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126 FXUS65 KBOU 011923 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1223 PM MST Sun Mar 1 2026 .KEY MESSAGES... - Warm and dry Monday, with near-critical fire weather conditions across the Palmer Divide. - Mountain snow and low-elevation rain likely (>80% chance) Monday night into Tuesday evening, favoring areas north of I-70. - Potential for colder storm system with widespread snow Thursday night through Friday, although uncertainty in amounts remains elevated. && .DISCUSSION /Through Sunday/... Issued at 1212 PM MST Sun Mar 1 2026 A cooler air mass is in place today following last night`s backdoor front in the plains, and weak shortwave which produced 1-3" of snow in our mountains. With exception of the higher mountains above the inversion, our 24-hr temperature trends range from around 5 degrees cooler in the mountain valleys to up to 25 degrees cooler than this time yesterday for our northeast plains. These more seasonal conditions will be interrupted again Monday, as warmer southwesterly subsident flow returns and pushes highs into the lower 70`s across portions of the plains and urban corridor, potentially even approaching daily records in a few locations. Some of the southwest winds aloft will surface across our mountains and Palmer Divide, producing near-critical fire weather conditions for the latter where gusts 25-30 mph may briefly develop. The passage of a positively-tilted shortwave over the region on Tuesday will bring some snow showers to our mountains beginning Monday night, with rain showers spreading into the lower elevations during the day Tuesday. Trends indicate a slight northward shift in the moisture trajectory in the past 24 hrs, increasing confidence in most of the precipitation remaining north of the I-70 corridor. Temperatures will be too warm to support snow accumulation for the lower elevations, though a wintry mix isn`t out of the question later in the day for the northeast plains and perhaps the Palmer Divide. Precipitation amounts look to range between 0.10-0.30" for the plains, with our northern mountains receiving 2-6" of snow, although even a small continued northerly shift in the storm track would reduce these further. Dry conditions and a rebound in temperatures (back into the 60`s for the lower elevations) can be expected for Wednesday into Thursday ahead of the arrival of our next system which, wouldn`t you know it, is a messy one (quite typical for this of the year). The synoptic interactions become complex late in the week, with an initial shortwave favored to traverse the Central Rockies as a secondary low attempts to simultaneously detach from its parent trough and eject southwestward towards AZ/SoCal. It`s a complicated pattern that lends itself to considerable variance in weather impacts for Colorado depending on subtle nuances with respective tracks and development of lee cyclogenesis. The mountains are less dependent on these differences and thus confidence in winter weather impacts is slightly higher (compared to our lower elevations) for the Thursday night through Friday timeframe, but snowfall amounts remain a large question mark regardless. Meanwhile, plains and urban corridor impacts are less defined. That being said, cold air aloft will be more expansive with this tandem of upper-level lows, and thus would support snow and not rain if lower-elevation precip does materialize. Some degree of upslope flow could also be in the mix depending on the scenario, which would boost impacts for portions of the Front Range, but it`s too early to discern such details. Drier and milder conditions are then favored to return for the weekend. && .AVIATION /18Z TAFS through 18Z Monday/... Issued at 1037 AM MST Sun Mar 1 2026 VFR conditions will persist through the TAF period. Fairly light (