015 FXUS64 KSJT 291127 AFDSJT Area Forecast Discussion National Weather Service San Angelo TX 627 AM CDT Tue Oct 29 2019 .AVIATION... /12Z TAFS/ IFR/LIFR ceilings will continue to impact all terminals over the next 24 hours. A large stratus deck has developed in the wake of the frontal passage. Ceilings will fluctuate all day but generally be in the 300 to 700 foot range. Intermittent -DZ and -RA will reduce visibilities to below 2SM. Amendments may need to be made to include the possibilities of -TSRA at some of terminals later this afternoon. && .PREV DISCUSSION... /issued 351 AM CDT Tue Oct 29 2019/ SHORT TERM... (Today through Wednesday Night) Unseasonably cooler temperatures today followed by a strong surge of very cold air Wednesday night.. The left over frontal boundary has stalled out across the area based on the latest surface analysis. A shallow dome of cold air is pushing up and over the boundary creating a widespread stratus deck across much of the area. Intermittent drizzle will mix with some light rain through the morning hours. By the afternoon the surface boundary will be slowly moving south as an upper level shortwave trough moves across northern Texas and the stratiform rain will transition to a more convective type rain as thunderstorms begin developing during the afternoon hours, mainly across the southeastern counties. Some elevated instability aloft should be enough to sustain a marginal severe threat with any elevated convection that does develop. These storms will pose a small hail threat. The main severe risk will be for any storms that manage to initialize along or ahead of the front in the warm sector and become surface based. These storms will pose the greatest risk for severe weather with small hail, damaging winds and heavy rainfall being the main hazards. Locations well displaced from the front will continue to see on and off light rain with an occasional rumble of thunder. The convective activity will diminish during the evening hours but we will continue to see the chance for light rain showers through the overnight hours. Highs will range from the lower 40s across the Big Country, to the 50s across the Concho Valley and Heartland, with temperatures in the 60s across the Interstate 10 corridor. Overnight lows will range from the mid to upper 30s to the north, to lower 50s to the south. As we head into Wednesday morning we will be tracking a strong area of low pressure pushing out of the Rockies with the associated strong cold front moving into western Texas. Both the EC and the NAM push the front through the area during the late morning hours and keeps daytime highs a few degrees removed from the the overnight low temperatures. The GFS model brings the front in later and allows for some dissipation of the clouds and some WAA advection to push temperatures into the 60s and 70s. The current forecast is a blend of these models in regards to temperatures but the timing of the front in this forecast lines up well with the EC and the NAM. Temperatures will range from the mid 40s to the upper 50s. As this strong cold front moves across the area, expect widespread showers with embedded thunderstorms to develop. Some of this rain could be heavy at times and some minor flash flooding could be possible under the heavier thunderstorm cores. The front will be east of our area by Wednesday night with rain chances ending from west to east. As the front pushes through, a strong northwest, downsloping wind will bring some very dry air into West Central Texas along with a strong surge of cold air. We have issued a Freeze Watch for late Wednesday night and into Thursday morning. Temperatures will fall into the 20s for most locations and a widespread freeze seems likely. This watch may be upgraded to a Freeze Warning in later forecast updates. An ongoing stiff northwest wind between 10 to 15 mph with gusts up to 25 mph will make for a wind chill temperature in the teens Thursday morning. LONG TERM... (Thursday through Monday) A strong surface high will be over the region Thursday, with continued post-frontal cold air advection occurring with the northerly low level flow. Thus, highs Thursday look to only be in the low to mid 50s. With weak winds and clear skies Thursday night/Friday morning, and the cold air mass over the region, expect a good radiational cooling setup, resulting in pretty cold overnight lows in the upper 20s to around 30. The return of warmer southerly low level flow on Friday should bring some warming, with highs Friday in the low to mid 60s. Another cold front is then forecast to come down Friday night into early Saturday morning. This looks like a dry cold front, and it is also a weaker front than what will come down on Wednesday. Forecast lows Saturday morning are in the low 30s, and highs Saturday are in the upper 50s to low 60s. Southerly flow returns again for Sunday and continues into Monday, resulting in some warming, with highs Sunday in the mid 60s and highs Monday in the low to mid 70s. Another cold front may come down Monday night, but this front again looks dry. && .PRELIMINARY POINT TEMPS/POPS... Abilene 44 39 45 26 / 50 70 60 10 San Angelo 54 46 53 28 / 50 70 60 10 Junction 62 53 59 31 / 40 70 60 30 Brownwood 45 41 50 29 / 60 80 60 10 Sweetwater 44 38 43 24 / 40 60 50 5 Ozona 61 52 58 30 / 40 50 50 10 && .SJT WATCHES/WARNINGS/ADVISORIES... Freeze Watch from late Wednesday night through Thursday morning for Brown-Callahan-Coke-Coleman-Concho-Crockett-Fisher-Haskell- Irion-Jones-Kimble-Mason-McCulloch-Menard-Nolan-Runnels-San Saba- Schleicher-Shackelford-Sterling-Sutton-Taylor-Throckmorton-Tom Green. && $$ 99/99/40