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585 FXUS65 KBOU 232020 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 120 PM MST Mon Feb 23 2026 .KEY MESSAGES... - Another big warm-up for the upcoming work week. - Strong winds expected along the east slopes of the Front Range Mountains and foothills on Tuesday. - Snow chances return to the mountains Tuesday night. - Elevated to critical fire weather conditions possible across the plains through the week (Friday). && .DISCUSSION /Through Monday/... Issued at 120 PM MST Mon Feb 23 2026 Strong upper level high will remain centered over the southwest part of the country and Baja Mexico through at least Saturday. Colorado will be on the periphery of the ridge. We`ll see the warm and mostly dry conditions under this pattern. However, strong northwest flow aloft will be over or just north of Colorado bringing breezy to windy conditions at times, especially to northern Colorado. For tonight and Tuesday, flow aloft increases as the jet sinks south and nears Colorado. Winds increase along the east slopes of the Front Range mountains and foothills tonight, likely becoming strong Tuesday morning. Ridgetop winds increase to 50 to 60 knots by Tuesday morning. Models in good agreement with some mountain wave amplification of theses winds down to about 7000 feet MSL with gusts to 80 mph possible. This is not a classic mountain wave set up for the lower foothills and adjacent plains. There is little to no ridge top stable layer and strong mid to upper level winds, which tends to sheer the mountain wave. For the adjacent plains, channels/fingers of gusty winds to 45 mph will be possible Tuesday. This combined with warm temperatures and relative humidities in the teens will lead to elevated to critical fire weather conditions. (See Fire Weather Discussion below). The jet continues to slowly sink southward Tuesday night and Wednesday. This will help to increase Pacific moisture and provide lift for snow over the mountains. Mountain snow is expected to increase over the mountains Wednesday as a shortwave trough embedded in the northwest flow nears Colorado. Snowfall amounts Tuesday night through Wednesday night looks to be 6 to 12 inches for most of the mountains (Advisories issued) and up to 16 inches for the Park and Gore ranges (Warning issued). For the lower elevations Wednesday, warm and windy conditions are expected with wind gusts up to 55 mph. Moisture slowly increases ahead of the shortwave trough Wednesday, helping to keep relative humidities above 20 percent. May be enough lift and moisture for a few weak showers over the eastern plains. A weak cold front (more so a wind shift) pushes south through eastern Colorado during the early evening hours, possibly bringing a few showers to the Palmer Divide, southern foothills, and Denver metro area. Any precipitation is expected to be light. The front and eventual subsidence behind the shortwave is expected to produce windy conditions through at least Wednesday evening. For Thursday and Friday, strong northwest flow aloft continues with the jet stream overhead. Expect warm and dry conditions to persist under this pattern. Windy conditions and elevated to critical fire weather conditions will continue to be the main weather concern. On Saturday, the jet reorganizes over the Northern Plains, bringing less wind and decreasing the fire weather threat. Models showing a cold front pushing south through the area sometime Saturday. Could be morning, afternoon, or evening. This will lead to cooler temperatures possibly for Saturday but more likely for Sunday. The upper level ridge finally begins to shift eastward Sunday and Monday. Another jet streak will be possible during this time frame, possibly bring snow to the mountains with a chance for light rain over the plains. Temperatures decrease a little, but remain above normal for this time of year. && .AVIATION /18Z TAFS through 18Z Tuesday/... Issued at 1108 AM MST Mon Feb 23 2026 VFR conditions expected throughout the TAF period. The main forecast difficulty will be determining the strength and frequency of west or west-northwest winds at all terminals this afternoon and Tuesday afternoon. There are mountain wave clouds that have developed over the western I-25 corridor this morning and should limit mixing. Some west-northwest winds will gust up to 12 knots at times at DEN and up to 25 knots at BJC but due to limited mixing, winds will more frequently be around 7-9 knots. Therefore, winds in the TAF were decreased slightly at both airports. This evening, southeast winds will develop before drainage takes over around 05Z. The pressure gradient will be stronger during the day on Tuesday so there is a higher likelihood of gusty westerly winds at all terminals in the afternoon. Gusts could reach 30 knots at BJC and up to 24 knots at DEN. However, the winds will more frequently be around 10-14 knots at both airports so that was included in the DEN TAF. && .FIRE WEATHER... Issued at 120 PM MST Mon Feb 23 2026 Red Flag Warnings were issued for the foothills and adjacent plains for Tuesday. Winds for the foothills down to about 7000 feet are expected to be strong with gusts to 80 mph. Even though relative humidities don`t fall into the lower to mid teens here, upper teens and lower 20s will result in critical fire weather conditions. On the plains, channels of stronger winds to 45 mph are expected from Fort Collins and southward. Some locations may not see the stronger winds (possibly light east winds). However, given some areas may see wind gusts well above the 25 mph threshold with relative humidities down to 10 percent, opted to hoist a widespread Red Flag Warning. On Wednesday, widespread windy conditions are expected with gusts to 55 mph. An approaching storm system will increase low level moisture possibly leading to a few weak showers over the plains. With relative humidities expected to stay above 20 percent decided not to issue a Red Flag Warning. The warm, dry, and possibly windy pattern continues for Thursday and Friday. Location of the stronger winds is still uncertain. Models generally favor northern Colorado and northward. A slight shift north would take the stronger winds out of Colorado, while a southward shift would bring widespread windy conditions both days. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning from 8 PM Tuesday to midnight MST Wednesday night for COZ031. High Wind Warning from 8 AM to 6 PM MST Tuesday for COZ033>035. Winter Weather Advisory from 8 PM Tuesday to midnight MST Wednesday night for COZ033-034. Red Flag Warning from 10 AM to 5 PM MST Tuesday for COZ215-216- 238>240-242-243. && $$ DISCUSSION...12 AVIATION...Danielson FIRE WEATHER...12