textproduct: Austin/San Antonio

KEY MESSAGES

- A tale of two seasons continues...

- A strong cold front arrives late Sunday bringing chances of rain (20-40%) and a significant drop in temperatures.

- A near widespread freeze is possible Wednesday morning

SHORT TERM

(Tonight through Friday night) Issued at 1140 AM CST Thu Dec 25 2025

For this Christmas day high pressure continues to dominate over the area with many areas seeing very warm temperatures in the upper 70s to low 80s however the records for today are much higher so not expecting any records to be broken. We don't cool down much at all tonight as warm south-southwesterly winds continue to keep moisture across the area. Because of this we could see the redevelopment of fog really anywhere across the area, as dew points remain exceptionally moist for this time of year and winds stay rather light. Models remain all over the place on where we could see fog hopefully we will get a better idea as nightfall comes.

Speaking of, lows should remain in the low 60s while this is anomalously warm for this time of year I don't think we quite reach record warm low criteria for Austin however, San Antonio is definitely within reach to be broken tonight (see Climate Section below). Highs Friday will be a touch warmer as the ridge remains overhead though starts to flatten a bit with high pressure just off to our east. Rather than having a moderating impact on our temperatures, the low level winds will become more southwest thus the air coming in off the mountains of Mexico should help to keep temperatures very warm into the region. Expect highs to be in the low 80s to even some mid 80s not out of the question especially across parts of Llano and Burnet counties and parts of the Coastal Plains. Records after Christmas day are much easier to break as we will remain some 20 degrees above climatological levels for this time of year. Rinse and repeat for lows Thursday night should remain very warm with many staying in the mid 60s which could challenge record warm lows for Del Rio but Austin and San Antonio seem a bit out of reach with unless we stay above 70 degrees.

LONG TERM

(Saturday through next Thursday) Issued at 1140 AM CST Thu Dec 25 2025

For the long term expect a tale of two seasons with summerlike temperatures to continue into Saturday before winter makes its reappearance by Sunday evening. Expect temps to run some 15-20 degrees above normal for this time of year with yet another day of near record to record high temperatures expected Saturday, as the ridge remains overhead and we continue to be influenced by low level southerly flow. Right now we are explicitly forecasting record highs for all except Del Rio(see Climate Section below)

Expect this ridge to start to gradually weaken with time as we move into Sunday as a strong cold front moves across Texas and eventually our area by early Sunday evening. This is when we expect quite a significant change in the weather pattern that has remained stagnant for the last week or so. With this frontal passage it seems we could squeeze out of few showers and isolated thunderstorms due to the sharp contrast in temps and airmasses. The highest chances remain over the I-35 Corridor where the best forcing resides.

Additionally, as this front moves through expect a very sharp drop in temps and dewpoints as strong northerly winds really ramp up, in fact we may end up needing a wind advisory as we could see winds sustained above 26 mph with gusts even higher into the first half of Monday. These winds and subsequent strong CAA will allow areas that had dewpoints close to 70 degrees Sunday afternoon to drop to barely 20 to 30 degrees by early Monday morning, thats a drop of nearly 40-50 degrees in about a 12 hour span! These strong northerly winds will help to enhance the strong cold air advection helping low temps to really drop. Many will see a 30-40 degree difference in temperatures with many waking up to lows in the upper 30s low 40s by Monday morning. Expect strong CAA to continue into Monday with temps going from well above normal to well below normal with folks only managing to reach the upper 40s to low 50s as these strong northerly winds continue to pump in colder Canadian air. We could also see elevated fire weather concerns for Monday as dewpoints and RH values continue to fall we could eventually see many areas with dewpoints bottoming out in the single digits, this will be something we continue to monitor and watch. CAA continues into Tuesday with highs remaining in the 50s.

Additionally,both Monday and Tuesday evenings freezes look likely with a widespread freeze looking likely for all areas by Wednesday morning. By Wednesday we warm up as we finally see the return of southerly flow with many seeing highs back to seasonal normals, meaning low 60s for all. The slight warmup continues into Thursday with many seeing highs back into the mid to upper 60s to around 70. So enjoy the warmth for the next few days because we finally start to feel more like winter by the latter half of this weekend and especially early next week.

AVIATION

(18Z TAFS) Issued at 1140 AM CST Thu Dec 25 2025

IFR/LIFR cigs are forecast to affect KDRT for the next couple of hours. MVFR cigs across the San Antonio airports are forecast to linger around for the next hour or two before becoming VFR. Otherwise, VFR conditions are forecast for all area sites by or shortly after 20Z. A southerly flow around 5 to 10 knots is forecast to prevail through the forecast period. Cigs and vsbys return to MVFR, IFR, and even LIFR overnight through late Friday morning. The 12Z HREF model probabilities for ceilings less than 1 kft range from 50 to 90 percent overnight with the highest probabilities favoring the San Antonio area. As far as reduced visibility/fog developing overnight, the HREF probabilities range from the mid 20s to mid 50s for vsbys less than 1 mile. There is definitely an opportunity for lower cigs and vsbys to bring VLIFR conditions, however, confidence is higher for the MVFR to LIFR category range. VFR conditions return across all terminals in the afternoon period.

CLIMATE

Issued at 1020 PM CST Wed Dec 24 2025

Record High Temperatures

12-25 12-26 12-27 Austin Bergstrom 91 (1955) 85 (2016) 82 (2024) Austin Camp Mabry 90 (1955) 84 (2016) 79 (2021/1954) San Antonio 90 (1955) 83 (2016/2008) 82 (2005) Del Rio 87 (1955) 80 (2024) 84 (2005)

Record Warm Low Temperatures 12-25 12-26 12-27 Austin Bergstrom 68 (2016) 73 (2015) 68 (1971) Austin Camp Mabry 68 (2016) 70 (2016) 67 (2021) San Antonio 67 (2016) 71 (2015) 68 (1971) Del Rio 63 (2015) 60 (2021) 65 (2019)

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 64 82 66 82 / 0 0 0 0 Austin Bergstrom Intl Airport 64 82 65 82 / 0 0 0 0 New Braunfels Muni Airport 64 80 64 82 / 0 0 0 0 Burnet Muni Airport 61 82 63 80 / 0 0 0 0 Del Rio Intl Airport 60 81 61 82 / 0 0 0 0 Georgetown Muni Airport 63 83 64 82 / 0 0 0 0 Hondo Muni Airport 61 81 61 82 / 0 0 0 0 San Marcos Muni Airport 63 82 64 83 / 0 0 0 0 La Grange - Fayette Regional 65 82 66 83 / 0 0 0 0 San Antonio Intl Airport 65 80 66 82 / 0 0 0 0 Stinson Muni Airport 66 82 66 83 / 0 0 0 0

EWX WATCHES/WARNINGS/ADVISORIES

None.