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309 FXUS65 KBOU 172039 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 239 PM MDT Sat Oct 17 2026 .KEY MESSAGES... - Mainly dry and mild for the season through the middle of next week. - Next storm system will arrive late next week with an increasing chance of showers and mountain snow. && .DISCUSSION /Through Saturday/... Issued at 233 PM MDT Sat Oct 17 2026 Not a cloud in the sky today across our area with soundings and current observations showing 40-50 degree dewpoint depressions and a dry vertical profile. Winds will remain light, with the exception of the easternmost Colorado plains, where southerly winds at 10-15 mph with sporadic gusts up to 25 mph will be possible. As such, elevated to locally critical fire weather conditions may occur over portions of Lincoln and Washington counties this afternoon although these conditions should be short-lived. High temperatures this afternoon are expected to be in the mid 70s for the low elevations, while the mountains experience a wider range of temperatures in the 50s and 60s. Cloud cover from a decaying disturbance will drift over the region tomorrow leading to temperatures a few degrees cooler than today, though still in the low 70s for the plains and Denver metro. A return to southwest flow aloft and a weak shortwave will bring a slight chance (15-25% PoPs) for some rain and snow showers over the high terrain Monday, although no snow accumulation is expected and rainfall amounts will reach a trace at most. An upper level trough will start to deepen off the Pacific Northwest coast late Monday night. This upper level trough will slide south and become a strong cutoff low as it approaches the California coast and begins to move east on Wednesday. Southwest flow aloft will intensify across the Four Corners region ahead of this cutoff low on Wednesday afternoon, bringing increasing moisture and precipitation chances for the high country late Wednesday into Thursday. Upper level flow will turn more southerly on Thursday, and this is when the bulk of the Pacific moisture plume will arrive. However, as it stand now, our area will likely be under a downsloping regime with south-southwesterly flow favoring orographic lift over southwestern Colorado and the San Juan Mountains primarily. This will be a system to watch as the week progresses given that slight changes in the track of this cutoff low could bring the potential for heavy rain closer to our area. Regarding snow chances with this system, the airmass appears to be too warm to support snow levels lower than 10,000-11,000ft until the next cold front arrives on Saturday, likely after the moisture has moved off to the east. && .AVIATION /18Z TAFS through 18Z Sunday/... Issued at 1105 AM MDT Sat Oct 17 2026 VFR conditions expected through the TAF period with virtually no clouds. Winds are starting to become VRB before settling into a east/southeast direction this afternoon. Winds return to drainage tonight. There is a low (~20% chance) that KBJC sees some stronger downslope winds, up to 15 kts, early Sunday morning. Expect a similar pattern tomorrow- winds briefly VRB and then east/southeast. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...AA AVIATION...MV