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385 FXUS65 KBOU 261104 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 404 AM MST Fri Dec 26 2025 .KEY MESSAGES... - Warm and dry for the plains today with elevated to near- critical fire weather conditions over the southern foothills, South Park, southern Denver metro, and Palmer Divide. - The mountains will see snow beginning tonight and 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. && .UPDATE... Issued at 333 AM MST Fri Dec 26 2025 Continued warm temperatures across the plains today. Elevated to near critical fire weather conditions are possible across the southern foothills, South Park, southern Denver metro and the Palmer Divide. Have continued the Winter Storm Watch for zone 31 for late tonight through late Saturday night, but a prolonged period of snow accompanied by gusty winds, especially early in the event, is likely. The heaviest snow is espected for the Park and Gore Ranges, but snow will spread across most of the Colorado mountains and onto the plains Saturday evening through Sunday morning. The snow develops behind a cold front that moves into the plains Saturday evening. Behind the front, temperatures will be much colder given the mild temperatures we`ve had throughout the week. && .DISCUSSION /ThroughThursday/... Issued at 333 AM MST Fri Dec 26 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 /12Z TAFS through 12Z Saturday/... VFR through the TAF period. Some mid and high level cloudiness is expected throughout the day. Winds should remain fairly steady and southerly through at least 20Z today. Some uncertainty in windspeeds later this afternoon at KBJC and KAPA, as gusty southwesterly winds develop in the southern foothills and southern metro area. Could see some higher gusts, around 25kts, make it into the KBJC and KAPA sites. Winds should eventually transition back to normal south/southwest around 10 kts by 02Z Saturday. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Storm Watch from late tonight through late Saturday night for COZ031. && $$ UPDATE...Stark DISCUSSION...Danielson AVIATION...Stark