National Weather Service Forecast Discussion |
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207 FXUS65 KBOU 151129 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 429 AM MST Mon Dec 15 2025 .KEY MESSAGES... - Warm and dry through Tuesday, with breezy conditions tonight into Tuesday for the foothills and mountains. - Remaining warm Wednesday with strong winds expected west of I-25, and light mountain snowfall later in the day. Near- critical fire weather conditions possible near the base of the foothills. - Strong winds will be more widespread Wednesday night and Friday, impacting lower elevations. Friday may see critical fire weather conditions across portions of the plains and urban corridor. - This weekend: Mild and dry for the lower elevations, which snow potentially returning to the mountains. && .SHORT TERM /Through Monday/... Issued at 213 PM MST Sun Dec 14 2025 Upper level ridging over Colorado flattens during the day Monday as northwest flow aloft begins to increase. For tonight, west winds in the higher foothills and Front Range Mountains increase, with gusts to 40 mph possible. Elsewhere, we are looking at relatively light winds. Temperatures in the mountain valleys and lower lying areas across the plains will be cooler spots, with lows in the teens and lower 20s. On Monday, it will be mild again with temperatures well above normal. High across northeast Colorado will reach the upper 50s to mid 60s. Cross sections show some high level moisture, mainly during the morning, with decreasing high clouds during the afternoon. Expect for those typical breezy locations in the foothills and mountains, light winds will prevail Monday. && .LONG TERM /Monday night through Sunday/... Issued at 213 PM MST Sun Dec 14 2025 The flow aloft will become more WNW on Tue with cross-sections showing only some mid and higher level moisture embedded in the flow. With downslope flow over the area, highs will remain well above normal with a few record highs possible at lower elevations. On Wed, an upper level trough will move across the area late in the aftn thru Wed night. Cross-sections show increasing moisture in the mtns by Wed evening with favorable orographic flow. In addition, a rather stg upper level jet will move into the area which may lead to some heavier banded snowfall in some mtn areas. In addition, it will be very windy as well. At lower elevations, downslope low level flow will remain in place thru the aftn, with dry conditions along with another day of record highs possible around the Denver area. Meanwhile, a bora type front will move across nern CO by late aftn into the evening hours. As a result, may see strong winds develop across portions of the foothills and plains as this feature moves across. For Thu into Thu night, the flow aloft will continue WNW with some moisture embedded in the flow. May see orographic light snow continue in the nrn mtns mainly Thu aftn and night. At lower elevations it will be dry and windy with highs dropping back to more seasonal levels. Looking ahead to Fri, the flow aloft will become more westerly. This will lead to dry conditions along with warmer temperatures as downslope flow redevelops. By Sat, another fast moving system may affect the area bringing a chc of snow to the mtns with another round of wind at lower elevations. && .AVIATION /12Z TAFS through 12Z Tuesday/... Issued at 414 AM MST Mon Dec 15 2025 VFR conditions will prevail for all terminals through the TAF period. A weak Denver cyclone is expected to develop again this afternoon near Denver proper, favoring SE winds for KDEN before a return to drainage flow this evening. && .FIRE WEATHER... Issued at 414 AM MST Mon Dec 15 2025 Elevated to near-critical fire weather conditions will be in place in the foothills through tonight, with elevated fire weather conditions across the Cheyenne Ridge Tuesday. Stronger winds on Wednesday will lead to near-critical fire weather conditions for the lower foothills and adjacent urban corridor, mainly west of I-25, despite some moderation in humidity. Potential for critical fire weather conditions will return to portions of the lower elevations on Friday with the arrival of warmer, drier and continued breezy conditions. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM.....12 LONG TERM......RPK AVIATION...BRQ FIRE WEATHER...BRQ