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234 FXUS65 KBOU 161122 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 522 AM MDT Mon Mar 16 2026 .KEY MESSAGES... - Strong winds across portions of the mountains, mainly along and south of I-70 and along Highway 285 in Park county, through early afternoon. - Mountain snow showers, producing a few inches of accumulation for the higher elevations, will continue through Tuesday. - Steady, continued warming will begin today and continue through next weekend. Hot/dry/breezy weather will sustain prolonged high fire danger for the northern plains each day. - All-time hottest March temperatures appear increasingly likely (>80% chance) for many locations Friday and/or Saturday, including for both the mountains and lower elevations. && .UPDATE... Issued at 302 AM MDT Mon Mar 16 2026 Am concerned about strong winds this morning thru early aftn mainly along and south of I-70 in the mountains and across HWY 285 in Park county. Cross-sections show a decent mtn wave with cross-barrier flow up to 60 kts. With potential impacts along HWY 285 have decided to issue a High Wind Warning. Meanwhile, satellite analysis shows an area of snow cover along HWY 285 from Como to Kenosha Pass which could have very poor visibility in blowing snow at times. && .DISCUSSION /Through Sunday/... Issued at 1039 PM MDT Sun Mar 15 2026 A few light snow showers are hanging on mainly west of I-25 along the base of the foothills owing to weak upslope flow through 3km MSL per the Table Mountain profiler. With the meridional jet departing to our east, lingering lift will dissipate over the next couple of hours and bring an end to the snow across the lower elevations. It will be a cold night with lows in the teens and single digits for most locations. We`ll warm up moderately Monday as heights rise and subsidence returns to the lee of the Front Range, though did lower highs a couple of degrees for the lower elevations given signs in some high- res guidance of continued weak easterly surface flow through the day. Most areas are thus favored to remain in the 40`s, with lingering cloud cover also muting the potential to hit 50F. In our mountains, the approach of a second north/south oriented jet max and another surge of mid-level moisture should promote redevelopment of orographic snow showers during the day, and these will continue intermittently through Tuesday. Have increased PoPs a reasonable amount over our higher mountains in particular given the quite unanimous signal for additional light accumulations for the higher peaks over the next 24-48 hours. The jet will lift to our northeast by Tuesday as a well-defined ridge of high pressure emerges over SoCal. More pronounced warming is expected, with high temperatures set to rebound into the 70`s for the lower elevations. This ridge will see a gradual eastward migration through the week, as well as amplification, leading to a steady warming trend each day through at least Saturday. Unfortunately, with the ridge centered to our southwest much of the week, northeast Colorado will remain under an enhanced northwest flow pattern. With efficient mixing each day, this favors development of breezy afternoon winds, especially for our northern plains that are more exposed to this prevailing wind direction. As such, areas from the Cheyenne Ridge east towards Nebraska and Kansas will likely see a prolonged period of critical fire weather conditions from Tuesday through Saturday, exacerbated by building heat and very low humidity. This is ratified by the elevated probabilities of exceeding 95th percentile HDWI Tuesday through Saturday. As far as temperatures are concerned, little has changed given the rather consistent signal observed in ensemble guidance. We are confident in progressively more anomalous heat each day through at least Friday, with that trend more than likely extending into Saturday as well (>85% chance). The ECMWF`s EFI exceeds the 95th percentile each day from Thursday through Saturday, indicating just how unusual such a prolonged stretch of warm temperatures would be for our area. There are some factors, such as cloud cover, that could still influence our chances at setting all-time March records for some locations such as Denver. However, there are quite a few locations with extensive historical records for which those records appear quite easily attainable: Breckenridge (61F), Fort Collins (81F) and Akron (85F) are some examples of cities with a greater than an 80% chance of experiencing their hottest March day Friday and/or Saturday. The probability of that occurring in Denver is moderately lower, but still significant (~60%). && .AVIATION /12Z TAFS through 12Z Tuesday/... Issued at 515 AM MDT Mon Mar 16 2026 Ceilings overnight have scattered out at all of the sites with only some mid and high level cloud cover currently. Based on current trends, may not see ceilings down to 7000 ft this morning with just a middle to higher deck thru the aftn. Winds were light S/SE and will trend to light eaterly at DIA by 17z with winds becoming north at APA and NW at BJC. For the aftn winds at DIA will become more NE with N/NW winds at APA and BJC. May see some gusts up to 25 mph at BJC thru the aftn. For tonight, will continue to see some mid and higher level cloud cover. Winds will become light NE at all three airports by 01z and then go to drainage in the 04Z-06z time period. && .BOU WATCHES/WARNINGS/ADVISORIES... High Wind Warning until 2 PM MDT this afternoon for COZ034. && $$ UPDATE...RPK DISCUSSION...BRQ AVIATION...RPK