Area Forecast Discussion
Issued by NWS Austin/San Antonio, TX
Issued by NWS Austin/San Antonio, TX
402 FXUS64 KEWX 181518 AFDEWX Area Forecast Discussion National Weather Service Austin/San Antonio TX 918 AM CST Tue Nov 18 2025 ...New UPDATE... .KEY MESSAGES... - Unseasonably warm and muggy through Wednesday with morning low clouds, patchy fog, and drizzle - Locally heavy rainfall with flooding concerns and some strong to isolated severe storms possible late Wednesday night into early Friday with storm system - Higher uncertainty but additional rain chances could occur from the weekend through early next week due to a second Pacific upper level low pressure system && .UPDATE... Issued at 915 AM CST Tue Nov 18 2025 Quick update to remove the mention of fog and drizzle for this morning. Temperatures have warmed and will continue to climb to near record highs this afternoon. && .SHORT TERM... (Today through Wednesday) Issued at 1200 AM CST Tue Nov 18 2025 Very warm and humid conditions persist across the region. Expect morning low clouds to develop into each morning. A stratus deck should continue to be more favored compared to fog across most locations. Patchy fog, if it does occur, is most favored over the Southern Edwards Plateau and western Hill Country. With slightly deeper low-level moisture, some patchy drizzle is possible for Tuesday morning. Wednesday morning may trend even a little better for areas of drizzle along with perhaps some isolated low topped shower activity as the low-level warm and moist air advection intensifies ahead of the approaching weather system. Through the daytime hours on Wednesday, low end shower chances and perhaps a storm is possible but activity looks to remain trapped under a capping inversion aloft at around 700 mb and limited in areal coverage. Afternoon highs will trend from the mid 70s to low 80s over the Hill Country and Southern Edwards Plateau to the mid and upper 80s elsewhere. We will continue to challenge daily record highs in some locations, especially today`s, as they are a little lower in comparison to the surrounding dates. Morning lows will maintain in the 60s to low 70s. && .LONG TERM... (Wednesday night through Monday) Issued at 1200 AM CST Tue Nov 18 2025 The primary window for the more active stretch of weather begins late Wednesday with increasing southwesterly flow and ascent out ahead of the slow moving Pacific storm system. The medium range guidance during the past 48 hours has trended a little slower and not quite as potent with the parent low. However, a preceding impulse ahead of the main low helps fire thunderstorms over our western regions on Wednesday night. There are growing signals with some of the farthest reaching higher resolution short term model guidance showing that these storms could train across the same locations with minimal eastward progression initially. Once the parent low eventually ejects northeast and allows for the frontal boundary and it`s ascent to move into the region, this helps to develop additional rain and storms. This activity should be a bit more progressive and advances this activity east- southeastward across the region from Thursday into/through Thursday night. The prospects for severe weather has decreased a bit thanks to the weaker parent low but there is enough overlap of shear and instability for strong to isolated severe storms. A level 1 of 5 risk for severe weather was introduced for Wednesday night in our western areas and this could be expanded from Thursday through Thursday night farther towards the east with the next day 3 convective outlook issuance. The greatest concern and impacts late Wednesday night through Thursday night would be with excessive rainfall resulting in the potential for some flooding. Right now, the latest ensemble means continue to support rainfall on average up into the 1 to 3 inch range, mainly for the northern 2/3rds of our CWA. Locally higher amounts are likely, especially with some of that newest output mentioned in the previous paragraph from the high resolution guidance. Any of these higher bullseyes would be difficult to pinpoint until near term of the event. There will also be some locations, especially south, that may not get up to an inch. WPC highlights a level 1 to 2 risk of excessive rainfall that could result in flooding from Wednesday night through Thursday night across the region. Conditions are to dry out following the front from west/northwest to east/southeast on Friday but small rain chances may linger across our far southeast counties with the possibility of the front getting hung up along the coast. The forecast uncertainty increases from the weekend through the start of next week as another Pacific upper level low will take shape. Similar to our last few modeled Pacific systems at around this modeled time range, there is quite a bit of inconsistency between run to run regarding the timing and placement of this system. Additionally into and through this weekend, we will also closely monitor the placement of the surface front as it could continue to remain hung up along the coast or portions of South Texas. Pending how the upper pattern evolves, this front could interact and provide some support for rain or clouds through isentropic lift. We`ll continue to keep the forecast near the blended (NBM) guidance that continues to keep low to medium rain chances in the 20 to 50% range. Area temperatures from Thursday onward leave near record warmth behind and should return closer to the seasonal averages with daytime highs, mainly in the 60s and 70s, and overnight lows dropping as low as the 40s and 50s. However, with greater uncertainty, larger than normal temperature adjustments may be needed within the forecast as details become clearer during the progression of time. && .AVIATION... (12Z TAFS) Issued at 505 AM CST Tue Nov 18 2025 MVFR CIGs with patchy IFR CIGs, -DZ, and BR will lift to VFR early this afternoon, then return late this evening into night. S to SE winds 6 to 12 KTs will prevail with a few gusts to 25 KTs midday through evening. && .CLIMATE... Issued at 1200 AM CST Tue Nov 18 2025 Record High Temperatures Tuesday 11/18 AUS 84/2017 ATT 85/1921 & 1986 SAT 88/1986 & 2017 DRT 87/1986 Record Rainfall Thursday 11/20 AUS 1.24"/2009 ATT 1.63"/2009 SAT 1.15"/2009 DRT .20"/1984 && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 85 68 84 69 / 10 0 40 40 Austin Bergstrom Intl Airport 85 67 84 68 / 10 10 40 40 New Braunfels Muni Airport 84 67 84 68 / 10 10 40 40 Burnet Muni Airport 82 66 81 66 / 10 0 40 60 Del Rio Intl Airport 82 69 80 66 / 10 10 60 80 Georgetown Muni Airport 85 67 84 68 / 10 0 40 50 Hondo Muni Airport 84 67 84 66 / 20 10 30 70 San Marcos Muni Airport 85 67 85 68 / 10 10 40 40 La Grange - Fayette Regional 87 67 85 68 / 10 10 30 20 San Antonio Intl Airport 84 69 85 69 / 20 10 40 50 Stinson Muni Airport 85 69 87 70 / 10 10 40 50 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...62 LONG TERM....62 AVIATION...04