692 FXUS65 KPUB 191726 AFDPUB Area Forecast Discussion National Weather Service Pueblo CO 1126 AM MDT Tue Oct 19 2021 .UPDATE... Issued at 1006 AM MDT Tue Oct 19 2021 Have ended the High Wind Warning a little early, as gusts over the southern Sangres have been trending downward below 50 mph the past couple hours, and models suggest any mountain wave has been overwhelmed by increasing forward shear as upper level jet moves across. && .SHORT TERM...(Today and tonight) Issued at 356 AM MDT Tue Oct 19 2021 ...Red Flag conditions Southeast Plains this afternoon... Upper low over northern UT will continue to lift north northeastward across northern CO/southern WY today. Band of snow has spread into the Continental Divide early this morning with CPW reporting visibilities below 1 mile with winds gusting to around 60 mph as of 09z. Have seen an intermittent wind signature in KPUX radar to the lee of the Wet mountains where PSF3 Canon City RAWS has reported gusts to around 50 mph at 11.5kft. So far gusts across the southern Sangres have stayed around 50 mph or below as of 09z. HRRR and NAMNest both indicate the possibility for a brief period of high wind criteria across the southern Sangres peaking around 10-16z. This which remains fairly high in elevation, at or above 10kft. This stems from a brief window for mountain wave development ahead of the mid level front which crosses the mountains between 12z and 15z which brings some increasing downward forcing and potential for mixing 50 kt winds down to the surface. Again think this will stay confined to the higher areas of the southern Sangres and will maintain current high wind warnings through 18z. Meanwhile snow across the Continental Divide and northern Sangres will peak this morning then decrease through mid morning before increasing again in coverage across the central mountains during the afternoon as flow aloft shifts from the northwest and a round of wrap around precipitation spreads into the central mountains north of highway 50. Additional accumulations of an inch or two will be possible across the southwest this morning and central mountains through today, before the event winds down quickly this evening. Across the plains, dry air spills eastward over the mountains behind a bora front, and in spite of the cooler temperatures coming in aloft with the upper low, deep mixing and gusty winds will lead to more widespread critical fire weather conditions across the plains during the afternoon. Current Red Flag Warnings still look on track. While the southern portions of northern El Paso county could see a couple hours of humidity below 15 percent, higher humidity values working in from the north late in the period should bring humidity values up again, so will hold off on expansion of the Red Flag Warnings. The system pulls off to the northeast overnight with clearing skies and decreasing winds. This will set the stage for a colder night across southern CO with temperatures dropping back down to around or below freezing for most of the lower elevations, and teens and 20s across the valleys and mountains. All areas have experienced a season ending hard freeze so no freeze warnings will be issued. -KT .LONG TERM...(Wednesday through Monday) Issued at 356 AM MDT Tue Oct 19 2021 Wednesday-Friday...Northwest flow aloft moderates across the Rockies on Wednesday, and becomes more westerly but remains generally weak through the end of the work week, as upper level ridging builds across the region. This will allow for dry conditions and generally light winds to prevail across the region through Friday. A warming trend also remains in the offing, with temperatures near seasonal levels in the 60s across the plains and in the 40s and 50s across the higher terrain on Wednesday, warming back to above seasonal levels in the 70s across the plains and in the 50s and 60s across the higher terrain, by Friday. Saturday-Monday...Models continue to indicate upper level ridging flattening across the Rockies with faster zonal flow developing across the Northern Tier of States and persisting into early next week. Latest models continue to differ on how fast and how far south eastern Pacific energy moves through the flow, with the GFS and the GEFS ensemble mean faster and further south than the ECMWF and the EPS ensemble mean. With the model differences, have stayed with the blended model solution which brings in slight pops across the higher terrain of Colorado late Saturday night through the day Monday. NBM also keeps temperatures above seasonal levels into early next week. At any rate, the increasing flow aloft will lead to breezy to windy conditions developing across the area once again, and will lead to increasing fire danger into early next week. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1121 AM MDT Tue Oct 19 2021 VFR at all sites the next 24 hrs. At KALS, w-sw winds will gust near 30 kts at times this afternoon, the diminish this evening. At KCOS and KPUB, west winds this afternoon will gust over 30 kts, then shift to the north and remain gusty after 23z-00z behind a cold front dropping south through the plains. Winds then diminish overnight into Wed morning. && .PUB WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 7 PM MDT this evening for COZ222-227>237. && $$ UPDATE...PETERSEN SHORT TERM...KT LONG TERM...MW AVIATION...PETERSEN