337 FXUS64 KSJT 142027 AFDSJT Area Forecast Discussion National Weather Service San Angelo TX 227 PM CST Mon Dec 14 2020 ...New LONG TERM... .SHORT TERM... (This evening through Tuesday) Issued at 1203 PM CST Mon Dec 14 2020 Early this afternoon, visible satellite shows mostly sunny skies across West Central Texas, with just a few to scattered high clouds occurring. On water vapor satellite, an upper level trough was moving into the Great Basin, with plentiful upper level moisture streaming up from the south ahead of the trough axis. At noon today, temperatures in the Big Country were 5-10 degrees warmer than 24 hours ago (sunnier skies today compared to cloudy skies yesterday), while elsewhere temperatures were 5-15 degrees cooler (due to the cold front having moved through the region, while 24 hours ago the front was north of the area). With the post-frontal cold airmass in the region, expect highs today in the upper 40s to mid 50s. The trough will continue to move east into the Central to Southern Plains tonight through Tuesday, bringing increasing high clouds to the region. The deeper moisture associated with this trough looks to stay north and east of the region, so no rain is expected for us. As the upper level trough moves in, surface low pressure will develop in east-central NM late tonight/early Tuesday morning, then move east-southeast through West Central Texas mid to late Tuesday morning, with an associated front bringing dry (dewpoints decreasing to the low to mid 20s) and gusty westerly winds (around 15-20 mph with gusts to 30 mph) behind it, while some increase in low level moisture ahead of the front will result in low cloud development... mainly east of a Haskell to Junction line. These clouds should dissipate by late morning as the dry air behind the front continues to push east. Breezier winds and increased clouds overnight should inhibit radiational cooling, so expect it to be warmer tonight compared to this morning (lows tonight in the low to mid 30s). Drier air and slight warming of the 850 mb thermal ridge, should result in slightly warmer highs Tuesday (highs in the mid 50s to low 60s) except in the Big Country where cloudy skies may linger longer (highs in the mid to upper 40s). && .LONG TERM... (Tuesday night through next Monday) Issued at 219 PM CST Mon Dec 14 2020 Lingering cloud cover over the Big Country early Tuesday evening will clear out, as the upper system lifts east/northeast out of the southern Plains. Gusty northwest winds Tuesday evening will diminish overnight, as surface high pressure builds into West Texas. Temperatures will be colder Tuesday night, with overnight lows in the 20s to around 30 degrees. Wednesday will be sunny but cool, with highs ranging from around 50 in the northeastern Big Country, to the mid 50s across the Concho Valley and southern part of our area. Surface high pressure will shift east across our area on Wednesday, and into east-central and south-central Texas Wednesday night. Another cold night for Wednesday night with clear skies, dry air and light winds for most of our area. Expect overnight lows to be in the mid to upper 20s for much of our area, with a few lower 20s possible in the favored low-lying areas of the Heartland and Northwest Hill Country. Light south winds developing overnight should limit the lows to 30-32 across the western and southern Big Country. Thursday will be warmer with increasing south winds, as a lee surface trough develops to our west and pressure gradient increases. An upper trough will move east across the Great Basin on Thursday, and will extend from the central Rockies into the southwestern states by Friday morning. The warming trend will continue for our area Thursday night into Friday, with breezy south winds. Lows Thursday night are expected to be 35-40, with highs Friday mostly in the mid 60s. The aforementioned upper trough is progged to continue moving east into the southern Plains and Texas, with associated cold front moving south across our area Friday night. Saturday will be dry and cooler, but this cold front will be weaker than the Tuesday front. Highs Saturday are expected to range from the mid 50s across the Big Country, to the lower 60s south of I-10 and in our far southeastern counties. The weekend into the beginning of next week looks dry for our area, with highs increasing to the mid 60s to around 70 by Monday. && .AVIATION... (18Z TAFS) Issued at 1112 AM CST Mon Dec 14 2020 VFR conditions should continue through 07Z Tues, then MVFR CIGs likely to develop east of a Haskell to Junction line between 07Z Tues and 14Z Tues. KBBD is likeliest to be impacted, while for now, confidence was a bit too low for KJCT and KABI to put MVFR conditions in their TAFs. Elsewhere, VFR conditions likely to continue. 14Z Tues to 18Z Tues, any MVFR conditions likely to gradually improve to VFR except possibly in Haskell and Throckmorton counties. S to SE winds of 5-9 KT will continue through 15Z Tues, then SW to W winds of 12-16 KT with gusts of 19-25 KT will develop. && .PRELIMINARY POINT TEMPS/POPS... Abilene 35 50 26 51 / 5 5 0 0 San Angelo 35 59 25 55 / 0 0 0 0 Junction 35 63 26 56 / 0 0 0 0 Brownwood 34 58 27 52 / 5 5 0 0 Sweetwater 34 49 27 52 / 5 0 0 0 Ozona 34 58 27 55 / 0 0 0 0 && .SJT WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...SJH LONG TERM....19 AVIATION...SJH