textproduct: Austin/San Antonio

KEY MESSAGES

- Patchy fog mainly over the Coastal Plains around sunrise this morning.

- Mostly well above normal temperatures for the weekend through next week.

- Dry weather for the next seven days.

SHORT TERM

(Today through Sunday) Issued at 1207 AM CST Sat Dec 20 2025

Gulf air with higher moisture is spreading across the region and should bring along with it some low stratus closer to daybreak across most of South-Central Texas and patchy fog over mainly the Coastal Plains. Some cloud cover could stick around along the Balcones Escarpment and I-35 corridor into the late-morning, but sunny skies should develop this afternoon. Breezy low-level flow should make for an unseasonably warm Saturday afternoon with highs in the upper 70s to low 80s for most. Some of the cloudier spots may hold out in the 60s for longer, but expect quick warming to accompany any clearing of the clouds as temperatures aloft approach the climatological maximum for this time of year and mix down to the surface.

A weak cold front then pushes across the area early from the northwest Sunday morning. The source region for its airmass doesn't look especially cold and the front lacks supportive winds aloft, so I don't expect a lasting changeup in the weather aside from just Sunday into Monday morning with the possibility of briefly cooler temperatures and a temporary switch to light northerly winds behind the front. Lows Sunday morning will vary depending on the frontal position, with morning temperatures in the 40s behind the front (more likely over the Hill Country and Southern Edwards Plateau) and temperatures in the 60s accompanied by fog and cloudiness ahead of the front (more likely over the Coastal Plains). The temperature forecast Sunday afternoon is somewhat tricky and hinges on whether or not clouds are able to clear behind the front. The WRF-ARW and NAM guidance suggests that a cloud deck could maintain cooler temperatures Sunday afternoon (in the 50s and 60s) while the HRRR/RAP, RRFS, and WRF-FV3 suggest sufficient clearing for temperatures to still make it into the 70s and 80s, especially over the Rio Grande Plains. The difference appears to arise in part due to the handling of a weak meso-low along the front, with a more distant low favoring less clouds and a closer approach favoring the cooler cloudier scenario. Regardless, significant weather is not anticipated with the front, and any changes it does bring will be quickly replaced by a resurgent stream of Gulf moisture heading into the workweek.

LONG TERM

(Sunday night through Friday) Issued at 1207 AM CST Sat Dec 20 2025

The theme for next week is unseasonable warmth. An expansive upper- level ridge is forecast to build across the southern half of the continental US early in the week and then dominate the weather pattern throughout the week. Both NAEFS and EFS ensemble suites indicate this ridge may be the among the strongest on record for late December over our area.

Persistently dry southwesterly flow aloft will help promote unseasonably warm daytime temperatures while a more humid southerly flow off the Gulf and closer to the surface will support unseasonably mild overnight temperatures. Outright daily record warmth for highs and lows are not explicitly depicted in the latest forecast, but we'll likely be in the upper echelons of observed values if not near record territory as temperatures persistently stay 10 to 20 degrees above average across the region. Each day Monday through Friday, highs are forecast to be in the upper 70s to low 80s with lows in the upper 50s to low 60s. Climatologically speaking, these conditions resemble the norms for April. The spread in temperature projections from the the middle 50 percent of models during the week is only about 3 to 5 degrees, so there is good model agreement in the magnitude of the warmth. Rain chances remain minimal throughout the week, though there could be a brief window Monday (less than a 10 percent chance) for some light rain showers accompanying a surge of Gulf moisture.

AVIATION

(12Z TAFS) Issued at 527 AM CST Sat Dec 20 2025

Little to no change to the previous forecast. Only minor change was slightly earlier arrival time of MVFR ceilings at SSF and AUS. Otherwise, expect MVFR to IFR and perhaps even a brief period of LIFR at SAT/SSF/DRT before lifting to VFR quickly later this morning.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 77 53 71 54 / 0 0 0 0 Austin Bergstrom Intl Airport 75 51 72 52 / 0 0 0 0 New Braunfels Muni Airport 75 52 74 53 / 0 0 0 0 Burnet Muni Airport 79 47 67 49 / 0 0 0 0 Del Rio Intl Airport 79 49 77 51 / 0 0 0 0 Georgetown Muni Airport 79 48 69 51 / 0 0 0 0 Hondo Muni Airport 75 48 79 52 / 0 0 0 0 San Marcos Muni Airport 76 51 74 52 / 0 0 0 0 La Grange - Fayette Regional 77 59 74 56 / 0 0 0 0 San Antonio Intl Airport 74 53 76 55 / 0 0 0 0 Stinson Muni Airport 77 55 76 56 / 0 0 0 0

EWX WATCHES/WARNINGS/ADVISORIES

None.