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734 FXUS65 KBOU 280541 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1141 PM MDT Thu Aug 27 2026 .KEY MESSAGES... - Isolated/scattered high based showers/storms Friday with gusty winds. - Temperatures return to the 90s Friday and Saturday across the plains. - Thunderstorm coverage increases for late Saturday through Monday. && .DISCUSSION /Through Thursday/... Issued at 302 PM MDT Thu Aug 27 2026 The upper level high and ridge axis shifts over Colorado today, bringing warmer temperatures and drier air. Precipitable water values fall to near normal (0.6-0.9") across the area. MLCAPE will be around 500 j/kg, so we should see some shower/thunderstorm activity. However, mid level warming is expected to limit development this afternoon and evening. With DCAPE values of 1000-1500 j/kg, gusty outflow winds will be the main issue with gusty up to 50 mph. Can`t rule out a few isolated gusts near 60 mph. Brief moderate to heavy rain will also accompany the thunderstorms. The showers/storms end by mid evening as the airmass stabilizes. Thunderstorms tracking south over western Nebraska could clip the far northeast corner of Colorado later this evening/tonight. These storms will be in a more moist and unstable airmass, with MLCAPE of 1000-2000 j/kg and be severe if the pass over the area. The upper level high that has been to our southwest will begin shifting eastward Friday as an upper level trough moves onto the Pacific Northwest coast. Temperatures continue to warm with highs expected to reach the lower to mid 90s across northeast Colorado. Some models show a subtle increase in moisture, others dont. If we see this increase, it would just increase the number of high- based showers and thunderstorms. Gusty outflow winds up to 50 mph will again be the main threat. Southwest flow aloft will increase Saturday throughout the day as the upper-level trough moves inland and the upper-level high shifts southeast of the Central Rockies. We will see one more day of very warm temperatures with highs in the lower to mid 90s over northeast Colorado. Moisture increases, mainly late in the day. This will lead to a better chance for showers and thunderstorms. On Sunday, southwest flow aloft will increase becoming somewhat strong for this time of year as the upper level trough moves across Montana. This will increase monsoon (mid/upper-level) moisture. However, with a lack of a cold front or easterly push low-level moisture will be limited. We still expect a round of scattered afternoon/evening showers and thunderstorms. Temperatures begin to cool, but remain slightly above normal. Much of the same is expected for Monday, except that a shortwave trough embedded in the southwest flow could bring a better chance for showers if it tracks over the region. For Tuesday through Thursday, southwest flow aloft will continue with the upper level high remaining southeast of the region and troughiness to our north. As for shower and thunderstorm chances, they decrease as the airmass dries. There may be one or two days with no convection, but it is too soon to tell when. && .AVIATION /06Z TAFS through 06Z Saturday/... Issued at 1137 PM MDT Thu Aug 27 2026 VFR conditions are expected through the TAF period. Drainage winds are established at DEN/APA and should continue through the overnight hours. A little more uncertainty with both the prevailing winds and convective potential for Friday. Statistical guidance follows a typical diurnal pattern, with a gradual clockwise turn to the winds during the morning hours before settling on a light north/northeast by the early afternoon. Scattered high-based showers will likely complicate this a bit, with inverted-V soundings favoring gusty high-based convection during most of the afternoon and evening. Have kept the PROB30 with only a few minor adjustments at this point. Once convection diminishes during the evening, we should see a quick return to drainage flow for Friday night into Saturday. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...WFO Pueblo AVIATION...Hiris