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085 FXUS65 KBOU 100557 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1057 PM MST Mon Nov 9 2026 .KEY MESSAGES... - Above normal temperatures and dry conditions will likely prevail through Friday. - Increasing chances for light mountain rain/snow showers by this weekend. && .DISCUSSION /Through Monday/... Issued at 1050 PM MST Mon Nov 9 2026 Our weather pattern this week will be dominated by a persistent upper level ridge over the western United States. This will keep our forecast area dry with above normal temperatures through Friday. By this weekend, a weak system could bring light precipitation (30-40% chance as of now) to the high country and cooler temperatures to the region. Current water vapor satellite imagery shows a weak upper level shortwave over the far Pacific Northwest. This will trek across the northern United States and into the northern Great Plains Tuesday and into Wednesday. While this system will be too far away from Colorado for any precipitation chances, there will be increased cloud cover over our region on Tuesday, which should keep temperatures over the Denver area a few degrees cooler than Monday. However, still expect maximum temperatures to be in the mid-to-high 60s across the plains. A "cool" front (if you can even call it that) associated with the system will bring breezy winds to the northern and eastern plains, with gusts up to 20-30 mph possible in the afternoon. Due to this, elevated fire weather conditions will be possible. However, relative humidity values should stay above critical thresholds, especially with the expected cloud cover. We will be a bit cooler on Wednesday, with highs in the low-to-mid 60s. But, this will be short-lived as the axis of the upper level ridge should shift over wester Colorado on Thursday and Friday. Temperatures in the mid-to-high 60s will return, with a few ensemble solutions showing low 70s. Ensemble guidance does favor a weak system moving through the region over the weekend. This will give us our first chance in a while for mountain rain/snow showers. Accumulations look light at this point, given the lack of decent moisture and strong forcing. For the plains, precipitation chances do not look as favorable over the weekend. However, there could be an isolated rain shower or two. We should begin cooling down towards the beginning of next week, with seasonal temperatures returning and possibly a more active pattern. Stay tuned... && .AVIATION /06Z TAFS through 06Z Wednesday/... Issued at 1048 PM MST Mon Nov 9 2026 VFR will persist through the TAF period. Fairly normal drainage winds from the SW at KDEN will hold through about 15Z, and then become VRB under 6 kts through about 18Z. While we do see a push of stronger northwest winds coming off the Cheyenne Ridge after 18Z, most models suggest development of an anticyclone which means a more NE-E wind component for the TAF sites after 18Z, and even SE by 00-01Z. There`s a 20-30% chance we could still go more northerly in the 18Z-00Z period. There is also uncertainty for wind direction tomorrow evening - depending on the strength of a subsequent surge moving across the plains. That could briefly shift winds more N-NE (30-40% chance). For now, we`ll keep winds more SE til eventually more typical drainage winds from the S-SW develop, and those would likely be delayed til after 06Z due to the above mentioned surge. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...MAI AVIATION...20