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200 FXUS65 KBOU 030658 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1158 PM MST Mon Mar 2 2026 .KEY MESSAGES... - Mountain snow and low-elevation rain likely through Tuesday evening, with highest rainfall amounts north of I-76. - Potential for colder storm system with more widespread snow Thursday night through Friday, although uncertainty in amounts remains. && .DISCUSSION /Through Monday/... Issued at 1152 PM MST Mon Mar 2 2026 Current water vapor imagery shows an upper level shortwave trough over southwestern Wyoming/northeastern Utah. This weak system will trek into Colorado by Tuesday morning, with moisture advecting into the region. Scattered mountain snow showers will continue overnight tonight and throughout the day Tuesday. Given how warm we have been lately, snow levels will be around 8000-8500 ft overnight, before dipping down to 7000-7500 ft with the arrival of cooler air from the shortwave. The overall snowfall forecast for the mountains were not changed significantly from the previous forecast, with highest snow accumulations limited to elevations above 10,000 ft. The biggest change to the forecast is the precipitation amounts for the northern plains. Recent guidance now favors the 500-mb vorticity max right over the plains Tuesday, with good mid-level forcing throughout the day (mid-level lapse rates will be around 7-8 dg/km). The surface lee cyclone continues to trend farther south than previous runs, which will allow moisture to be pulled further south into the northern plains. Hi-res guidance now favors some areas receiving upwards of 0.50" of QPF by throughout Tuesday, with a few solutions indicating 1.00". Due to this, have increased amounts for areas north of I-76. Unfortunately, Denver area will not see the bulk of this precipitation, as guidance still favors ~0.10" of QPF. Expect rain showers across the foothills and plains throughout the day Tuesday before gradually ending northwest to southeast overnight. Upper level ridging will return to the state Wednesday and Thursday, with increased southwest flow aloft on Thursday ahead of an incoming trough. Temperatures will rebound to the 60s by Wednesday and possibly lower 70s by Thursday. ECMWF ensemble has consistently been warmer than the GEFS, with 36 out of 50 members showing max temperatures between 70-72 (compared to the GEFS, where all 30 members show max temperatures between 62-68 degrees). With these warm temperatures and dry conditions, elevated to critical fire weather conditions are possible on Thursday, particularly the Palmer Divide and eastern plains, where lee cyclogenesis could promote gusty winds. Guidance continues to be in good agreement of a shortwave trough breaking into two pieces of energies on Friday, with the weaker one ejecting into the northern Great Plains, and the other one trekking towards southern California and becoming a closed low. Cold air will advect into the region, with 700-mb temperatures dipping to -6 to -9 dg C. Moisture will begin to stream into the region by late Thursday night into the mountains, and Friday morning across the plains. At the surface, a lee cyclone will strengthen slightly and trek northwest, with a cold front pushing through the plains. Precipitation is possible across the forecast area, as GEFS and ECWMF ensembles have consistently shown measurable QPF with the latest few runs (and even snow!). However, how much moisture is still the question, as it will depend on the exact track of the ejecting trough. As of now, the ECMWF has a slightly southerly track than the GFS, which brings more moisture and colder air into the region. By the weekend, we will likely have weak flow aloft as Colorado looks to be in between the two systems. Dry conditions and warmer temperatures should prevail for the mountains and plains. && .AVIATION /00Z TAFS through 00Z Wednesday/... Issued at 548 PM MST Mon Mar 2 2026 VFR conditions are expected through at least tomorrow morning. A front will pass through the area starting around 05-07z bringing N winds with it, especially at BJC and DEN. Ceilings will start to lower at this time with a stratus deck moving into place. At APA, we expect the winds to be from SW to NW throughout the night tonight. A stronger push of N winds will occur with the frontal passage around 15-16z Tuesday affecting all 3 sites. Gusts could be as high as 25 to 30 kts as the front passes. There is a low possibility that rain could occur tomorrow morning at BJC. There is high confidence (50-80%) that rain will accompany the front during the late morning and afternoon hours tomorrow. PROB30 groups were added to account for uncertainty in the timing of the onset of the rain. Ceilings could be as low as between 500 and 1000 feet AGL, especially in the afternoon tomorrow with any showers that pass through according to BUFKIT soundings and cross sections. We accounted for this with TEMPO groups at all 3 sites for lower ceilings and lower visibility (as low as 4 SM at BJC and 5 SM at DEN and APA). There is agreement across several hi-res models that the ceilings will gradually rise Tuesday evening as the rain clears. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...MAI AVIATION...MV