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764 FXUS65 KBOU 291134 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 534 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 /12Z TAFS through 12Z Sunday/... Issued at 531 AM MDT Sat Aug 29 2026 VFR through the TAF period. Drainage winds this morning will slowly turn more to the west, which should then prevail through most of the day today. Convection still looks on track to develop around 19-21z this afternoon. Inverted-V soundings will again favor gusty outflow winds, though there is enough instability today for some TSRA potential as well. Guidance still lingers some showers/storms into evening hours, and are in better agreement on bringing a frontal push (or perhaps just an organized outflow) from the north by about 03-06z. Drainage winds are still expected to develop later Saturday night, and should slowly turn clockwise through Sunday morning. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Hiris AVIATION...Hiris