


Area Forecast Discussion
Issued by NWS Austin/San Antonio, TX
Issued by NWS Austin/San Antonio, TX
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936 FXUS64 KEWX 221127 AFDEWX Area Forecast Discussion National Weather Service Austin/San Antonio TX 627 AM CDT Tue Apr 22 2025 ...New AVIATION... .SHORT TERM... (Today through Wednesday) Issued at 111 AM CDT Tue Apr 22 2025 Key Messages: - Very humid and warm conditions will rule with returning low to medium (20-60%) rain and thunderstorm chances - There is a level 1 to 2 out of 5 risk for severe thunderstorms late this afternoon through tonight across the southern Edwards Plateau and western Hill Country Rapid dew point recovery is ongoing across the region as a front slides northward as a warm front, and with the southeasterly low- level flow in wake of the boundary. With the returning low-level moisture, low stratus will quickly establish and expand over the region by sunrise. Patchy fog will become possible as well across portions of the coastal plains, southern Edwards Plateau and the western Hill Country. Isolated low topped showers below the cap could also establish this morning as well in those areas. With daytime heating this afternoon, the potential could exist for isolated to widely scattered storms to develop across the area. However, not all short term models show the local development of storms this afternoon with either too much capping or the lack of enough forcing. The primary region where storms are more likely develop will be across West Texas and Mexico from late this afternoon through the evening with the closer proximity of the dryline and the higher terrain influence. While short term models lack any good consistency on movement and placement, storms could attempt to make a run across the Rio Grande sometime around or beyond sunset. Additionally, the activity across West Texas, may also attempt to congeal into a single mesoscale convective system that could slide southeastward towards and into the region from tonight into early Wednesday. The environment with MLCAPE in the 1500 to 2500 J/kg range and deep layer bulk shear around 35 to 40 knots is enough to support severe thunderstorms. The latest SPC convective outlook has added a level 2 of 5 risk across Val Verde County while a level 1 of 5 risk extends eastward into the Hill Country and south along the Rio Grande into Maverick County. The primary hazards are large hail and damaging winds. However, any storms will also be capable of locally heavy rain and frequent lightning as well. The rain/storm chances Wednesday will be highly dependent on the evolution of the storms today through tonight. If a mesoscale convective complex does move through the region, it may zap the available instability and overwork the atmosphere. This would decrease storm chances. Otherwise, if local instability does maintain, then shower and thunderstorms could develop with the daytime heating. At this time, Wednesday`s forecast calls for medium (30 to 60 percent) chances for rain and storms. High temperatures will top out from the mid to upper 80s for the majority to the low to mid 90s along the Rio Grande. Expect the overnight lows tonight to only fall to the mid 60s to near 70 degrees. The highs on Wednesday become dependent on if a storm complex moves across the region or now as well. If so, then the highs will trend lower. For now, the forecast calls for highs into the low to upper 80s area wide. && .LONG TERM... (Wednesday night through Monday) Issued at 111 AM CDT Tue Apr 22 2025 Key Messages: - Chances for showers and thunderstorms continue Wednesday night through Friday. The western part of the country will be under a broad, shallow upper trough at the start of the long term period. Winds will be from the southwest. Southwesterly upper flow will continue through the end of the work week. Beneath this upper pattern the low level flow will be from the southeast during the same time period. This will keep a warm, moist airmass in place over South-Central Texas. Forecast soundings showing this airmass to be conditionally unstable with a good cap above the boundary layer. Models are in good agreement that the dryline over West Texas will stay out there. So any convection will likely be driven by upper level shortwave troughs moving through the pattern or weak outflow boundaries left over from earlier convection. This will lead to a forecast problem best solved in the short term. Thus we are left with broad areas of 30%-60% PoPs each day Thursday and Friday. Given the forecast situation, these PoPs can best be thought of as coverage since there are no foci for convection. There will also be some chance that if storms can form they could be strong to severe. By the weekend an upper level ridge will build over Texas from the south. This will end any chances for rain starting Saturday night and continuing through the end of the period. Temperatures will warm over the weekend reaching the upper 80s to lower 90s by Sunday and adding a couple of degrees Monday. && .AVIATION... (12Z TAFS) Issued at 615 AM CDT Tue Apr 22 2025 Low stratus has built across the region with MVFR to IFR ceilings. Patchy fog may also develop over portions of the southern Edwards Plateau and western Hill Country. Conditions improve back to VFR levels this afternoon. There may be a few weak low topped rain showers this morning otherwise rain chances are low end this afternoon. Better chances of scattered showers and storms will be expected this evening into tonight. There is low confidence with placement and timing of activity. Have elected to maintain the PROB30s featuring -TSRA tonight into Wednesday morning at each of the TAF sites. KDRT has the slightly earlier start as storms may approach the Rio Grande from Mexico by around 00Z. Low stratus otherwise returns overnight with MVFR to IFR ceilings. Winds will generally remain light to moderate from the east-southeast and southeast through the period. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 88 69 84 69 / 20 30 60 20 Austin Bergstrom Intl Airport 89 68 84 68 / 20 30 60 20 New Braunfels Muni Airport 88 68 84 69 / 20 30 50 20 Burnet Muni Airport 87 67 82 68 / 20 40 50 30 Del Rio Intl Airport 89 70 85 72 / 20 40 20 40 Georgetown Muni Airport 89 68 83 68 / 20 30 60 30 Hondo Muni Airport 88 68 84 68 / 20 30 40 20 San Marcos Muni Airport 88 68 84 68 / 20 30 60 20 La Grange - Fayette Regional 88 70 84 70 / 30 30 60 20 San Antonio Intl Airport 88 69 83 71 / 20 30 50 20 Stinson Muni Airport 89 70 85 71 / 20 30 40 10 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ Short-Term...Brady Long-Term...05 Aviation...Brady