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955 FXUS65 KBOU 020556 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1156 PM MDT Wed Apr 1 2026 .KEY MESSAGES... - Areas of fog northern Denver suburbs to portions of the northeast plains early this morning. - Quick but brief warm up today, with breezy southwest winds and locally critical fire weather conditions developing in the afternoon. - Turning blustery and colder tonight through Friday. Another round of snow in the mountains, this one with more impacts due to colder temperatures. Plains still look mostly dry with only isolated light showers possible. - Dry with a gradual warming trend this weekend through early next week. && .DISCUSSION /Through Wednesday/... Issued at 1155 PM MDT Wed Apr 1 2026 One system is moving out with showers ending and clearing skies across the plains. The exception is some fog developing over the northern sections of Denver which should spread/migrate slowly northward into the early morning hours Thursday as light southerly drainage winds spread down the South Platte River Valley. That fog will burn off by mid morning, allowing more sunshine and warming temperatures. Highs will quickly rebound from the cooler readings of the last couple days as sunshine, downslope, and warm advection under a flat ridge all join forces. It will become breezy in most areas, but likely not until afternoon, and potentially not until very late afternoon or early evening in a few spots north of Denver which will hold inversions the longest. Highs should still be able to reach the lower 70s over most of the plains. See Fire Weather Section for more info regarding winds and humidity and locally critical fire weather conditions. For tonight and Friday, the next upper level disturbance will move into the region. This is a more compact and colder upper low than the last, but the track will be too far north (through Wyoming) to bring us much chance of precipitation east of the mountains as significant downslope develops. The mountain areas, however, will see a quick blast of healthy snow starting this evening but diminishing about as fast overnight as more stable air arrives along with drying aloft. Thus, snow totals will be marginal for any highlights, but we do expect some travel impacts as temperatures will be considerably colder with this storm system. Some impacts may linger into Friday as models suggest a bit of wrap around moisture impacting the mountains mainly north of I-70, but additional accumulations should be light as moisture looks relatively limited. A strong cold front will blast across the plains this evening with a period of gusty winds and colder temperatures. It`s not impossible we see a brief light shower behind the front given the jet location and frontogenesis, but overall moisture looks meager and downslope dominates. By Friday, the flow turns more west/northwest and strong subsidence develops as shown in quite impressive QG fields. 700 mb winds increase to 35-40 kts and given the subsidence we will see healthy mixing and momentum transfer. Thus, most plains locations including the I-25 Corridor should see 40-45 mph wind gusts through the day. However, with the impressive subsidence would not be surprised to see stronger gusts especially in the wind prone areas near the foothills and near the Wyoming border where gusts to 55 mph seem reasonable - close to High Wind Criteria. We`ll continue to monitor with later updates. After that system, our weather settles down as the flow aloft gradually relaxes. With flat ridging, we expect gradual warming through early next week. There is good ensemble agreement with temperatures through Sunday, and then some uncertainty Monday - Wednesday with potential for backdoor cold fronts sloshing across the plains. That said, the overall trend will be for warmer and mostly dry weather. We`re eyeing another potential storm system for late next week...we`ll need to keep em coming to aid our current drought situation. && .AVIATION /06Z TAFS through 06Z Friday/... Issued at 1142 PM MDT Wed Apr 1 2026 Rain showers have moved off to the east and clouds are quickly dissipating with skies becoming mostly clear. These clear skies combined with light winds and recent rainfall will lead to fog. At DEN, fog has quickly formed over the past hour with visibility falling under a mile. Expect fog to set in through most of the overnight hours at DEN and BJC with visibility falling to a quarter mile or less. APA should see enough south wind to keep fog from forming, but BR with a slight visibility restriction will be possible. Southerly winds creep up from the south and will provide enough drier air to scour the fog out at DEN, mostly likely between 12-14Z. Once the fog dissipates, VFR to prevail Thursday under mostly clear skies. Southwest winds will continue through this afternoon. Winds increase after 20Z with gusts to around 35 knots. Southwest winds then decrease after 00-01Z, but a cold front will bring a wind shift to the north to northwest and increase winds 03-05Z. && .FIRE WEATHER... Issued at 1155 PM MDT Wed Apr 1 2026 Thursday will see critical wind gusts to 30-35 mph and humidity down to near 15% over the Palmer Divide area into east central Colorado. However, we did have about a tenth of an inch of rain from Elbert County through northern Lincoln County so that should help today`s fire concerns a little. Thus, we`ve opted to upgrade only southern Lincoln County where little if any precipitation occurred. For Friday, strong and gusty west-northwest winds can be expected. Humidity readings will be reaching near critical thresholds despite the cooler temperatures. We may issue Fire Weather Watches as humidity values drop to 15-20% (above criteria), but winds will be stronger and gust to 40-45 mph in many locations of the plains and I-25 Corridor. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from noon to 8 PM MDT Thursday for COZ247. && $$ DISCUSSION...20 AVIATION...12 FIRE WEATHER...20