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881 FXUS65 KBOU 290826 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 226 AM MDT Sat Aug 29 2026 .KEY MESSAGES... - Warm again today, with increased chances of showers and thunderstorms this afternoon and evening. - Active monsoon pattern continues Sunday and Monday. - Warm and dry pattern returns for most of next week. && .DISCUSSION /Through Friday/... Issued at 212 AM MDT Sat Aug 29 2026 Water vapor satellite imagery suggests that the plume of deeper monsoon moisture is slowly approaching our forecast area tonight, with broad southwesterly flow aloft to the north of a slowly weakening ridge. Today will see more scattered showers and thunderstorms, with a bit more coverage compared to yesterday. A slight increase in boundary layer moisture along with slightly cooler mid-level temperatures will lead to a modest increase in instability for the afternoon, and convective initiation will likely be aided by a sagging mid-level front this afternoon and evening. Both the HREF and REFS suggest widely scattered thunderstorms developing by the early afternoon, and at least a few showers and storms are likely to linger through most of the evening and early overnight hours (especially closer to the front). The plume of monsoon moisture isn`t expected to move much on Sunday. The lack of synoptic forcing will likely limit storm coverage across the plains, but scattered showers and storms are forecast across the high country during the afternoon hours. A more pronounced shortwave is expected to move through the region on Monday or Monday night, leading to an increase in storm coverage across most of the state. Recent models are a little too slow with this wave for most of our forecast area to benefit from the increased synoptic scale ascent, with better chances for precipitation off to the south and west of our CWA. Still, widely scattered showers/storms are forecast again, perhaps lingering through most of the overnight hours across the plains where the environment would support elevated convection. Moisture quickly diminishes by Tuesday as the ridge continues to weaken and push off to the east. The latter half of the week looks rather quiet with the ridge restrengthening over the southeastern CONUS, before slowly drifting back towards the region as we approach next weekend. High temperatures should approach 90F across the plains most days, with a gradual warming trend likely by this time next week. && .AVIATION /06Z TAFS through 06Z Sunday/... Issued at 1137 PM MDT Fri Aug 28 2026 VFR conditions are expected to continue through the TAF period. A weak boundary did briefly cause some disruption to the drainage flow at DEN but should this should quickly resume by 07z. A bit more confidence that winds remain WSW/W during the late morning and early afternoon hours on Saturday, before coming a bit more messy as convection develops near or after 20z. Variable and gusty outflow winds will again be the main concern for most of the afternoon and evening hours. Some SHRA may linger into the early overnight hours Saturday night, and a weak frontal push may briefly turn winds more northerly before an eventual return to drainage flow overnight. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Hiris AVIATION...Hiris