170 FXUS64 KSJT 261131 AFDSJT Area Forecast Discussion National Weather Service San Angelo TX 531 AM CST Thu Dec 26 2019 .AVIATION... /12Z TAFS/ IFR ceilings and visibilities are occurring for most locations across West Central Texas, with visibilities at or below one quarter mile. Conditions will fluctuate frequently this morning, before improving by early afternoon. Ceilings are expected to fall back to IFR again overnight tonight. SK && .PREV DISCUSSION... /issued 326 AM CST Thu Dec 26 2019/ SHORT TERM... (Today and Tonight) The post-holiday foggy blues appear to be setting in across parts of the Hill Country, Concho Valley, and Edwards Plateau this morning. Visibilities in some locations will fall below one quarter mile, so a Dense Fog Advisory was issued through 9am. Otherwise, conditions are far different from this time yesterday morning, as temperatures are holding in the 40s to low 50s. Dewpoint temperatures are also higher, especially across the Hill Country. These conditions were advected in during the day yesterday by southeast winds in advance of a developing area of low pressure over the Central and Southern High Plains. This appears to be just a pre- cursor to the next system that will affect west Texas, which is an upper low currently located just off of southern California. This feature will move across the Desert Southwest over the next 24 hours while moisture should remain in place across West Central Texas. However, moisture will be very shallow today and this evening, which should just maintain cloud cover across west Texas. As the night goes on, better lift should occur with this system, allowing for light rain showers to develop and increase in coverage overnight. Rainfall amounts will be very light, with the potential for drizzle and additional fog early tomorrow morning. Otherwise, temperatures will be held to the mid 60s today, and in the low to mid 50s tonight, due to the cloud cover across the area. Many areas will probably reach their high temperatures for a brief time this afternoon with any breaks in the stratus that occur. LONG TERM... (Friday through Wednesday) On Friday, an upper level trough will be located across the Desert Southwest. Ahead of this feature extensive cloud cover is forecast across West Central Texas, with isolated to scattered light showers possible. Highs on Friday will be in the mid to upper 60s. The better chance of showers and isolated thunderstorms will be Friday night into Saturday morning, as the upper level trough approaches and a Pacific front sweeps through the region. Rainfall amounts will generally be around a quarter inch or less, with localized higher amounts possible. Rain chances will quickly end from west to east on Saturday behind the cold front. Gusty west winds of 10 to 20 mph will usher in much drier air Saturday afternoon. A surge of cooler air will move through the region Saturday night into Sunday morning, as the upper level trough departs the area. This will result in cooler temperatures Sunday through the middle of next week. Highs will generally be in the mid 50s to lower 60s, with overnight lows in the upper 20s to mid 30s. The next upper level trough/low is forecast to dig south toward Baja California early next week. Model discrepancies continue on the eventual track and timing of this feature. Given the uncertainty, kept PoPs in the slight chance/chance category Tuesday through Thursday. && .PRELIMINARY POINT TEMPS/POPS... Abilene 64 54 66 50 / 0 20 20 70 San Angelo 65 54 68 47 / 5 30 30 70 Junction 67 55 69 48 / 10 10 20 50 Brownwood 66 54 68 49 / 0 10 10 60 Sweetwater 62 55 64 49 / 5 30 40 80 Ozona 62 53 65 46 / 10 30 30 80 && .SJT WATCHES/WARNINGS/ADVISORIES... Dense Fog Advisory until 9 AM CST this morning for Brown- Callahan-Coke-Coleman-Concho-Crockett-Irion-Kimble-Mason- McCulloch-Menard-Runnels-San Saba-Schleicher-Shackelford- Sterling-Sutton-Throckmorton-Tom Green. && $$