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529 FXUS65 KBOU 060016 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 516 PM MST Thu Mar 5 2026 .KEY MESSAGES... - Snow develops tonight in the high country, Friday morning for the lower elevations. Difficult travel expected for mountains, foothills and Palmer Divide with moderate to heavy snow at times. - Lighter accumulations (mostly 1-2", locally 3") anticipated for the urban corridor and plains Friday. Morning commuters should prepare for slick conditions. - Snow tapers off Friday afternoon/evening north to south. Milder and drier weather expected Saturday into early next week. && .DISCUSSION /Through Thursday/... Issued at 1218 PM MST Thu Mar 5 2026 The next 24 hours will bring a taste of typical Colorado spring weather as we transition from today`s warm temperatures and clear skies to cold and snow on Friday. On satellite, we`re beginning to see some striations of mid-level cumulus develop in the high country, with more expansive moisture and showers forming across the Western Slope. This will progress east through the afternoon, with snow showers initiating in our mountains early this evening and increasing through the overnight period when they`ll expand into our foothills. By this evening, a cold front will drop into the plains, with temperatures steadily cooling to near freezing by sunrise, and bringing a gradual moistening of the lower levels. A few snow or rain/snow showers will be possible overnight for the urban corridor (mainly north of Denver) but almost all of the snow will hold off until after daybreak Friday. Lee cyclogenesis will intensity Friday, although there`s been a slight weakening trend in the intensity of the surface low in most model guidance over the past 12-24 hrs. The overall picture remains largely the same as yesterday, with robust north and north-northwest flow confining any upslope component to the Palmer Divide and southern foothills. Nonetheless, strong QG ascent and frontogenesis will ensure everyone participates in the party to some degree. Friday morning will see the bulk of the impacts as steady snow develops across the I-25 corridor and becomes heavier in our mountains and foothills. Localized snowfall rates of 1-2"/hr can be expected under the heaviest showers/bands, most likely along and south of the I-70 mountain/foothills corridor, and across the Palmer Divide, but will otherwise be lower. Some minor snow accumulations do look to impact the Friday morning commute around the Denver metro area, but ambient and road temperatures will likely be rather marginal with wet bulb values hovering in the 31-34F range much of the time. Suspect that roadway accumulations for most of the urban locations will be largely contingent on snowfall intensity. As such, opting to refrain from any winter headlines for the metro itself as true accumulations are currently forecast to remain in the 1-3" range, however commuters should prepare for slick conditions in the morning regardless. A surge of stronger north winds will develop in the afternoon as the surface cyclone becomes better defined over NW Kansas, and this will steadily usher in drier low-level air, tapering off snowfall from north to south. Total snowfall of 6-14" is expected in our mountains and foothills (heaviest south of Rocky Mountain NP), with 3-8" for the Palmer Divide, and generally 1-3" elsewhere. Northern portions of the I-25 corridor will be less favored given the downslope flow off the Cheyenne Ridge, and will thus be closer to the lower end of that range. Similarly, accumulations should be comparatively limited in the plains where temperatures will hover in the mid to even upper 30`s, despite a likely band of greater precipitation extending northeast from the Palmer Divide into Morgan/Washington/Logan Counties. Milder and drier weather returns for Saturday, and the warming trend will continue through Monday as we transition to zonal flow aloft and a mostly subsident pattern. The high country will see a slight day-to-day increase in westerly winds as the jet slowly inches southward into early next week. More distinct troughing then looks to develop over the northern plains for the middle of the work week, which should further boost winds in our mountains and foothills. Unfortunately, ensemble guidance continues to trend away from widespread precipitation potential for midweek. It`s still non-zero, but a significant system that would serve to make a dent in our expanding drought doesn`t appear to be in the books. && .AVIATION /00Z TAFS through 00Z Saturday/... Issued at 501 PM MST Thu Mar 5 2026 VFR conditions through tonight. A denver cyclone has situated itself over the Denver metro which has allowed easterly winds at DEN and BJC and southerly winds at APA. Expect winds to gradually turn northeast for DEN and BJC as the cyclone exits the region. Surface observations show a cold front located in northern Weld county. The front is progged to reach DEN and BJC by 03Z and APA by 04Z. Northerly winds gusting up to 35 kts is expected. Recent hi-res guidance indicates a couple of hours of weaker northeasterly winds before a resurgence, particularly between 06-09Z. However, due to low confidence of that actually materializing, have left it out of the TAF for now. Expect northerly winds to continue through the TAF period. Ceilings will lower behind the front tonight, dropping to 5000-8000 ft by 06Z/07Z, and 3000-5000 ft between 07Z and 12Z. Snowfall is expected after that, with ceilings as low as 500 ft at times. There is a chance for snowbanding Friday morning, resulting in visibilities dropping down to 1/2 mile if that occurs. Snow will gradually end by Friday evening, with visibilities reaching above 6 miles by 00Z/01Z. However, expect low ceilings of 1000-2000 ft to linger through Friday night. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from midnight tonight to midnight MST Friday night for COZ030-032-035>037. Winter Weather Advisory from midnight tonight to 8 PM MST Friday for COZ031. Winter Storm Warning from midnight tonight to midnight MST Friday night for COZ033-034. Red Flag Warning until 6 PM MST this evening for COZ241. Winter Weather Advisory from 6 AM Friday to midnight MST Friday night for COZ041. && $$ DISCUSSION...BRQ AVIATION...MAI