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745 FXUS65 KBOU 171939 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1239 PM MST Tue Feb 17 2026 .KEY MESSAGES... - Very windy with critical to extremely critical fire weather conditions today for all of the eastern Colorado plains. - Periods of snow and blowing snow through Thursday will likely lead to continued travel impacts through most of the week. - Additional fire weather concerns for elevated to critical fire weather conditions Wednesday. - The plains may see their first chance of measurable snow on Friday night. && .DISCUSSION /Through Tuesday/... Issued at 1135 AM MST Tue Feb 17 2026 A strong cold front moved through Colorado this morning briefly producing heavy snow in the mountains and rain along and west of the I-25 corridor. It is nice to receive rainfall across lower elevations on a Red Flag Warning day but it will have little impact on the critical fire weather conditions. We are already seeing critical fire weather conditions on the plains and the fire weather concerns are discussed further in the Fire Weather section below. Water vapor imagery shows strong subsidence and a dry intrusion moving across the I-25 corridor. As it moves across our forecast area, dew points are decreasing rapidly and winds are increasing. Wind gusts will reach up to 65 mph on the plains and a High Wind Warning remains in effect. The winds will decrease around sunset so the warning goes through 5 pm. Despite the subsidence aloft, there is enough moisture and favorable orographic flow for scattered snow showers to form in the mountains throughout the day today. Steep lapse rates mean snow showers will be briefly moderate to heavy in intensity. The western slopes of the mountains will see another 1-4" of snow today. Water vapor also shows another area of higher moisture in Utah that will move across Colorado tonight. More widespread but less intense snow will spread across the mountains tonight with another few inches possible. A shortwave trough will move from California to Colorado on Wednesday. This will provide QG ascent across our forecast area. The mountains will continue to see healthy coverage of snow. Across the plains, it will be another mild and windy day with southwest winds. The will be critical fire weather concerns across the east-central plains that is discussed in the fire weather section below. There will be steep lapse rates that develop across the plains during the afternoon on Wednesday and some rain showers will form with light precipitation reaching the surface. This same shortwave trough will slow its eastward progress and become stronger Wednesday night into Thursday. 12Z guidance showed two potential impacts for our forecast area from this trough. The first is the potential for strong winds over the Front Range foothills and adjacent plains early Thursday morning. Some gusts could reach 60 mph in the typical windy spots in the foothills. No highlights were issued at this time although if the mountain wave setup intensifies, a High Wind Warning may be considered. The other potential impact is moderate snow across the far northeast corner of Colorado. 12Z guidance was more confident that a TROWAL will move over far northeast Colorado with strong 700 mb frontogenesis. This would allow for a 12 hour period where areas like Julesburg could receive up to 6" of snow although that is the high end amount. PoPs were increased over the northeast plains to account for this chance of snow. The exact impacts and snow amounts will be hard to forecast until Wednesday night and the northeast corner of Colorado should monitor the forecast. Yet another shortwave trough will move over Colorado late Friday and into Friday night. Recent model guidance has increased the chance for precipitation to fall across the plains especially on Friday night. This could end up being the first measurable snow of the month for Denver. The mountains will see another round of light to moderate snow from this system. Ridging will build in over Colorado Sunday into early next week. This will lead to warmer and drier conditions. && .AVIATION /18Z TAFS through 18Z Wednesday/... Issued at 1052 AM MST Tue Feb 17 2026 West/southwest winds have decreased for DEN and APA to less than 30 kts. Expect stronger west winds to return by 20Z (BJC will likely remain gusty) with gusts up to 40 kts possible. Winds will begin to weaken after sunset, although gusty westerly winds up to 25 kts is still possible through the evening for all TAF sites. In addition, it is worth to note that a few hi-res guidance indicate a brief northwest winds at DEN and BJC before turning to drainage by 03/04Z. Stronger than normal drainage winds for tonight, up to 15 kts at times. By mid-morning tomorrow, winds are expected to pick up again, with gusts up to 30 kts possible through the afternoon. && .FIRE WEATHER... Issued at 1135 AM MST Tue Feb 17 2026 The Red Flag Warning for today is already verifying across the I-25 corridor and eastern plains. The strong subsident flow has allowed very dry air to be mixed down to the surface. Centennial Airport has a dew point of -4 F which is resulting in a relative humidity of 9%. Other areas will have relative humidity drop below 10% across the plains especially along and south of I-70. Wind gusts have reached over 60 mph across the plains and those strong winds will continue through the afternoon. Critical to extremely critical fire weather conditions will continue through around 6-7pm this evening. No changes were made to the Red Flag Warning. Wednesday will have gusty winds potentially up to 50 mph over Elbert and Lincoln Counties. In addition, there will be relative humidity that will drop to around 15%. Given the very dry fuels the decision was made to issue a Red Flag Warning for fire weather zones 246 and 247 in Elbert and Lincoln Counties during the day tomorrow. If there is confidence in higher winds than currently forecast in Washington County and surrounding areas, then the Red Flag Warning may need to be extended northward by a later shift. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 11 PM MST Wednesday for COZ030- 032>034. Winter Storm Warning until 5 AM MST Thursday for COZ031. Red Flag Warning until 7 PM MST this evening for COZ238>251. High Wind Warning until 5 PM MST this afternoon for COZ038- 042>051. Red Flag Warning from 11 AM to 7 PM MST Wednesday for COZ246-247. && $$ DISCUSSION...Danielson AVIATION...MAI FIRE WEATHER...Danielson