National Weather Service Forecast Discussion |
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760 FXUS65 KBOU 231212 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 532 AM MDT Sat May 23 2026 .KEY MESSAGES... - Warmer and drier this weekend, with only isolated showers and storms possible each afternoon/early evening. - Remaining mild next week, but scattered afternoon and evening showers and storms expected most days. && .DISCUSSION /Through Friday/... Issued at 1212 AM MDT Sat May 23 2026 A shortwave trough is tracking across central andeastern Colorado at this time. Showers over the eastern plains will diminish as they track eastward, ending before sunrise. Subsidence and drier air will prevail behind the exiting shortwave trough. Temperatures warm up today with highs reaching the 70s across northeast Colorado. A few high-based showers are possible with outflow winds reaching 30 mph. The best chance for isolated high- based showers will be over the higher terrain. Upper level ridging begins to develop late Saturday and by Sunday an upper level ridge will prevail over the Central Rockies. Temperatures will continue to warm for Sunday with highs in the lower to mid 80s across northeast Colorado. Mostly dry conditions will continue with only a few high-based showers/thunderstorms possible. A weak upper level trough approaching from the Desert Southwest will push the ridge axis east of Colorado on Monday. However, the ridge will still influence the weather with warm temperatures continuing. An uptick in moisture is expected to increase shower and thunderstorm coverage Monday afternoon and evening. A large upper level low over the Pacific Northwest will track south-southeast and eject the weak trough out of the Desert Southwest. The trough then moves across the Central Rockies on Tuesday. This will lead to slightly cooler temperatures and a better chance for showers and thunderstorms. For Wednesday through Friday, the large upper level low stalls over the western states as ridging blocks its eastward advancement. South to southwest flow aloft is expected with a southeast low level flow. This is expected to increase moisture and lead to cooler temperatures. Daily afternoon and evening showers and thunderstorms are expected under this pattern. && .AVIATION /12Z TAFS through 12Z Sunday/... Issued at 532 AM MDT Sat May 23 2026 VFR will persist through the period.South to southwest will continue into this morning, 14-15Z and then become light as they transition to a northwest direction this afternoon. There is some uncertainty whether winds will be north to northwest or just light and variable this afternoon. However, wind speeds are expected to be light (less than 15 knots) even if there is a prominent direction. High-based cumulus clouds will develop this afternoon with bases at 8,000-10,000 feet. Virga and outflow winds will be possible, but they currently look limited, so decided against including a tempo or PROB30. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...12 AVIATION...12