


Area Forecast Discussion
Issued by NWS Austin/San Antonio, TX
Issued by NWS Austin/San Antonio, TX
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808 FXUS64 KEWX 151459 AAA AFDEWX Area Forecast Discussion...UPDATED National Weather Service Austin/San Antonio TX 959 AM CDT Thu May 15 2025 ...New UPDATE... .UPDATE... Issued at 947 AM CDT Thu May 15 2025 Updated the rest of the morning period to add a slight chance for showers along the I-35 corridor. These light showers are elevated, however, are reaching the ground. Expect dry weather conditions for the afternoon the high temps in the upper 90s across the Hill Country to 100 to 105 across and east of I-35, Coastal Plains, and Rio Grande. Highest heat index values could reach the 107 to 109 range. && .SHORT TERM... (Today through Friday) Issued at 133 AM CDT Thu May 15 2025 Key Messages: - A Heat Advisory is in effect for parts of South Central Texas this afternoon and evening. - Hot temperatures continue Friday and additional heat products may be needed. Satellite shows scattered high clouds and a few patches of low clouds over the area this morning. Lows will generally be in the 70s, though a few locations in the Hill Country or southern Edwards Plateau could dip into the upper 60s. Later this morning, clouds will clear a bit more with afternoon temperatures rising into the mid 90s to around 105 degrees in the west. A dryline will move into the area with most models stalling this feature just before it reaches the Hill Country. Dewpoints in the 60s are expected ahead of this line leading to some locations seeing heat index values from 100 to 108 degrees. The combination of temperatures and heat indices warrants the continuation of the Heat Advisory for this afternoon, mainly in the south/central portion of the CWA. Moderate south to southeast flow will continue in the low levels today which will allow for low cloud development tonight into Friday morning for most of the area except the far west. This will keep lows slightly warmer than early this morning.. High temperatures and heat index values Friday will be similar to those of today, so additional heat products may be needed. There is a low (15 to 20 percent) chance for thunderstorms in our far northeast late Friday afternoon as the cap tries to erode, otherwise dry conditions are expected. && .LONG TERM... (Friday night through Wednesday) Issued at 133 AM CDT Thu May 15 2025 - Record breaking heatwave continues with additional temperature records likely being broken. - Moderate to Major risk of heat-related impacts through the upcoming weekend and into early next week. The weather pattern for the reminder of this week into the middle of next week remains rather unchanged characterized by a broad, subtropical ridge axis over Mexico into the Gulf with persistent southwesterly flow aloft over south central Texas. Chances for isolated showers and storms across the Hill Country and southern Edwards Plateau are increasing for Saturday as the dryline temporarily surges eastward. Temperatures will remain well above normal through the end of the forecast period with high temperature records likely to be tied or broken. This heatwave will eventually become muggy and possibly even downright oppressive across the area compared to the relatively dry heat we have had the previous couple days. Heat index values of 100-110 are expected across the entire area and throughout the long term. This pushes heat risk categories into the high to even extreme category. If this trend continues we may need to issue additional heat advisories for most. No matter how you slice it, it is going to be a very hot weekend across all of South Central Texas that likely extends into early next week. Please make sure you and your loved ones have a way to stay cool during this early season heatwave. Additional heat safety information and resources can be found at the following websites: www.heat.gov and www.weather.gov/safety/heat As we head into next week, the heat continues though air temps start slowly decreasing but the heat index or feels like remains in the 100-110 degree range. This is in response due to an upper- level trough axis to our west which starts to deepen providing some weak disturbances that move into the region. These disturbances will limit just how high actual air temps can go due to increased moisture and abundant cloud cover. In response rain chances look to increase across the Hill Country into the I-35 corridor with the best chances being Saturday afternoon/evening and again late Monday into Tuesday. It is still too soon to discuss exact timing and amounts but due to these disturbances being over 3 days out we are starting to see models come into better agreement. Toward the end of the forecast period, a couple of the global models show a cold front moving in from the north. Overall confidence is low, but this may bring some temporary relief from the heat. && .AVIATION... (12Z TAFS) Issued at 604 AM CDT Thu May 15 2025 A small area of MVFR to IFR ceilings and visibility are seen along the I-35 corridor through mid-morning, otherwise VFR conditions persist today. A dryline will move into South Central Texas this afternoon with wind from the N/NW over the western half of the area including DRT and S/SE in the east over I-35 terminals. Gusts up to 20 knots may be seen at I-35 sites during the afternoon. Low ceilings will build into the area arriving at I-35 terminals around 07-08Z Friday. && .FIRE WEATHER... Issued at 257 PM CDT Tue May 13 2025 Elevated fire weather conditions continue this afternoon as humidity drops into the single digits and teens behind a dryline moving into the southern Edwards Plateau and Rio Grande Plains. Over these locations, north to northwest wind will mainly be in the 5 to 12 mph range. Very low humidity continues in the far west Friday, but wind should be light over this area Friday afternoon. && .CLIMATE... Issued at 257 PM CDT TUE May 13 2025 RECORD MAX TEMPERATURES TUESDAY THROUGH SATURDAY (* TIED RECORD WITH MOST RECENT OCCURRENCE SHOWN) THU FRI SAT 05/15 05/16 05/17 -------------------------------------------- AUS 96/2003 97/2018* 97/2018 ATT 98/1925 99/2022* 99/2022 SAT 98/2022 97/2022* 100/2022 DRT 102/2022 107/2013 105/2013 RECORD MAX TEMPERATURES FOR MAY ------------------------------- AUS 102 ... set on 05/07/1998 ATT 104 ... set on 05/24/1925 SAT 104 ... set on 05/31/2004 DRT 112 ... set on 05/26/2024 && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 98 75 99 76 / 20 10 10 10 Austin Bergstrom Intl Airport 99 74 99 74 / 20 0 10 10 New Braunfels Muni Airport 100 74 100 74 / 20 0 0 10 Burnet Muni Airport 97 73 98 73 / 10 10 20 10 Del Rio Intl Airport 105 76 105 78 / 0 0 0 10 Georgetown Muni Airport 97 74 98 74 / 20 10 20 10 Hondo Muni Airport 101 73 106 74 / 0 0 0 10 San Marcos Muni Airport 99 73 100 74 / 20 0 10 10 La Grange - Fayette Regional 95 76 96 76 / 0 0 0 0 San Antonio Intl Airport 101 75 102 75 / 20 0 10 10 Stinson Muni Airport 103 76 103 76 / 10 0 0 10 && .EWX WATCHES/WARNINGS/ADVISORIES... Heat Advisory from 1 PM this afternoon to 8 PM CDT this evening for Atascosa-Bexar-Frio-Medina-Uvalde-Wilson. && $$ Short-Term...17 Long-Term...76 Aviation...17