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373 FXUS65 KBOU 020508 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1008 PM MST Thu Jan 1 2026 .KEY MESSAGES... - Light mountain snow through Friday, with locally moderate accumulations in the Park Range and parts of the northern mountains. - No meaningful precipitation expected for lower elevations through at least Wednesday, with continued warm/dry conditions. - Breezier winds forecast Friday in the high country and plains; More widespread Sunday, with increased fire danger for lower elevations and foothills. - Signs of transition to wetter and colder pattern around Thursday of next week, but with plenty of uncertainty. && .DISCUSSION /Through Thursday/... Issued at 141 PM MST Thu Jan 1 2026 Elevated moisture has begun to intrude into the high country, with some spillover into the foothills and urban corridor. Low- levels have moistened enough to support development of light snow showers in the higher elevations, and as expected also some isolated virga and a few rain drops along and west of I-25. Not much change is anticipated into the evening, with continued light snow in the mountains which won`t amount to much accumulation. Snow will increase in our northern mountains tonight and Friday with the arrival of more robust flow aloft, leading to 3-9" of accumulation for most of the Park Range, with a few localized totals potentially surpassing 10" for the highest elevations. Forcing will remain too weak for comparable impacts along the Continental Divide and particularly southward into the I-70 mountain corridor, with the latter expected to receive around 1-3" for most locations above ~9,500 ft. Breezier conditions will materialize over the higher terrain through Friday too, extending into our northeast plains in the afternoon with a weak and dry frontal passage. Temperatures should be approximately 2-5 degrees cooler Friday given the cold air advection and cloud cover. High pressure returns this weekend, pushing low elevation highs above 60F again Saturday, and peaking Sunday when we`ll be close to daily records. Dry conditions will be favored, although a few very light showers can`t be ruled out in our high country Sunday as a subtle shortwave approaches. Behind said shortwave, enhanced westerly flow associated with a jet max will increase cross- barrier winds to around 50 kts by sunrise Sunday. As of yet there`s no real indication of either a critical or stable layer in model guidance, but cross-sections do favor limited or even reverse shear profiles above 600mb. With QG subsidence in place, at lease some eastward spread of breezier winds into the lower foothills and adjacent lower elevations appears likely (~70% chance), with peak gust potential mostly in the 40-60 mph range outside of the most wind-prone mountain/foothills locations, which could see a few gusts near 70 mph. The subsident flow regime and warm temperatures will allow for relatively dry conditions from the foothills eastward, so there`s potential for a brief window of near-critical to locally critical fire weather conditions if there`s sufficient alignment between ingredients. The strengthening southwest flow aloft will provide for increased precipitation chances in our mountains Monday and Tuesday, with just an outside chance (~20%) for some light showers surviving into the lower elevations. Temperatures should see a steady decline beginning Monday and continuing through midweek. Ensembles over the past 24-48 hours have appeared slightly more excited about the prospect of winter weather returning to the lower elevations as early as Thursday, January 8th, along with a transition to a colder pattern thereafter. Is it one of the more robust signals we`ve seen for low-elevation snow since early December? Yes. Have we seen such signals fade over the course of a week only to end up dry? Also yes. In summary: ensemble guidance suggests that you should keep coming back to read our discussions and see how things evolve. In the meantime, enjoy the mild temperatures! && .AVIATION /06Z TAFS through 06Z Saturday/... Issued at 1005 PM MST Thu Jan 1 2026 Winds will go drainage in the next few hours and stay that way thru Fri morning. Winds by early aftn will become N to NW and continue thru early Fri evening. VFR conditions will continue with only some mid and higher level clouds moving across thru the period. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 5 PM MST Friday for COZ031. Winter Weather Advisory until 5 PM MST Friday for COZ033. && $$ DISCUSSION...BRQ AVIATION...RPK