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790 FXUS65 KBOU 301125 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 525 AM MDT Mon Mar 30 2026 .KEY MESSAGES... - Well above normal temperatures continue today. - Critical fire weather conditions for the mountain valleys, Front Range Foothills, and adjacent plains today. - Cooler by Tuesday with snow in the mountains and a chance of precipitation over the plains. Chances for precipitation increase for Wednesday. - Potential for another system to impact the region by the end of the week. && .DISCUSSION /Through Sunday/... Issued at 1239 AM MDT Mon Mar 30 2026 Temperatures didn`t quite make it to the forecasted high at KDEN Sunday (80F), but we did end up tying the previous record high of 79 degrees last set in 1967. Nonetheless, it was another abnormally warm day across the forecast area, and Monday is still expected to be about the same. We do expect westerly winds aloft to increase through the morning, and with a surface trough keeping westerly downslope winds in place, this will translate to critical fire weather conditions developing for portions of the foothills and adjacent plains as well as North and Middle Park (more in fire discussion). Increasing mid-level moisture will support low chances (10-15%) for high-based virga showers once again. No precipitation is expected, but gusty outflows up to 35 mph will be possible with any passing virga showers. A shortwave is expected to traverse the northern Rockies through the afternoon, with an associated cold front sliding south across Colorado late Monday night/early Tuesday morning. Latest trends show precipitation over the lower elevations holding off until a little later than previously advertised, with northerly winds keeping things dry south of the Cheyenne Ridge due to downsloping, and lacking low-level moisture in place until later in the day. Therefore, should just see some gusty winds (35-45 mph) colder temperatures, and increasing cloud cover with the initial frontal push. Locations along the Wyoming border south to about Fort Collins may end up with some light precip due to modest frontogenesis expected Tuesday morning. Moisture is expected to deepen throughout the day on Tuesday as Pacific moisture continues to increase within the southwesterly flow aloft. PVA will also increase ahead of another approaching shortwave that will increase lift across the region. There are still some uncertainties with the position of a 500 mb jet. The ECMWF would put us in the right exit region which would be unfavorable for precip on the plains, whereas the GFS would have us in closer proximity to its left exit region that would support better chances for our lower elevations. Despite some minor differences between guidance, the current forecast calls for up to .4" of QPF for the lower elevations and between .5" to 1.2" of QPF to our mountains through Thursday morning. While temperatures will mostly be too warm for snow across the lower elevations, the NBM continues to show a 30-40% chance for up to .1" of snow for our northeast corner. Snow levels will be low enough to support snowfall down to roughly 8,500 feet, but the majority of snow will fall above 10,000. Snow totals have come down slightly with this forecast, but the northern mountains are still expected to see about six to ten inches of snow accumulations, while the central mountains can expect between five to eight inches. A more active pattern will continue into the weekend, though there remains much variability between guidance still. A more potent upper-level trough is expected to drop out of the Pacific Northwest on Thursday, potentially impacting Colorado by Friday and into the weekend. Variability in it`s north vs southward extent could mean large differences for what we see across the CWA. We will have to watch and see how things trend through the week, but we are looking at potential for at least some additional light snow for the mountains, and more rain for the lower elevations. && .AVIATION /12Z TAFS through 12Z Tuesday/... Issued at 525 AM MDT Mon Mar 30 2026 VFR to prevail through the TAF period. South to southwest winds will continue this morning and then turn westerly 18-20Z as slightly stronger west winds aloft mix down. Gust of 15 to 25 knots will be possible, with the stronger winds expected at BJC. Like the past two afternoons, wind direction may become muddled at times this afternoon. After 03-05Z, winds are expected to return to a south- southwest drainage direction. A cold front will bring a gusty wind shift to the north-northeast 11-12Z Tuesday morning. && .FIRE WEATHER... Issued at 1239 AM MDT Mon Mar 30 2026 Another day of record-breaking temperatures is expected on Monday. With increasing winds and relative humidities expected to range from 8% to 16% across the majority of the forecast area, a Red Flag Warning is in place from 11 AM to 8 PM for the Front Range Foothills and adjacent plains. Additionally, we have added North and Middle Park into the warning and removed metro Denver as wind speeds have trended downwards for the metro area with this forecast package, and RH has lowered for the mountain valleys. However, with RH as low as 8% expected across the metro area, there will be elevated fire weather conditions in place through the afternoon across all of the lower elevations. A cold front is expected early Tuesday that will bring cooler temperatures to the forecast area, snowfall to the mountains, and widespread precipitation chances to the plains. This will keep critical fire weather conditions at bay for at least a few days. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from 11 AM this morning to 8 PM MDT this evening for COZ211-213-215-216-238-239-242-243. && $$ DISCUSSION...9 AVIATION...Meier FIRE WEATHER...9