National Weather Service Forecast Discussion |
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061 FXUS65 KBOU 241747 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1047 AM MST Wed Dec 24 2025 .KEY MESSAGES... - Warm and dry through Friday, with the mountains seeing breezy conditions and a slight chance (20-40%) of light snow and rain/snow showers Thursday into Friday. - Increased fire danger Friday for the foothills and portions o the urban corridor, although humidity levels remain uncertain. - Light mountain snow expected Saturday, favoring the Park Range. - Cooler starting Saturday, with slim potential for precipitation for the lower elevations. && .UPDATE... Issued at 325 AM MST Wed Dec 24 2025 Main concern today is higher level cloud cover which could affect aftn highs. Model data isn`t in agreement as to how much cloud cover may linger thru the aftn hours over the plains. If clouds decrease by late morning into early aftn, highs may reach record highs in some areas. However, if the abundant cloud cover sticks around, then highs will likely stay blo guidance and end up similar to Tuesday. && .DISCUSSION /Through Tuesday/... Issued at 1259 PM MST Tue Dec 23 2025 Another warm afternoon today, though with a relatively pronounced north/south gradient over the urban corridor thanks to Denver cyclone-induced northerly flow keeping temperatures cooler to the north of the Denver metro. Will be much of the same story tomorrow, with highs 20-25 degrees above normal and continued dry conditions. Denver will flirt with its record daily high again (both forecast and record are 70F). The mountains will see slight cooling with greater cloud cover, but nonetheless will be mild. The ridge will remain anchored in place over the central plains on Christmas Day, and enhanced downslope flow will make for another likely record-breaking warm day with little change in temperatures. Marginally stronger flow aloft will provide for breezy conditions in our high country, but these won`t spread into lower elevations. Guidance has been consistently delaying the arrival of deeper moisture into the mountains, reducing the chance of any late-day showers to under 20% outside of the Park Range for Christmas. In fact, mountain snow potential isn`t overly impressive for Friday either, with a corridor of dry air at mid- levels oscillating over Colorado with some discrepancy as far as its exact positioning. With high country winds expected to peak Friday and producing leeside gusts 40-60 mph, there`s potential for near-critical fire weather conditions if the drier air surfaces in the afternoon. For the lower elevations, temperatures will relax slightly on Friday, but we`ll still warm into the 60`s. Models still suggest the upper-level low off the NorCal coast will push onshore Friday night, this favoring a period of increased moisture advection into the high country through Saturday as the trough approaches. The moisture plume does look to fizzle out slightly as it pushes southeast, lending greater confidence to a few inches of snow accumulation for the Park Range, and lower confidence elsewhere. Both GEFS and EC ensemble suites show quite similar QPF distributions, with a probability of exceeding 0.10" in 24 hrs of around 90% for the Park range, lowering to around 50% for the I-70 corridor. Those numbers drop to around 20% and 5% respectively when assessing probabilities of exceeding 0.50". All in all, not all that promising with respect to making more than a minor dent in our trailing snowpack conditions, however we may see some slick travel conditions for mountain passes. Meanwhile, the lower elevations will see a considerable cooldown Saturday with the passage of a cold front, with the cooler air being reinforced for Sunday when highs are expected to be near or even slightly below (yes, below!) normal. Chances for precipitation east of the mountains late Saturday into Sunday morning remain slim, with the bulk of guidance keeping a shortwave too far to our north, but there`s enough potential with the frontal push to sustain about 20% PoPs for the urban corridor, foothills and the Palmer Divide. Milder and dry conditions are favored as we enter into early next week. && .AVIATION /18Z TAFS through 18Z Thursday/... Issued at 1042 AM MST Wed Dec 24 2025 Weak normals diurnal wind trends can be expected at DIA this afternoon, tonight and into Thursday. There will be no ceiling issues. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...RPK DISCUSSION...BRQ AVIATION...66