National Weather Service Forecast Discussion |
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807 FXUS65 KBOU 140036 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 536 PM MST Sat Dec 13 2025 .KEY MESSAGES... - Cooler for northeast plains this weekend. Otherwise, continued mild and dry across the region through early next week. - Strong downslope winds expected Wednesday, which may lead to fire weather concerns for the lower elevations and foothills. - Increased potential for mountain snow late Wednesday into Thursday. && .SHORT TERM /Through Sunday/... Issued at 249 PM MST Sat Dec 13 2025 Cold front has backed southwest across the northeast plains and urban corridor this afternoon. Temperatures reached the lower to mid 60s across much of the urban corridor before falling in the mid 40s to lower 50s after the frontal passage. Over the far northeast corner of Colorado, temperatures remained in the 20s most of the day with foggy conditions. The fog will linger much of the night here over the far northeast corner. The cold arctic high off to the east will continue to move away from Colorado. The pressure gradient shifts to a south to southwest low level flow that will scour the colder air out late tonight and Sunday. The colder air may hang on for a good part of the day over the northeast plains, but eventually expect temperatures to climb into the 40s to mid 50s. Farther west, along the urban corridor, temperatures should reach the lower 60s during the afternoon hours. && .LONG TERM /Sunday night through Saturday/... Issued at 249 PM MST Sat Dec 13 2025 Above normal temperatures are expected each day of the week this week, along with the potential for another high wind event midweek and elevated fire weather concerns. Most of the area will remain dry, aside from orographic snow showers in the northern mountains. The beginning this week will be relatively quiet, as we will be situated under an upper level ridge. Multi-run ensemble solutions have continued to indicate maximum temperatures between the high 50s to low 60s across the plains and 30s/40s in the mountains/valleys. With the combination of relative humidity values around 20% and breezy winds off the Cheyenne Ridge, brief periods of elevated fire weather conditions are possible across the northern plains. Winds should stay relatively weak across other portions of the forecast area, which will keep fire weather concerns at bay. Weather begins to pick up on Wednesday, as flow aloft increases with a shortwave trough trekking across the northern United States. Confidence is increasing of strong winds impacting the high country and possibly adjacent plains. However, it is too soon to go into specifics, as there are still discrepancies between models in terms of ingredients for strong winds to reach down to the foothills. We will continue to monitor the evolution of the shortwave that will be north of us, as that will dictate if our flow aloft is more zonal or northwesterly. Regardless, expect a windy day across the forecast area, with NBM indicating a 60% for wind gusts >70 mph for the Front Range mountains, and a 40-50% for gusts >50 mph at times along the foothills. Even if relative humidity values stay marginal (20-25%), strong winds will allow elevated to briefly critical fire weather conditions across the foothills and plains. As for precipitation, our northern mountains may receive orographic snow showers Wednesday into Thursday morning. However, minimal accumulations are expected, as there will not be a lot of moisture in our area. Park Range will likely receive the most snow, with ensemble solutions indicating