931 FXUS65 KBOU 081021 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 321 AM MST Sun Jan 8 2023 .SHORT TERM...(Today and tonight) Issued at 315 AM MST Sun Jan 8 2023 Current conditions include upper level cloudiness moving into and across the CWA from the west. There is also a small batch of Stratus and fog over central Weld and west central Morgan Counties. Greeley is reporting 1/4SM in the fog. Temperatures have a decent range across the plains at this time. Areas in the drainage winds are in the 20s and lower 30s F. The rest of the plains are in the teens and single digits F. Upper ridging will continue to push eastward across the CWA today and this evening. The flow aloft will be pretty weak from the west, then southwest. By 12Z Monday morning, stronger northwesterly flow aloft is just getting into the western CWA. There is weak synoptic scale vertical velocity progged today into this evening. Weak downward motion follows overnight. The low level winds look to be pretty light today and tonight, mainly adhering to normal diurnal patterns. There is some upper level moisture for the CWA today and tonight. Models show some shallow low level moisture to get into the high mountains after midnight. As a result, the only pops, 10-30%s, will be in Zone 31. High temperatures today should be 0-2 C warmer than yesterday's highs. .LONG TERM...(Monday through Saturday) Issued at 204 AM MST Sun Jan 8 2023 A flat upper level ridge will be over the area on Mon with a sfc lee trough along the I-25 Corridor. Overall it will be a dry day with warmer temps. Readings across the plains will be in the 40s with lower to mid 50s around the Denver area. Cross-sections show gusty winds will occur over the higher terrain as cross-barrier flow is in the 30-35 kt range. By Tue, moisture will increase in WSW flow aloft over the higher terrain. Lapse rates will become more unstable by aftn so expect an increase in snow showers over those mtn areas favored by a WSW orographic component. Across the plains it will be dry with highs ranging from the mid 40s in snow covered areas with 50's where snowpack is less. Winds will remain gusty over the higher terrain. For Tue night into Wed, a fast moving storm system will move across the area. This system has favorable QG ascent and lapse rates with it. As a result should see snow in the mtns with a good chance of rain and snow showers at lower elevations. Looking ahead to Thu and Fri, an upper level ridge will build into the area. This will allow for dry conditions and a warmer temperatures by Fri as readings rise into the 50's over nern CO. && .AVIATION...(For the 12Z TAFS through 12Z Monday morning) Issued at 321 AM MST Sun Jan 8 2023 South-southwesterly winds are expected to continue at DIA into the early afternoon hours today. Models then show some weak east or southeasterlies through around 01Z in the evening. Then it is back to drainage winds Sunday evening into Monday morning. There will be no ceiling issues. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...RJK LONG TERM....RPK AVIATION.....RJK