National Weather Service Forecast Discussion |
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323 FXUS65 KBOU 111136 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 436 AM MST Wed Nov 11 2026 .KEY MESSAGES... - Above normal temperatures and dry conditions will prevail through Friday. - Increasing chances for light mountain rain/snow and rain showers for portions of the plains by this weekend. && .DISCUSSION /Through Tuesday/... Issued at 1040 PM MST Tue Nov 10 2026 Slightly cooler temperatures are expected on Wednesday due to weak cold air advection aloft as eastern Colorado will be situated on the eastern edge of the well-advertized upper level ridge. However, it will still be warm, with highs in the low-to-mid 60s across the plains. Similar to the past few days, quiet weather will prevail with mostly clear skies. On Thursday and Friday, the axis of the upper level ridge will shift east, allowing slightly warmer temperatures to return to the region. However, ensemble guidance has trended cooler these past few runs, so we don`t have as good of a chance to hit 70 F in the plains. This is reflected in DESI probabilities dropping to 20-25% chance of temperatures meeting or exceeding 70 F. Regardless, we will stay dry across the region. Guidance continues to hone in on a system this weekend bringing mountain rain/snow showers and possibly precipitation to portions of the plains. However, there are still many uncertainties with the track and evolution of this system that will impact how much mountain snow we will get and how widespread rain across the plains could be. Recent runs of the GEFS and ECMWF ensemble have trended towards a stronger shortwave trekking across Colorado, with some solutions resolving a closed low near southeast Colorado. However, models diverge with the track of the low pressure after that, with some tracks being too far south or east for our region to see the bulk of the expected precipitation. As of now, ensemble guidance is in agreement of light snow accumulations for the high country (mainly above 8000-8500 ft) Saturday through Sunday, and increasing chances for rain showers for our eastern plains on Sunday. It is still too soon to tell if the rest of the plains, including the Denver metro would see measurable precipitation from this system. Fall-like weather will likely return by Saturday or Sunday, with temperatures nearing seasonal normals for the first time in a while. Ensemble guidance is in good agreement of cooler temperatures sticking around through the rest of the forecast period. There is a good signal that active weather will return by mid-week next week with multiple systems providing precipitation chances for the forecast area. && .AVIATION /12Z TAFS through 12Z Thursday/... Issued at 436 AM MST Wed Nov 11 2026 VFR conditions will persist through the TAF period. S winds at KDEN and KAPA are expected to hold til 16Z-17Z. As typical, a period of light and VRB winds is then expected before turning more E-NE by 20-21Z, although a 40% chance they stay VRB. Expect a gradual return to SE-S 02Z-06Z which will then hold til at least 15Z Thursday. Speeds will remain under 10 kts. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...MAI AVIATION...20