


Area Forecast Discussion
Issued by NWS Austin/San Antonio, TX
Issued by NWS Austin/San Antonio, TX
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441 FXUS64 KEWX 150615 AFDEWX Area Forecast Discussion National Weather Service Austin/San Antonio TX 115 AM CDT Tue Jul 15 2025 ...New SHORT TERM, LONG TERM, AVIATION... .KEY MESSAGES... - Flood Watch remains in effect until 1 PM Tuesday for the Hill Country, southern Edwards Plateau, and portions of the Rio Grande Plains and I-35 corridor. - Additional rainfall of 1-3 inches with isolated higher totals up to 6 inches possible mainly this morning. Additional river rises are possible. - Drier conditions mid to late week with slightly higher temperatures. && .SHORT TERM... (Today through Wednesday) Issued at 113 AM CDT Tue Jul 15 2025 As of about midnight Tuesday, scattered showers and storms associated with an MCV near the Mexican border were beginning to spread northward across the Rio Grande Plains and into the southern Edwards Plateau. This activity is tapping into an overlapping nocturnal intensification of the 850mb low level jet, which is enhancing convergence within a plume of moist air with precipitable water values nearing and exceeding 2 inches, corresponding to values above the 90th percentile for this time of year. Additional showers and storms are expected over the course of the early morning hours, with some of the high-resolution models showing a gradual spread of the rain envelope into the western Hill Country. Boundaries left behind by storms earlier in the evening may also concentrate additional downpours along north-to-south lines. The modeled atmospheric conditions indicate an environment continuing to favor efficient rainfall, leading to high rain rates which could locally reach 2 inches per hour at times. The 00Z HREF LPMM indicated the highest rain totals through this morning could approach 6 inches in localized spots as showers continue to stream northward. Much of Tuesday morning`s rains will be falling atop sensitive soils already moistened heavily by Monday morning`s rains, leading to an increased potential for runoff which could trigger flash flooding. Given these factors, it is prudent to be weather aware and have multiple methods of receiving weather warnings. Southwesterly deep-layer flow should cause the overall area of heavy rain showers and storms to gradually continue northeast during the morning along with the MCV. Evolution of the MCV itself is uncertain, though most models move its associated vorticity northward. There should be a general decrease in the intensity and coverage of rain late-morning and afternoon as the low-level jet weakens. However, rains may continue to be enhanced near the MCV as it drifts out of our area and draws in more unstable air. Most of the high-resolution guidance has the MCV out of the CWA by Tuesday evening with a subsequent decrease in rain chances over the area, though there could be some reinvigoration of isolated showers with daytime heating over South-Central Texas towards the late afternoon and early evening. As we head into Tuesday night into Wednesday, the growth of subtropical ridging centered over the lower Mississippi Valley is forecast to nudge the corridor of moist air and convergence farther to the west, displacing it away from the Gulf and leading to a reduction in moisture and rain chances. Wednesday looks dry for most, though ridging appears relatively weak and could allow for an isolated shower or storm accompanying onshore flow/seabreeze over the Coastal Plains. && .LONG TERM... (Wednesday night through Monday) Issued at 113 AM CDT Tue Jul 15 2025 Continued extension of the mid- to upper-level Gulf coast ridge into our area should generally support an increase in daytime temperatures during the mid to late week with mostly dry conditions. While medium-range ensembles show a summertime ridge pattern developing over the course of the week, we are monitoring a tropical disturbance currently offshore the eastern coast of Florida. As the ridge builds, this disturbance could track west along or parallel to the northern US Gulf coast during the latter part of the week. Most of the model guidance does not bring this feature as far west as our area, though it will be worth keeping an eye on. Aside from this disturbance, which could stick around into the weekend, there is good consensus from ensemble guidance that the broader ridging pattern holds through the weekend and into Monday with near average temperatures. && .AVIATION... (06Z TAFS) Issued at 113 AM CDT Tue Jul 15 2025 VFR conditions prevail across area terminals as of 06Z, but shortly that changes into MVFR category as a low cloud deck develops. By 07Z, MVFR cigs are forecast for the I-35 sites and remain through at least 15Z Tuesday. MVFR cigs are expected to affect the KDRT around 13Z, however, showers and storms could be affecting the site with cigs coming up and down overnight. VFR conditions return by 16Z for the I-35 airports and by 19Z for KDRT. A southerly flow around 5 to 10 knots is forecast to dominate overnight across the terminals with speeds increasing late Tuesday morning to 10 to 15 knots with gusts of 20 to 25 knots. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 94 76 96 74 / 10 0 0 0 Austin Bergstrom Intl Airport 94 75 96 74 / 10 0 0 0 New Braunfels Muni Airport 95 75 97 73 / 10 0 0 0 Burnet Muni Airport 91 73 92 71 / 20 10 0 0 Del Rio Intl Airport 91 77 96 76 / 30 10 0 0 Georgetown Muni Airport 93 74 94 72 / 10 0 0 0 Hondo Muni Airport 92 74 96 72 / 30 10 0 0 San Marcos Muni Airport 94 74 97 72 / 10 0 0 0 La Grange - Fayette Regional 93 75 94 74 / 10 0 0 0 San Antonio Intl Airport 94 77 96 74 / 10 10 0 0 Stinson Muni Airport 96 77 98 74 / 10 10 0 0 && .EWX WATCHES/WARNINGS/ADVISORIES... Flood Watch until 1 PM CDT this afternoon for Bandera-Bexar-Blanco- Burnet-Comal-Edwards-Gillespie-Hays-Kendall-Kerr-Kinney-Llano- Maverick-Medina-Real-Travis-Uvalde-Val Verde-Williamson-Zavala. && $$ Short-Term...Tran Long-Term...Tran Aviation...17