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070 FXUS65 KBOU 230553 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1053 PM MST Sat Nov 22 2025 .KEY MESSAGES... - Another light precipitation event is possible Sunday and Sunday night, with light snow above ~7,000 ft and light rain lower elevations. - Becoming windy Monday to Tuesday, and turning colder. - Some moderation with diminishing chances of any snow through Thanksgiving. && .DISCUSSION /Through Saturday/... Issued at 257 PM MST Sat Nov 22 2025 Shortwave ridging over Colorado has brought dry conditions and slightly above normal temperatures over the forecast area for the day. With relatively light winds aloft, expect a quiet night ahead of an approaching system. Models are in good agreement of an upper level low trekking across the forecast area Sunday afternoon/evening, with the trough axis centered over east central Colorado. Due to this track, the best areas for measurable precipitation will be the southern Front Range mountains and southern/eastern plains. Ensemble`s 25th-75th percentiles range between 0.1"-0.4" of QPF, but can`t rule out a narrow band of localized higher amounts due to frontogenetical forcing under the deformation zone. Recent ensemble and deterministic runs have continued to trend downwards in precipitation across the northern Front Range mountains and northern I-25 corridor- have lowered PoPs Sunday through Monday for that reason. In terms of precipitation type, rain is expected for elevations below 7,000 ft. Snowfall amounts will most likely range from T-4", with highest amounts confined to the high passes. Areas along and south of I-70 will see slick roads Sunday evening and into Monday morning. By Monday afternoon, flow aloft will turn west/northwesterly as a fast-moving upper level shortwave crosses just north of the forecast area. This system could bring light orographic snow showers to the northern Front Range mountains, with minimal accumulation and travel impacts. However, the rest of the forecast area will likely remain dry due to the northerly track of the system. Model guidance has trended towards weaker cross-barrier flow, with only a couple of Sangster runs showing a 20% chance of winds reaching above 60 kts. We will continue to monitor model trends, but at this time no high wind highlights are expected. A potent cold front associated with the upper level system will travel across the forecast area Monday night and into Tuesday morning. Morning lows will range from 20s to the low 30s along the plains and teens to low 20s in the mountains and valleys. Wednesday morning temperatures are expected to be colder, with most of the plains in the mid teens-low 20s and mountains and valleys ranging from single digits to mid-teens. A warming trend will return for Thanksgiving and Friday as flat ridging settles over the southwestern United States. Cross-barrier flow could create windy conditions along the higher terrain, however expect generally mild, albeit quiet weather days late this week. The only exception would be if an embedded shortwave crosses the state, which would bring orographic snow showers to the northern mountains. Towards the end of the holiday weekend, ensemble guidance has continued to indicate a disturbance bringing colder temperatures and a chance of our first snow showers to the plains. However, there are still many discrepancies between model runs on exactly how this system will evolve. We will continue to monitor any changes in guidance. && .AVIATION /06Z TAFS through 06Z Monday/... Issued at 1052 PM MST Sat Nov 22 2025 Normal drainage winds are expected overnight with no ceiling issues. On Sunday, a surge of cooler air is expected to move across DIA late in the morning with weak upslope flow behind it. Ceilings could lower into the BKN030-060 range by late Sunday afternoon and on into the evening. Visibilities could lower to 3SM with -RA. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...MAI AVIATION.....66