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473 FXUS65 KBOU 140006 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 606 PM MDT Sat Sep 13 2025 .KEY MESSAGES... - Scattered/numerous showers and thunderstorms this evening, with an isolated threat of severe storms across the northeast plains. - Scattered showers and a slight chance for thunderstorms, mainly north Sunday morning. - Unsettled, uncertain pattern for most of next week. && .DISCUSSION /Through Saturday/... Issued at 228 PM MDT Sat Sep 13 2025 Water vapor satellite imagery showing a strong shortwave trough over Utah with scattered/numerous showers and thunderstorms ahead of it over western Colorado. Over northeast Colorado, SBCAPE has reached 300-800 J/kg (more than yesterday). Lift from the trough combined with the instability in place is expected to bring scattered/numerous showers and thunderstorms to northeast Colorado later this afternoon and evening. Can`t rule out an isolated severe thunderstorm or two, but most/all storms are expected to be sub- severe. Best chance for a severe storm will be over the northeast plains. The trough lifts north of Colorado tonight and will be over western Nebraska Sunday morning. Will keep a chance for showers in the forecast through the night as the trough tracks across Colorado. The best chance for additional showers will be wrap around showers on the backside of the low towards sunrise Sunday morning. Showers slowly come to an end from west to east Sunday morning and may linger into the afternoon over the northeast corner. Highs Sunday are expected to reach the lower to mid 70s across northeast Colorado. The upper level trough to our northeast lifts northward and merges with the longwave trough over western Canada and the Northern Rockies. Colorado will see a somewhat dry westerly flow Monday around the base of the trough. This will bring warmer temperatures with highs in the lower to mid 80s across northeast Colorado. A shortwave trough embedded in the longwave trough to the north pushes southward bringing a cold front and chance for showers Tuesday. Troughiness remains over the area into Wednesday with cooler temperatures and continued chance for showers. For Thursday through Saturday, models are starting to converge on a solution. They are showing ridging developing west of the region Thursday. The ridge intensifies into Friday and Saturday over the Central Rockies. This is expected to produce dry conditions with temperature at or above normal. Chances for precipitation are low, but we could see a few showers/thunderstorms if enough moisture filters in under the ridge. && .AVIATION /00Z TAFS through 00Z Monday/... Issued at 556 PM MDT Sat Sep 13 2025 Another round of showers could move through all TAF sites the next couple of hours, so have kept the PROB30. However, the atmosphere near APA is still unstable, so have changed the TAF to include thunder. For the rest of the night, a W/NW flow will dominate all sites, with drainage winds possible just before sunrise. Ceilings will fall between 5000-8000 ft overnight. By 13Z Sunday, another round of showers is possible, along with the chance (