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339 FXUS65 KBOU 252136 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 236 PM MST Thu Dec 25 2025 .KEY MESSAGES... - Warm and dry for the plains Friday with elevated to near- critical fire weather conditions over the southern foothills, Denver metro, and Palmer Divide. - The mountains will see snow beginning Friday night lasting through Sunday morning. The heaviest snow amounts will be in the Park and Gore Ranges with a Winter Storm Watch issued there. - Lower elevations will see light snow Saturday night into Sunday morning. Much colder temperatures expected to accompany the snow. && .DISCUSSION /Through Thursday/... Issued at 145 PM MST Thu Dec 25 2025 A weak ridge aloft within the southwesterly flow will move over Colorado on Friday. This will bring in drier air with slightly cooler high temperatures. Some light snow showers are possible in the Park Range mountains but the rest of the mountains and plains should remain dry during the day. The main concern on Friday will be elevated to near-critical fire weather conditions. This is discussed further in the fire weather section below. A combination of a trough over the Southwest US and a trough approaching from the Pacific Northwest will move towards Colorado late Friday night. This will bring a wave of Pacific moisture to the mountains of Colorado. Moderate to briefly heavy snow will arrive after midnight in the Park and Gore Ranges. Snow will then spread across most of the Colorado mountains late Friday night and through the day on Saturday. Strong mid level frontogenesis will move across northern Colorado Saturday evening through early Sunday morning. Across the plains, there will be a cold front at the surface will will push through around the same time dropping temperatures quickly. Behind the front, northeast winds will develop which will create upslope flow. All of these factors will come together to create a couple bands of snow that will spread across the area oriented from southwest to northeast. Ensemble guidance has been consistent with regard to QPF across the plains with roughly 0.15-0.20" across the northern Denver metro and around 0.25" on the south side of the metro. With the light upslope flow, 2-5" of snow is forecast for the western I-25 corridor and Palmer Divide while 1-4" of snow is forecast on the east side of the I-25 corridor. Across the eastern plains, 0-2" of snow is forecast. There will be moderate snow amounts in the Front Range mountains and foothills. Some of the higher mountains and ski areas may see close to a foot of snow. With the help from the moderate to heavy snow late on Friday night, the Park and Gore Ranges will see the highest snow amounts. Therefore, a Winter Storm Watch was issued for forecast zone 31. Cold temperatures are expected Sunday night with the fresh snow and clear skies. Single digit lows are forecast across the plains with the usual cold spots of Greeley and Limon potentially getting close to 0 F. Next work week will see dry conditions with temperatures increasing. Highs will be above normal by Wednesday. && .AVIATION /18Z TAFS through 18Z Friday/... Issued at 1205 PM MST Thu Dec 25 2025 Models have west to northwesterly winds at DIA this afternoon then they transisition to normal drainage patterns by late evening. More normal diurnal wind patterns are expected on Friday. There will be no ceiling issues. && .FIRE WEATHER... Issued at 145 PM MST Thu Dec 25 2025 Drier air will move into the forecast area on Friday with relative humidity dropping to 10% across the southern foothills, Denver metro, and Palmer Divide. Gusty winds are expected over the higher terrain with gusts up to 55 mph in the Front Range mountains. In the foothills and adjacent plains, gusts could reach 35 mph. This will lead to elevated to near-critical fire weather conditions across the southern foothills, Denver metro, and Palmer Divide. However, the highest wind gusts and lowest relative humidity are not expected to overlap. Therefore, no fire weather highlights were issued. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Storm Watch from late Friday night through late Saturday night for COZ031. && $$ DISCUSSION...Danielson AVIATION...66 FIRE WEATHER...Danielson