters into the region. - High temperatures should remain relatively near seasonal averages; a bit cooler where it rains, a bit warmer where it does not. At night, lows should gradually slide through the 70s towards the upper 60s inland as the drier air filters in. && .DISCUSSION... Issued at 1252 PM CDT Sat Aug 30 2025 Expecting a somewhat active weather pattern this weekend as a weak frontal boundary hovers in and near the Piney Woods region today and tonight. The mid level high pressure remains over Western TX and could limit the development of showers and thunderstorms. However, it is weaker today although most of the rain activity is currently firing up around the eastern periphery of the high this morning. It may be the case that the combination of the frontal boundary and PWs of 1.9-2.3" currently over Southeast TX, may be enough to give us a few rounds of showers and thunderstorms later this afternoon and evening. Rain chances will decrease tonight as diurnal heating and instability decreases. Sunday looks to be a better set up for showers and thunderstorms, as the mid level high pressure shifts a little more to the west, the frontal boundary moves closer to the coastal locations, and vort maxes pass overhead while PWs increase to 2.0-2.4" over much of Southeast TX. There is a good chance for showers and thunderstorms to continue well into late Sunday night. We are expecting for the active weather pattern to persist into Monday, and although the higher rain chances should be focused closer to the areas near and south of I-10 due to the proximity of the frontal boundary, we cannot discard at least isolated activity over areas north of this region. Given the amount of moisture we have in place today into Monday, we might see some storms producing heavy rainfall at times with rain rates of 2-3" per hour. Ponding of water along roadways and minor flooding over poor drainage areas are not out of the question. Beware of slow moving storms, as they can lead to quicker accumulations. WPC has placed a Slight Risk (level 2 of 4) for Excessive Rainfall over the Brazos Valley and Piney Woods region for today and tonight, while the rest of Southeast TX remains under a Marginal Risk (level 1 of 4). The Slight Risk extends southward into the northern portions of Harris County on Sunday. A Marginal Risk for much of Southeast TX will continue into Monday night. We are not under the Severe Thunderstorms outlook, however, some strong storms could produce strong gusty winds at times. Make sure to check the radar imagery and traffic conditions before you begin your commute. Strong storms will be capable of producing frequent lightning and gusty winds...make sure to have an alternative option for outdoors activities this holiday weekend. Remember, when thunder roars, head indoors. A dry reinforcing frontal boundary may pass through on Wednesday, but not much rain is expected from this one. Thus, expect a more tranquil weather pattern starting Tuesday and continuing into the end of the work week as drier air moves in from the north in the wake of the two frontal boundaries. With respect to temperatures, we will continue to see high temperatures generally in the upper 80s to lower 90s today. The highs may remain mostly in the 80s on Sunday and Monday. Temperatures will then rise back into the upper 80s to lower 90s by Tuesday and continuing through the end of the week. As for the low temperatures, we will begin to see slightly cooler nighttime temperatures Tuesday night into the end of the week. Expect lows to dip into the mid to upper 60s over areas north of I-10, the lower 70s over areas near and south of I-10, and the upper 70s along the coasts. Cotto && .AVIATION... (00Z TAF Issuance) Issued at 631 PM CDT Sat Aug 30 2025 SHRA/TSRA activity is expected to diminish this evening, with areas of MVFR and potentially IFR developing overnight. SHRA may develop again late tonight (after 09Z), mostly in our southern and coastal zones. By mid morning Sunday, the chance of shra/tsra increases from north to south. For now, chance of seeing at least rain is high enough to warrant VCSH mention in most of the TAFs, while TSRA is limited to a PROB30. That being said, we may have to upgrade the TSRAs to TEMPO groups when confidence increases regarding TSRA coverage and timing. Winds will generally be light and variable. But higher winds are likely in the vicinity of TSRA. && .MARINE... Issued at 1252 PM CDT Sat Aug 30 2025 Generally light and variable winds with seas of 2 feet or less are expected through early next week. Isolated to scattered showers and thunderstorms are expected today as a weak frontal boundary moves into Southeast TX today and meanders near the Piney Woods region tonight. The frontal boundary is expected to sag southward and into the coastal waters later on Sunday into Monday and will lead to scattered to widespread showers and thunderstorms through Monday night. Strong winds, frequent lightning, and elevated seas may occur in and near stronger storms. Drier conditions are expected mid-week into the end of the work week as a drier airmass moves into Southeast TX in the wake of the front. Isolated showers and thunderstorms may still develop at times, however. Cotto && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 75 85 72 86 / 50 80 50 60 Houston (IAH) 78 86 74 86 / 40 80 50 70 Galveston (GLS) 80 89 78 88 / 50 60 60 70 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ DISCUSSION...Cotto AVIATION...Self MARINE...Cotto