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759 FXUS65 KBOU 221832 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1232 PM 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 /18Z TAFS through 18Z Saturday/... Issued at 1231 PM MDT Fri May 22 2026 Current winds are generally light and variable, with some N-NE winds starting to arrive at KDEN. Winds will continue to turn clockwise this afternoon, with light easterlies by 00Z. However, strong southerly winds will take over by around 02Z due to an outflow originating over the Palmer Divide, near KAPA. KAPA will see the best chance for an isolated thunderstorm early this evening between 00-03Z, in addition to a 30% chance for showers through 06Z. KBJC and KDEN will have a lower probability of seeing showers over the terminals, but we opted to introduce a PROB30 for KDEN between 02-04Z given that current observations show a moister environment than previously depicted by high-res model guidance. Winds late tonight will remain mostly S-SSW before a shift to more westerly winds tomorrow morning. High-based showers will begin to develop over the foothills around 19-21Z Saturday afternoon, bringing the potential for variable gusty outflows and microbursts. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...12 AVIATION...AA