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071 FXUS65 KBOU 301948 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 148 PM MDT Sun Aug 30 2026 .KEY MESSAGES... - Scattered showers and storms capable of producing strong to severe wind gusts are expected to continue through the evening. - Better precipitation chances on Monday, with another round of afternoon/evening showers and storms, a few may become severe. - Warmer and drier conditions expected from Tuesday onward. && .DISCUSSION /Through Sunday/... Issued at 124 PM MDT Sun Aug 30 2026 Current radar shows storms are making their way off the northern Front Range early this afternoon, with another round moving across the Continental Divide. The primary hazard with today`s showers and storms will, once again, be strong outflow winds. So far, storms have been producing a few tenths of rainfall and wind gusts between 40 to 50 mph. Storms have been moving between 30-40 kts, which will help keep flash flooding concerns limited, but if we do see any back- building, there is enough moisture in place to see some heavy downpours, mainly across the higher elevations. While today`s instability is expected to be slightly increased over Saturday, it remains fairly weak, with only a few hundred to roughly 500 J/kg of MLCAPE observed on the SPC mesoanalysis. CAMs continue to be in decent agreement about high-based storms/showers continuing their trek eastward across the plains through the afternoon and evening. These will be capable of producing strong outflow winds, with at least a few severe wind gusts possible. Current temperature readings show roughly a ten degree difference from this time yesterday, with today`s afternoon highs forecast to run a few degrees cooler than yesterday. Southwesterly flow aloft will continue to usher monsoonal moisture into Colorado on Monday. Given the increased moisture, proximity to the right entrance of a 500 mb jet, and the aid of lift from an approaching shortwave sometime in the afternoon/evening, this will be our best chance for precipitation across the forecast area with this wave of monsoonal moisture. CAMs continue to show a cluster of storms move through the Four Corners Monday morning, pushing northeast across Colorado through the day. We could see a few stronger to severe storms in the afternoon, with the CAMs honing in on the better instability being along and east of the Palmer Divide (as high as ~1200 J/kg of MLCAPE). Given the better moisture, we will have a better chance for some localized heavier rainfall amounts, but with the mean flow aloft roughly moving 35-40 kts, this should help limit flash flood potential. Additionally, with DCAPE ranging from 1200-1500 J/kg across the plains, generally east of the urban corridor, the primary threat will be with gusty outflows once again, but with increasing 0-6 km bulk shear, we may see some marginally severe hail with some of the stronger storms. Depending on the timing of the shortwave, we could see showers/storms linger late into the night. Near normal temperatures are expected across the forecast area. Southwesterly flow aloft will remain in place through the week as the upper-level ridge persists over the eastern US. Monsoonal moisture is expected to continue flowing into the region, but amounts are expected to diminish for a few days midweek, as the higher amounts should stay to our southeast. Things in the Pacific look to become active over this period, from a parade of storms moving towards Hawaii, to a fairly strong closed low dropping south along the West Coast. Depending on how these features interact, we could see some more active weather return by late in the week, but for now, the forecast calls for slightly less convection each afternoon after Monday, with near normal temperatures on Tuesday, gradually warming through the end of the work-week. && .AVIATION /18Z TAFS through 18Z Monday/... Issued at 1145 AM MDT Sun Aug 30 2026 Radar as of 1745z shows a broken line of showers and thunderstorms moving through Grand, Jackson, and western Larimer counties. Based on the latest radar trends and CAMs, have kept a TEMPO and VCSH starting at 20z (adjusted KBJC to start at 19z) for the possibility of high-based showers and thunderstorms for much of the afternoon. These could bring gusty outflow winds in excess of 35 kts, rain, and briefly lowering ceilings. There is a ~30-40% chance that showers and thunderstorms linger through about 4z this evening. Behind the convection, winds should turn to drainage rather quickly... as early as 4z. Winds should turn clockwise to north-northeast to northeast by early tomorrow afternoon. Tomorrow will be another day with a TEMPO and VCSH starting at 20z for similar threats- gusty outflow winds in excess of 35 kts, rain, and briefly lowering ceilings. Ceilings could briefly drop to around 7000 feet AGL given more mid-level moisture is expected to be present. A PRO30 or TEMPO will likely be needed past 0z Tuesday in the next update. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...9 AVIATION...MV