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756 FXUS65 KBOU 200551 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1151 PM MDT Sat Sep 19 2026 .KEY MESSAGES... - A few morning showers/storms across our northern tier of counties this morning, with potential for a strong to marginally severe storm or two over the eastern plains later in the day. Otherwise dry for most of the area. - Expect cooler conditions through Monday, with more limited shower and thunderstorm coverage. - Gradual warming returns Tuesday onwards, with generally isolated precipitation chances each day. && .DISCUSSION /Through Saturday/... Issued at 1113 PM MDT Sat Sep 19 2026 Showers continue to trek across the mountains and northern tier of our forecast area, associated with the approaching upper-level trough. As its axis shifts east, we may see a few embedded thunderstorms in the north/northeast plains after sunrise. Notably cooler temperatures can be expected across the lower elevations, where highs may struggle to break the 70 degree mark in the coolest areas (mainly the Palmer Divide and far NE plains). Most areas will see reduced CAPE relative to previous days, limiting afternoon shower/t-storm coverage considerably. Have further reduced PoPs across our mountains and urban corridor for this period, maintaining only a very slight chance (15-20%) of precipitation. The axis of better instability (and shear) will be confined to our eastern plains, where a few stronger to marginally severe storms may develop. Transient ridging pushes in for Monday into Tuesday leading to a gradual rebound in temperatures and comparatively drier conditions. An isolated shower or storm could make an appearance mainly south of I-70 Monday, and increasing southwest flow ahead of a developing closed low over Nevada on Tuesday should promote a few isolated afternoon showers in the high country. That low is then slated to lift NE, merging with the broader flow pattern over the Northern Rockies Wednesday, promoting a slight increase in showers and thunderstorms predominantly to our mountains, with more isolated coverage elsewhere. Behind this, ensemble means favor steadily building high pressure over Colorado, supporting additional modest warming and potential for temperatures to return to the 80`s for some of the lower elevations for the second half of the week. Precipitation chances will be fairly slim, but enough moisture could remain trapped beneath the ridge to allow for isolated afternoon showers most days. && .AVIATION /06Z TAFS through 06Z Monday/... Issued at 1113 PM MDT Sat Sep 19 2026 VFR conditions are expected to prevail for all terminals through the TAF period. With current drainage winds now favored to hold through at least 13-14Z, and the transition to NE winds seemingly delayed until closer to 15Z, the potential for fog and low stratus this morning appears much reduced. Have thus taken any mention of this out of the TAFs. NE flow is expected to hold at the terminals most of the day, with a gradual shift to a more easterly direction through the afternoon. Convective potential will be limited, with only a 15-20% chance of a shower or thunderstorm after 21Z. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...BRQ AVIATION...BRQ