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336 FXUS65 KBOU 151501 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 901 AM MDT Sun Mar 15 2026 .KEY MESSAGES... - Much colder temperatures today with light snow ending over the plains this morning. Gusty winds with areas of blowing dust and elevated fire weather concerns will impact the plains. - In the mountains, snow will taper off this morning but gusty winds will produce some blowing snow over the higher passes. - Save for light mountain snow showers Monday, a steady warming and drying trend will take hold through the week. Fire weather concerns may return to the lower elevations as early as Tuesday. - We`re continuing to monitor the potential for record-breaking March heat by late week. && .UPDATE... Issued at 849 AM MDT Sun Mar 15 2026 The intensity and coverage of snow across the southern Denver metro and Palmer Divide has been surprising this morning. A snow band has been over Centennial Airport area for the last 2 hours and cameras show runways are snow-covered with plenty of snow accumulation in the grass. Across the Palmer Divide, snowfall totals of 3-5" have been common with snow continuing. The cameras show hazardous travel conditions on I-25 near Monument Hill with completely snow-covered roads. Since snow will continue through the morning hours, a Winter Weather Advisory was issued for the Palmer Divide zone. There was consideration for issuing a Winter Weather Advisory for the southern foothills and eastern Jefferson County but road conditions are somewhat better in those areas so no advisory was issued. The Winter Weather Advisory for the I-70 corridor mountains was extended until noon to account for the current snowfall and hazardous travel conditions. UPDATE Issued at 301 AM MDT Sun Mar 15 2026 Strong cold front has moved across all of the plains early this morning with a band of heavier snow across the Palmer Divide out towards the Limon area. Overall should see a gradually end to snow from north to south by sunrise as much drier air moves in from the north. Mtn areas will still see some light snow thru the day with gusty winds producing some blowing snow over the higher passes. Very windy conditions will continue over the plains this morning, however, latest data suggest the strongest winds will occur thru noon and then decrease this aftn. && .DISCUSSION /Through Saturday/... Issued at 928 PM MDT Sat Mar 14 2026 Our extended period of Chinook winds is coming to an end as a strong cold front, located near Chugwater WY as of 0930 PM MDT, rips south overnight. The front looks to reach the Fort Collins area near 1130 PM, and Denver closer to 1 AM MDT. A sharp temperature drop of around 15 degrees in 30 minutes can be expected, with temperatures falling to around freezing shortly after the frontal passage, and with gusts 35-55 mph impacting all of the lower elevations. Behind it, convective snow showers will produce a short window of snow for most areas along the urban corridor, although with how quickly the bulk of the moisture will move through, accumulations will be quite limited. For the most part, the I-25 corridor stands to see a dusting to an inch, although localized accumulations of 1-3" remain possible generally from Denver south and mainly into the Palmer Divide. More considerable travel impacts are anticipated in our mountains between midnight and sunrise, when a period of locally intense snow squalls will lead to brief 2-3"/hr snowfall rates coinciding with strong winds exceeding 60 mph at times, bringing potential for whiteout conditions for most of the major mountain travel corridors. Snow will have largely tapered off by sunrise Sunday, however occasional light snow may linger through Sunday evening for most areas, with little to no additional accumulation. Sunday will be a cold and blustery day regionwide, with highs only slightly rising above freezing for the warmest locations in the plains and urban corridor. Post-frontal winds from the north will remain steady and rather strong, particularly east of the I-25 corridor, gusting 50-55 mph, and potentially close to 70 mph at times in the vicinity of the I-70 plains corridor. A window of elevated fire weather conditions is likely for the plains in the afternoon as humidity lowers to near 25%, with the locations of concern delineated by those areas that receive little/no snow early this morning (more likely for the rural plains). Sunday night will be the coldest of the week, as lows drop into the teens to low 20`s for the plains and urban corridor respectively, and into the single digits and teens for most mountain communities. Monday will bring warmer temperatures to the region with approximately 15-20 degrees of warming. A few snow showers may continue in the mountains thanks to a secondary surge of mid-level moisture embedded in the northwesterly flow aloft. Only light accumulations are expected for the higher elevations, with limited to no travel impacts. Unfortunately, fire weather concerns look to resurface as early as Tuesday as low-level winds and well-mixed conditions return, under continued warming. Some question as to just how dry we get, and the spatial extent of such conditions, but our northern tier of counties appears most susceptible to locally critical fire. As we`ve been advertising for some time now, highly anomalous upper-level ridging will become increasingly dominant across the southwestern US and Intermountain West late week and into the weekend, leading to temperatures climbing to 20-30 degrees above normal as we enter the weekend. We`re still a ways out to be able to iron out the finer details (exact highs, likelihood of reaching/exceeding monthly records, and exact timing of the peak of the heat), but a prolonged stretch of highs at or above 80F does appear increasingly likely for this time period across much of our lower elevations. && .AVIATION /12Z TAFS through 12Z Monday/... Issued at 522 AM MDT Sun Mar 15 2026 Light snow had ended at BJC and DIA but continues at APA. APA should see light snow end between 13z and 14z. Ceilings were improving at BJC and DIA and should rise above MVFR at APA by 14z. Winds have decreased early this morning but expect them to increase by 13z or 14z with gusts from 40 to 45 mph at times thru 18z. This aftn wind gusts should be more in the 30 to 35 mph range and then decrease to 25 mph or so by 22z. Wind directions will stay mainly north but will become NE after 22z with lighter winds by 01Z. Overnight winds will become light drainage by 05z. Will continue to see ceilings later this morning thru the early evening hours between 6000 and 7000 ft. These ceilings will scatter out by 05z. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until noon MDT today for COZ034-041. High Wind Warning until 3 PM MDT this afternoon for COZ040>051. && $$ UPDATE...Danielson DISCUSSION...BRQ AVIATION...RPK