


Area Forecast Discussion
Issued by NWS Austin/San Antonio, TX
Issued by NWS Austin/San Antonio, TX
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
685 FXUS64 KEWX 162300 AFDEWX Area Forecast Discussion National Weather Service Austin/San Antonio TX 600 PM CDT Fri May 16 2025 ...New AVIATION... .UPDATE... Issued at 507 PM CDT Fri May 16 2025 A Severe Thunderstorm Watch has been issued across Burnet, Llano, Williamson counties until midnight tonight. Isolated thunderstorms has developed and remain possible across these areas. Large to very large hail is the main hazard followed by strong damaging winds. The heat advisory remains in effect until 7 pm CDT as well for regions generally along and east of the I-35 corridor where heat indices currently are running in the 104 to 111 degree range. && .SHORT TERM... (Tonight through Saturday night) Issued at 236 PM CDT Fri May 16 2025 Key Messages: - Heat Advisory remains in effect through early evening for portions of South Central Texas. - The heat continues on Saturday with elevated heat index values over portions of South Central Texas. - Low chances for isolated strong to severe thunderstorms this afternoon/early evening and Saturday afternoon/evening. The hot weather conditions continue across South Central Texas with highs in the upper 80s across the Hill Country and lower to mid 90s elsewhere as of 2 PM CDT. Heat indexes are ranging from mid to upper 90s with a few locations at 100-103 across the Hill Country and from 100 to 107 range over the coastal plains and the southern part of the Rio Grande. Expect these values to increase as we hit the heating peak time frame sometime between 4 and 6 PM CDT. With that said, heat index values are likely to reach the 106 to 111 range over areas included in the Heat Advisory. Other than the heat, we have a slight chance for an isolated or two strong to severe storms to develop across the Llano, Burnet, and Williamson Counties late this afternoon ahead of the dryline (warm and moist sector). If they do develop, they could produce large hail and damaging wind gusts. As the evening progresses, increased moisture in the form of clouds spreads across the local area with overnight lows in the lower to upper 70s. Patchy fog is expected to develop across the coastal plains as early as midnight and then pushes to the northwest toward the I-35 corridor. Saturday starts warm with mostly cloudy to cloudy skies, however, by noon time, partly cloudy skies should dominate most locations of South Central Texas. By noon time, temperatures should be in the mid to upper 80s to lower 90s. Another hot day is in store with maximum highs expected to reach the mid to upper 90s across most areas and from 100 to 105 along the Rio Grande. With dewpoint temperatures in the mid to upper 60s to lower 70s along and east of the I-35 corridor and the southern part of the Rio Grande, can`t rule out heat index values ranging from 106 to 108 across the coastal plains and up to 111 across portions of the southern portion of the Rio Grande. We are holding off on issuing a Heat Advisory for Saturday at this time. Future weather forecast packages may include a Heat Advisory using latest model guidance. Just continue to exercise heat safety measures. Saturday could look different across the Rio Grande, southern Edwards Plateau, and the Hill Country as strong to severe thunderstorms develop ahead of the dryline and couple of upper level pulses of energy arriving in the afternoon and early evening. These storms could produce large hail and damaging wind gusts. The activity likely lingers through the middle evening period. Between the rain and cool pool of these storms, overnight lows across the southern Edwards Plateau and Hill Country are forecasted to drop to the upper 60s with the rest of the local area in the 70s. && .LONG TERM... (Sunday through Friday) Issued at 236 PM CDT Fri May 16 2025 Key Messages: - Well above normal temperatures continue Sunday through Tuesday with risk of heat-related impacts - Low chances (10-20%) for showers and storms late Monday afternoon and evening and on Tuesday - Temperatures closer to normal Wednesday and Thursday Dry conditions are forecast Sunday and Sunday night for most areas, with the exception of a low (10-20%) chance of isolated late afternoon and evening storms along the dry line across the northwest Hill Country and southern Edwards Plateau. The dry line advances farther east on Monday afternoon, tapping into better moisture, producing low chances (10-20%) of isolated showers and thunderstorms across the Hill Country and northern I-35 corridor. The dry line retreats back west late Monday night, then a shortwave moving through the southern Plains sends the dry line back east into the Hill Country and I-35 corridor Tuesday, with a cold front overtaking it Tuesday night. Low confidence in timing and chances of convection with these features, and we are currently sticking close to the NBM 20% chances of showers and storms along and east of I-35/I-37 Tuesday. Above average temperatures continue Sunday and through Tuesday, with elevated heat indices east of the dry line. There is lower confidence in the strength of the front and temperatures behind it Wednesday and Thursday, but we have trended high temperatures cooler than the NBM. This puts high temperatures close to, or slightly above, normals for this time of year. && .AVIATION... (00Z TAFS) Issued at 551 PM CDT Fri May 16 2025 This evening`s convection over the Hill Country stretching from near Mason to the Killeen area should remain to the north of our area terminal sites. As a result, expect for continued VFR flight conditions through the first half of the night before low clouds with MVFR then IFR ceilings develop at the I-35 terminals (KAUS, KSAT, and KSSF) after midnight into Saturday morning. A slight reduction in visibility is possible at KAUS as well. KDRT should remain VFR through the night but a few low clouds could arrive at or just after sunrise Saturday. Ceilings should improve to VFR levels into Friday afternoon. Isolated to widely scattered storm will again try to develop late Saturday afternoon and evening. However, confidence at this time remains too low to insert into this TAF package. Winds will remain of light to moderate breezes out of the south-southeast over the I-35 terminals and east-southeast to variable at KDRT. && .CLIMATE... Issued at 236 PM CDT Fri May 16 2025 RECORD MAX TEMPERATURES TUESDAY THROUGH MONDAY (* TIED RECORD WITH MOST RECENT OCCURRENCE SHOWN) FRI SAT SUN MON 05/16 05/17 05/18 05/19 ---------------------------------------------- AUS 97/2018* 97/2018 97/2022 97/2006 ATT 99/2022* 99/2022 98/2022 98/2022* SAT 97/2022* 100/2022 101/2022 101/1989 DRT 107/2013 105/2013 107/2024 108/2020 && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 76 95 74 98 / 10 20 20 10 Austin Bergstrom Intl Airport 76 96 74 97 / 10 20 10 0 New Braunfels Muni Airport 75 97 74 98 / 10 10 10 0 Burnet Muni Airport 74 94 72 95 / 30 30 30 10 Del Rio Intl Airport 80 100 79 103 / 10 30 20 10 Georgetown Muni Airport 75 95 72 96 / 20 30 30 10 Hondo Muni Airport 74 98 73 99 / 10 10 20 0 San Marcos Muni Airport 75 97 73 98 / 10 10 10 0 La Grange - Fayette Regional 77 93 75 95 / 0 10 0 0 San Antonio Intl Airport 77 98 76 98 / 10 10 10 0 Stinson Muni Airport 77 99 76 100 / 10 10 20 0 && .EWX WATCHES/WARNINGS/ADVISORIES... Heat Advisory until 7 PM CDT this evening for Atascosa-Bastrop- Bexar-Caldwell-Comal-De Witt-Dimmit-Fayette-Frio-Gonzales-Guadalupe- Hays-Karnes-Lavaca-Medina-Travis-Uvalde-Wilson-Zavala. && $$ Short-Term...Brady Long-Term...76 Aviation...Brady