Area Forecast Discussion
Issued by NWS Austin/San Antonio, TX
Issued by NWS Austin/San Antonio, TX
121 FXUS64 KEWX 301852 AFDEWX Area Forecast Discussion National Weather Service Austin/San Antonio TX 152 PM CDT Sat Aug 30 2025 .KEY MESSAGES... - Rain chances today from San Antonio northward, then all areas Sunday into Monday. - Locally heavy rains possible today through Monday. The main threat is urban and small stream flooding with a marginal to slight risk of flash flooding. - Above average temperatures today, then decreasing to below average by Monday, then near average remainder of the week. && .SHORT TERM (THROUGH MONDAY NIGHT)... A cold front is sagging into our area over portions of the southern Edwards Plateau and Hill Country early this afternoon and is expected to remain near the northern fringes of our CWA through tomorrow morning before shifting south across our area Sunday into Monday. PWATs remain high near the frontal boundary and increase to over 2 inches across the area as the front moves south tomorrow. Latest guidance favors scattered showers and storms this afternoon and evening towards the northern reaches of the CWA and Hill Country, though some models do have development as far south as Bexar County. Overnight, development in Central Texas may skim our northern areas early Sunday morning. The best chances for rain come Sunday afternoon through Monday as the front enters our area. Don`t expect a total washout for the holiday weekend as showers and storms will likely remain scattered. The storms that we do see though may be efficient rainmakers with slow storm motions or storms could move over the same locations. This will continue the isolated flooding threat through Monday with mainly just pockets heavy rain totals. Isolated locations may see 3-5 inches though amounts will generally be lesser. WPC has expanded their level 2 of 4 risk today into tomorrow morning for the most northern portion of the CWA, generally from a Fredericksburg to Kyle to Giddings line northward. For Sunday into Monday morning, the level 2 of 4 risk is in place for much of the CWA. Still believe the main threat will be urban and small stream type flooding, but will have to watch for any slow or training storms that could produce flash flooding. The highest potential for any flash flooding looks to be mid-afternoon Sunday through Monday afternoon. Considered a flood watch, but with most widespread activity expected to hold off until tomorrow afternoon and little agreement in coverage with models have opted to not issue at this time but will continue to monitor for this potential. In addition to heavy rain, gusty wind from 40-50 mph will be possible with the strongest storms. Hot temperatures and heat index values peak today but a cooling trend will be seen tomorrow and Monday with increased cloud cover and rain chances. && .LONG TERM (TUESDAY THROUGH SATURDAY)... South Central Texas will be under northwesterly flow aloft Tuesday through late week with mid-level ridging to the west and deep troughing to the east. Tuesday should be mainly dry as the front continues to shift south out of the area with mainly dry conditions through the rest of the week. Will have to watch out for some disturbances in northwest flow or a front late in the period which return some low rain chances to the area. Temperatures look to remain near early September averages. && .AVIATION (19Z SATURDAY THROUGH MONDAY)... VFR conditions with southerly to southeasterly winds under 10kts are forecast for all terminals through the period except KAUS. For KAUS we expect SHRAs/TSRAs to form this afternoon and are already seeing evidence of this on radar and satellite imagery, have added PROB30s from 21Z to 24Z. Very low confidence on how far east and south these storms make it and if KSAT will be impacted. Have kept PROB30s in for the evening period but may need to add mention in TAFs earlier if this activity continues. MVFR cigs return late morning for KAUS and continue through end of the period as chances are significantly higher that KAUS will stay locked in the clouds and storms for Sunday. Likewise KSAT should also see higher chances for TSRAs Sunday so have added PROB30s late in the TAF forecast. Otherwise for KSSF expect continued VFR conditions and will watch closely to see how far SHRAs/TSRAs make it this afternoon and will amend as needed. For KDRT expect VFR conditions with east to southeasterly winds 10kts or less. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 76 91 73 88 / 30 60 70 60 Austin Bergstrom Intl Airport 75 91 73 88 / 30 70 60 60 New Braunfels Muni Airport 75 95 73 89 / 20 60 60 70 Burnet Muni Airport 74 87 70 85 / 40 80 70 60 Del Rio Intl Airport 79 99 76 89 / 0 20 60 80 Georgetown Muni Airport 75 89 72 86 / 40 80 70 60 Hondo Muni Airport 74 98 73 89 / 10 30 60 70 San Marcos Muni Airport 75 94 72 89 / 20 60 60 70 La Grange - Fayette Regional 75 90 73 86 / 30 70 60 70 San Antonio Intl Airport 77 97 75 89 / 20 50 60 70 Stinson Muni Airport 78 98 76 90 / 10 40 60 70 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...27 LONG TERM...27 AVIATION...Magnussen