777 FXUS64 KEWX 160550 CCA AFDEWX Area Forecast Discussion...CORRECTED National Weather Service Austin/San Antonio TX 1250 AM CDT Sun Oct 16 2022 ...New AVIATION... .UPDATE... Issued at 755 PM CDT Sat Oct 15 2022 Elected to add some patchy fog across the coastal plains from late overnight into Sunday morning. Additionally, with a slightly faster timing of the cold front across the region Sunday evening/night, I have elected to lower the temperatures during Monday for areas that are mainly located along and north of the I-35 corridor, where the temperatures will fall into the upper 50s and low to mid 60s by the late afternoon. Kept rain chances the same as the previous package at this time. && .SHORT TERM... (Tonight through Sunday night) Issued at 157 PM CDT Sat Oct 15 2022 Synopsis/Mesoanalysis: Split flow continues to prevail over much of the CONUS. The northern stream, associated with an upper disturbance centered just to the southwest of Hudson Bay, swings east-southeast from the northern Rocky Mountains into the Ohio and Tennessee River Valleys. The accompanying southern stream speed max spreads zonally from the base of a cutoff low centered off the Baja California coastline into the lower Mississippi Valley and central Gulf Coast. The two features will continue to persist through tomorrow afternoon and evening, likely beginning to interact to some extent from the southern Plains east into the southeastern US. In the lower levels, a baroclinic zone is evident across central Oklahoma east into the Ozark Plateau. The boundary should serve as a focus for convective initiation across this region later today, with attendant outflows driving the front into the Edwards Plateau through tomorrow morning and afternoon. Tonight: Have largely removed previous slight chance mentions of showers and thunderstorms predawn over portions of the Rio Grande Plains and southern Edwards Plateau. The impulse which will facilitate activity should track largely north and west of the region, keeping precipitation chances confined mostly to the MAF and SJT CWAs. An isolated shower or storm can't be completely ruled out over far northern Edwards and Val Verde Counties, where a sliver of precip probabilities remain. The vast majority (if not all) of the area will remain dry, with low stratus developing nocturnally once again. Lows should thus remain in the upper 60s and low 70s across the area. Tomorrow: Expect highs in the 80s and low 90s. Thanks in large part to outflow from tonight's convection over the Red River Valley and ArkLaTex, the cold front mentioned above will begin to approach from the north by late afternoon/early evening. Likely due to 1) stubborn low stratus in the morning and 2) residual mid-upper level cloud debris from overnight and early morning thunderstorms to our north, convection allowing models continue to suggest little PM surface destabilization and attendant shower/storm development along the front as it approaches. Have thus trimmed precip probabilities back through sunset in light of these trends, though an isolated thunderstorm can't be entirely ruled out closest to the likely surface position of the boundary from the southern Edwards Plateau east into Hill Country. Have continued slight chance thunder mentions in these regions. Tomorrow Night: This continues to be a period that bears close watching. Convective development appears likely near and after 00Z over the lower Trans-Pecos as the speed max connected to the Baja cutoff begins to overspread the region. Activity should spread east into the Rio Grande Plains and Winter Garden moving deeper into the overnight hours, with lighter/more scattered precip possible over Hill Country and the the I-35 corridor. The cold front will concurrently be approaching and entering the southwestern CWA. Combined with nocturnally-amplifying east to southeast low level flow and attendant moisture advection, the forcing from the front and any impulses embedded within the mid level speed max could create a favorable setup for multiple episodes of convection over portions of the Rio Grande Plains and Winter Garden through the predawn hours Monday. Given the presence of 1.50-2.00" precipitable water values pooled along the front, as well as a nearly antiparallel alignment between the low and mid level flow, heavy rainfall and backbuilding/training would be possible in said setup. Lots of model spread continues to exist regarding accumulations, particularly between the CAMs and global ensembles, so we will refrain from suggesting any specific totals in this discussion. WPC has included much