Area Forecast Discussion
Issued by NWS Austin/San Antonio, TX
Issued by NWS Austin/San Antonio, TX
449 FXUS64 KEWX 292332 AAA AFDEWX Area Forecast Discussion...UPDATED National Weather Service Austin/San Antonio TX 632 PM CDT Fri Aug 29 2025 .KEY MESSAGES... - Above average heat and humid today and Saturday, then near to below average temperatures Sunday into next week. - Rain chances in the Hill Country and areas north of San Antonio today spreading south to include the San Antonio area on Saturday, then all areas Sunday into Monday. - Locally heavy rains possible today through Monday. The main threat is urban and small stream flooding with a slight risk of flash flooding. && .SHORT TERM (THROUGH SATURDAY NIGHT)... A cold front is draped across Central Texas today. South of this feature, some showers and isolated thunderstorms are seen which remain just north of the CWA early this afternoon. This activity will move south into the area with hi-res guidance continuing to generate thunderstorms through the evening mainly over the Hill Country and areas north of the San Antonio metro. The front remains in a similar location on Saturday with precipitation chances extended slightly further south into most of the southern Edwards Plateau, Hill Country, coastal plains and I-35 corridor as far south as San Antonio. Above normal PWATs are in place today and tomorrow which will allow for these slow moving storms to produce heavy rainfall and a threat of flooding each day. Spotty rainfall amounts up to 3 inches will be possible each day with stronger storms capable of producing wind gusts up to 50 mph. WPC continues its level 1 of 4 risk for excessive rainfall today and tomorrow, but mostly expect urban and small stream flooding in the short term period. Hot and humid conditions continue are seen today and tomorrow south of the front. Today will be the hottest with slightly more cloud cover expected on Saturday. Highs this afternoon will be in the mid 90s to around 103 degrees, but heat index values will surge from around 100-108 degrees. A few isolated locations may briefly reach heat advisory levels. Heat indices drop a degree or two for tomorrow. Either way, if you`re out this holiday weekend be sure to take heat safety precautions such as drinking water and taking breaks inside or in the shade. Additionally, if thunder roars, go indoors! && .LONG TERM (SUNDAY THROUGH FRIDAY)... A cold front shifts south into the area during the day Sunday bringing the highest rain chances of the week Sunday afternoon through Monday. Forcing by the front and heating will generate showers and thunderstorms over many areas between the two days. Precipitable water values exceed 2 inches for some locations which is above normal for the time of year indicating showers and thunderstorms will be efficient rain makers. Rain totals will vary but with slow moving storms or training storms, isolated totals up to 5 inches are possible which could lead to flash flooding. WPC has now upped the northern half of the CWA in a level 2 of 4 risk for excessive rainfall with a level 1 of 4 risk elsewhere Sunday into Monday morning. In addition to heavy rain, storms could produce gusty winds up to 40 mph. The front hangs out in South Texas on Tuesday leaving some low precipitation chances in the forecast, mainly in our southern and western locations, though most locations will be dry this day. Surface high pressure slides over the area mid to late week with a dry forecast for Wednesday and Thursday. Low rain chances return Friday, though models are pretty varied this far out. Rain chances and clouds bring the coolest temperatures of the week Monday, with temperatures rising to more seasonable values for the rest of next week. && .AVIATION (00Z SATURDAY THROUGH SUNDAY)... Concerns over the next 1-2 hours will be monitoring the potential for isolated convection near the TAF sites. We have kept a PROB30 at AUS through 01Z as some convection lingers roughly 10-15 miles east and southeast of the terminal. For SAT, an outflow boundary should move in around 2345Z bringing a northerly wind shift and perhaps an isolated shower or storm. A PROB30 group through 02Z has been added to the forecast to account for this. We have kept the SSF forecast dry as a decreasing trend is expected through this evening. The next topic of concern will be the possibility of low clouds Saturday morning. We will scale back to a TEMPO group for MVFR at AUS and only mention SCT low clouds in a TEMPO for SAT and SSF. Another round of thunderstorms is possible tomorrow afternoon and will keep the PROB30 for AUS and have also added to the SAT forecast as well. DRT is expected to remain VFR through the period. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 76 96 75 89 / 30 40 40 60 Austin Bergstrom Intl Airport 75 96 75 89 / 30 30 40 50 New Braunfels Muni Airport 74 98 74 93 / 20 30 30 40 Burnet Muni Airport 73 92 73 85 / 30 50 50 80 Del Rio Intl Airport 79 102 79 99 / 0 10 10 30 Georgetown Muni Airport 74 95 74 85 / 30 40 50 80 Hondo Muni Airport 75 99 74 96 / 10 10 10 30 San Marcos Muni Airport 74 98 74 93 / 20 30 30 40 La Grange - Fayette Regional 75 95 75 90 / 30 40 30 70 San Antonio Intl Airport 77 99 78 95 / 20 20 20 40 Stinson Muni Airport 78 101 78 97 / 10 20 20 30 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...05 LONG TERM...05 AVIATION...Platt