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249 FXUS65 KBOU 220701 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 101 AM MDT Fri May 22 2026 .KEY MESSAGES... - Scattered showers and thunderstorms late this afternoon and evening, mainly south of I-70. Remaining cool. - Warmer and drier this weekend, with isolated showers possible Saturday afternoon. - Remaining mild next week but with a return of potential afternoon showers and thunderstorms. && .DISCUSSION /Through Thursday/... Issued at 101 AM MDT Fri May 22 2026 Water vapor satellite imagery shows an upper level trough over Montana and Wyoming with lift extending south into northern Colorado, bringing additional showers and thunderstorms at this time. The showers come to end by sunrise as subsidence and drier air move into the area. It will be cooler today, behind last night`s cold front with highs in the 60s across northeast Colorado. A shortwave trough is lined up to track east across the area this evening. Best lift (and chance for showers/storms) is expected over central and southern Colorado with this wave. The first showers and storms are expected late this afternoon with the best chance for showers and storms this evening over the Palmer Divide. This activity ends overnight and by Saturday morning, dry conditions are expected. Ridging begins to develop over the Central Rockies Saturday and by Sunday, it will be centered over Colorado. This will bring a warming and drying trend to the area. There may be just enough moisture under the ridge for isolated weak showers and thunderstorms. The ridge slides east of the region Monday as an upper level low moves onto the southern California coast. Flow aloft turns southerly, keeping warm temperatures in place. Moisture may start to increase Monday, but it is more likely Tuesday. Since this is several days out, the pattern details are unclear. However, if models continue on their current path, a more active pattern is expected to begin Tuesday and should continue into at least Thursday. We`ll be looking at near normal to slightly above normal temperatures.Daily afternoon/evening showers and thunderstorms are expected. && .AVIATION /06Z TAFS through 06Z Saturday/... Issued at 101 AM MDT Fri May 22 2026 An upper level trough is bringing a second round of showers to northern Colorado with ceilings falling to 4000 to 7000 feet. Most (perhaps all) of the showers and lower clouds will stay to the north and northwest of DEN. The threat for showers and these lower clouds ends 09-10Z, after which drier air moves in and clouds are expected to scatter. North to northeast winds are expected to continue this morning and this afternoon. Winds will shift to southeast to south in the 00-02Z window. The next round of showers develops late Friday afternoon and evening, after 22-23Z and lingers through about 06Z Saturday. Best chance for thunderstorms will be south of Denver, over the Palmer Divide. There`s about a 30 percent chance for thunderstorms at APA and less at DEN. Gusty southerly outflow winds are likely though sometime after 00Z Saturday. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...12 AVIATION...12