of the Rio Grande Plains and portions of the Winter Garden in a slight risk in its D2 Excessive Rainfall Outlook in light of this potential. We will continue to closely monitor forecast trends and amend the forecast as necessary. && .LONG TERM... (Monday through Saturday) Issued at 157 PM CDT Sat Oct 15 2022 Active southwest flow aloft along with some forcing along a cold front will result in active weather along with a good chance of rainfall for portions of south central Texas. With a fairly shallow cold front near the surface and southeasterly winds initially in place around 850mb early Monday morning, scattered to numerous showers and thunderstorms are expected. The models continue to show the most favorable setup for rainfall will occur out west across the southern Edwards Plateau and Rio Grande plains. We will keep rain chances generally at or above 70% for the mentioned areas throughout the daytime hours on Monday. With marginal shear and instability in place, a strong to severe storm or two can't be completely ruled out mainly over the Rio Grande plains south of Del Rio. Gusty winds and marginally severe hail are the main concerns. In addition, some locally heavy rainfall may occur across the Rio Grande plains as moist southeast to easterly flow just above the frontal layer continues through most of the daytime hours. Farther east into the Hill Country and along/east of the I-35 corridor, the setup for heavy rainfall does not appear too favorable at this time. We do expect some scattered showers and storms, but forecast rainfall amounts will be significantly lower compared to values along the Rio Grande. For Monday night, northeasterly flow in the low-levels begins to deepen and this will result in drier and more stable air being advected into the region. We will begin to show much lower rain chances over our northern areas, with higher rain chances farther south into the Winter Garden region. In addition, the focus for any strong storms and locally heavy rainfall should be mostly south of our region by late evening. Most areas will remain dry on Tuesday as gusty northeast winds behind the cold front spread across all of south central Texas. Much cooler high temperatures are in store with highs only in the lower 60s to near 70s. Cloud cover will also decrease from north to south as the day progresses. Low temperatures for Tuesday night into Wednesday morning will be quite chilly with some upper 30s likely in the Hill Country and mainly 40s expected elsewhere. Surface high pressure remains over the area Wednesday and this will result in highs in the upper 60s to lower 70s. South to southwesterly winds in the low-levels return on Thursday and highs will rebound back into the lower 70s to lower 80s. Southerly flow in the low-levels continues to strengthen on Friday and Saturday, with temperatures getting back closer to climatological normals. && .AVIATION... (06Z TAFS) Issued at 1233 AM CDT Sun Oct 16 2022 VFR flight conditions continue for the next few hours before MVFR ceilings develop during the latter half of the overnight through Sunday morning. Could see some IFR ceilings briefly occur but the latest guidance came in a little less aggressive compared to the previous runs. Patchy morning fog could develop as well but is expected to primarily concentrate across the coastal plains. VFR conditions return into and through Sunday afternoon in advance of the approaching front. Light to moderate southeasterly to east- southeasterly winds prevail through the afternoon. Area rain and convective chances will then ramp up from Sunday evening into the overnight along and behind the cold front as it moves across the area. Winds will also shift and increase from out of the north- northeast behind the front. Additionally, expect for the ceilings to lower as well at least down into the IFR to MVFR range. Some minor reductions in visibility will also be possible. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 91 65 69 54 / 10 60 60 20 Austin Bergstrom Intl Airport 90 65 69 53 / 10 50 60 30 New Braunfels Muni Airport 92 67 71 55 / 10 50 60 40 Burnet Muni Airport 87 60 65 51 / 20 60 60 20 Del Rio Intl Airport 87 68 70 56 / 10 80 80 50 Georgetown Muni Airport 88 62 66 52 / 20 60 60 20 Hondo Muni Airport 92 70 72 55 / 10 60 70 60 San Marcos Muni Airport 91 67 70 53 / 10 50 60 40 La Grange - Fayette Regional 92 67 74 54 / 10 50 50 30 San Antonio Intl Airport 92 69 71 55 / 10 50 60 50 Stinson Muni Airport 93 70 73 57 / 10 50 60 50 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ Short-Term...Brady Long-Term...Platt Aviation...Brady