Area Forecast Discussion
Issued by NWS Austin/San Antonio, TX
Issued by NWS Austin/San Antonio, TX
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340 FXUS64 KEWX 272322 AFDEWX Area Forecast Discussion National Weather Service Austin/San Antonio TX 622 PM CDT Sat Apr 27 2024 ...New AVIATION... .SHORT TERM... (Tonight through Sunday night) Issued at 243 PM CDT Sat Apr 27 2024 Key Points * Isolated to scattered strong to severe storms overnight into early Sunday, mainly along and west of Interstate 35. * All hazards possible, including large (possibly very large, greater than 2 inch) hail, damaging winds, and a tornado or two. The latest radar data shows some weak showers ongoing from the southern Edwards Plateau eastward into the Hill Country and nearby I- 35 corridor. With some breaks in the clouds and continued heating, we could see a few storms develop this afternoon. However, chances are fairly low (20-30%). Gusty southeast winds continue this afternoon with wind speeds expected to stay just below Wind Advisory criteria (sustained 26 mph). Most of the evening hours should see convection remaining largely to our north. However, this will change as we head into the overnight hours as a Pacific cold front and upper level trough axis approach from the west. We should see a line of convection develop along and ahead of the front as the boundary encounters plenty of low-level moisture. While the stronger forcing for ascent remains north of our region, we could still see some strong to severe storms develop early Sunday morning. Timing may have trended just a little slower, but not by much and the inherited forecast had this covered. Forecast soundings still show favorable CAPE and wind shear, with all modes of severe weather possible. This includes large (possibly very large, greater than 2 inches in diameter) hail, damaging winds, and a tornado or two. SPC continues to show the higher risk for severe weather for areas generally west of the I-35 corridor. As the line of convection moves closer to the I-35 corridor Sunday morning, most of the hi-res models show a gradual weakening trend as convection moves well ahead of the Pacific front. We will need to keep an eye on the possibility of some convection re-developing late tomorrow afternoon, with a low end chance for severe storms along and north of I-10. Suspect the better chance for additional development Sunday afternoon will largely remain farther north from central into northeast Texas. && .LONG TERM... (Monday through Saturday) Issued at 221 PM CDT Sat Apr 27 2024 The mid-level pattern remains active as we move into the start of next week as west-southwesterly flow aloft remains in place through the beginning of May. There are some notable differences in overall precip amounts between ensemble members through the period, but for now, we will hope for continued rainfall, which will hopefully help to fill up some of our parched reservoirs. PWAT`s are expected to steadily increase through midweek as low level moisture refuses to budge. Whether we can actually squeeze some decent rains out of this moisture remains to be seen. The dryline should remain west of our CWA starting Tuesday as southwesterly flow aloft takes hold of the synoptic pattern. Warm, humid mornings, followed by mild and muggy afternoons will become the norm through at least late week with a chance for rain and isolated storms for most locations Tuesday- Friday. By Friday night, a cold front will attempt to move into the area from the north, something that will become increasingly rare as we move into the month of May. If this were to move through the region, we`d certainly have some decent upper level support to force widespread showers and isolated storms to develop over the region next Saturday. For now, we will stick with the NBM PoPs and run with it as it`s become difficult to pin down timing of precip this upcoming week. && .AVIATION... (00Z TAFS) Issued at 610 PM CDT Sat Apr 27 2024 VFR flight conditions for the next few hours across the I-35 TAF sites (KAUS, KSAT, KSSF) until ceilings lower into MVFR range this evening through the overnight. KDRT remains VFR through at least through midnight. A line of convection should develop later on tonight with the activity advancing through Del Rio after midnight and through the I-35 TAF sites (KAUS, KSAT, and KSSF) sometime early Sunday morning near or just after daybreak. Storms could be strong with strong winds and perhaps some potential for hail. Have elected to highlight a TEMPO group with -TSRA and gusty variable winds when convection moves across each of the TAF sites. The activity will be expected to diminish into Sunday afternoon with MVFR ceilings improving to VFR levels. The south-southeasterly winds remain breezy ahead of the line of convection with gusts up to 25 to 30 knots. Outside of any convective influences, the winds decrease behind the line of storms and may shift/become variable into Sunday evening. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 70 82 68 88 / 60 80 10 10 Austin Bergstrom Intl Airport 70 82 68 87 / 40 80 20 20 New Braunfels Muni Airport 71 83 68 88 / 40 70 10 20 Burnet Muni Airport 66 81 65 86 / 80 60 10 10 Del Rio Intl Airport 69 94 67 96 / 50 0 0 10 Georgetown Muni Airport 69 81 66 87 / 70 80 10 10 Hondo Muni Airport 68 87 66 90 / 60 60 10 20 San Marcos Muni Airport 70 82 68 87 / 40 70 20 20 La Grange - Fayette Regional 72 83 70 85 / 10 80 50 30 San Antonio Intl Airport 70 84 69 88 / 50 70 10 20 Stinson Muni Airport 72 85 70 88 / 40 70 10 20 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ Short-Term...Platt Long-Term...MMM Aviation...Brady