


Area Forecast Discussion
Issued by NWS Austin/San Antonio, TX
Issued by NWS Austin/San Antonio, TX
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297 FXUS64 KEWX 201750 AFDEWX Area Forecast Discussion National Weather Service Austin/San Antonio TX 1250 PM CDT Tue May 20 2025 ...New AVIATION... .UPDATE... Issued at 811 AM CDT Tue May 20 2025 A quick update to the forecast has been made to increase rain chances across portions of the Rio Grande plains into the coastal plains as radar shows new storms going up over the mentioned region as a cold front moves in from the north. A few strong storms are possible with gusty winds, small hail and lightning strikes being the main weather concerns. && .SHORT TERM... (Today through Wednesday) Issued at 142 AM CDT Tue May 20 2025 Key Message: - Low chances for strong to severe thunderstorms early this morning as a front moves across South Central Texas. A dryline in our far western counties is seen early this morning with a cold front located over northern Texas. The dryline will slowly move east as the cold front progresses southeast towards our area during the early morning hours. Around sunrise, these features catch up to one another with the front located somewhere over the southern Edwards Plateau and Hill Country. Models have continued to indicate isolated thunderstorm development ahead of these features a few hours before sunrise with varying solutions on the strength of any storms. The most favored locations for storm development looks to be over the Hill Country with storms progressing towards the southern I-35 corridor and into the coastal plains through mid- morning before weakening and dissipating. Instability remains high overnight so storms may become strong to severe with their initial development with hail and damaging wind gusts the main hazards. Mostly clear skies and northerly wind will prevail today as surface high pressure moves into western Texas this afternoon. Highs today will be slightly cooler in the north but still reach into the low 90s. Further south, triple digit temperatures are again forecast for the Rio Grande Plains with afternoon temperatures in the mid to upper 90s across much of the I-35 corridor and coastal plains. Most locations except those in the far south will see slightly cooler temperatures tonight. Unfortunately, a big cool down is not expected for Wednesday behind the front, though highs should largely remain in the 90s with only triple digit temperatures forecast for the Rio Grande Plains. && .LONG TERM... (Wednesday night through Monday) Issued at 142 AM CDT Tue May 20 2025 An upper level disturbance moving between northeast Mexico and South Texas on Wednesday night into Thursday morning could bring isolated showers and thunderstorms across the Rio Grande during the period. Overnight lows are forecasted to range from the upper 60s across the Hill Country to mid 70s elsewhere. A hot day is in store for Thursday with highs in the 90s for the most part and up to 102 across the southern part of the Rio Grande. Heat index values range from 100 to 106. There is a slight chance for showers and thunderstorms across the southern Edwards Plateau, Hill Country, and portions of the I-35 corridor in the afternoon and part of the evening as an upper level disturbance/trough axis pushes across the local area. Dry and a bit cooler on Friday with highs is the low to mid 90s across the Hill Country to near 102 along the southern part of the Rio Grande. Stays dry and hot through the first half of the Memorial Day weekend. By Sunday night into Monday, isolated to scattered showers and thunderstorms are expected across most of the local area as a cold front pushes over. In the wake of the frontal boundary, cooler temperatures are expected to spread across South Central Texas through the middle of the week. && .AVIATION... (18Z TAFS) Issued at 1228 PM CDT Tue May 20 2025 Drying in the lower levels will keep VFR conditions in place through the remainder of the forecast period along the I-35 corridor. Some gusty north winds will continue this afternoon, with gusts easing by early evening. Out west at DRT, we also anticipate gusty north winds until roughly 23Z. Some easterly upslope flow late in the period may bring back some low clouds to DRT and for now, we will mention SCT clouds near 3K AGL beginning 10Z. A few of the models show clouds may be thick enough for MVFR and we will continue to monitor model trends before including MVFR cigs at DRT. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 96 66 96 72 / 0 0 0 0 Austin Bergstrom Intl Airport 96 63 97 71 / 0 0 0 0 New Braunfels Muni Airport 98 66 96 71 / 10 0 0 0 Burnet Muni Airport 91 63 92 69 / 0 0 0 0 Del Rio Intl Airport 99 72 97 76 / 0 0 0 10 Georgetown Muni Airport 92 61 94 70 / 0 0 0 0 Hondo Muni Airport 98 69 97 72 / 10 0 0 10 San Marcos Muni Airport 98 64 97 71 / 10 0 0 0 La Grange - Fayette Regional 96 66 96 72 / 20 0 0 0 San Antonio Intl Airport 98 69 97 74 / 10 0 0 0 Stinson Muni Airport 101 70 97 75 / 10 0 0 0 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ Short-Term...Platt Long-Term...Tran Aviation...Platt