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538 FXUS65 KBOU 311819 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1219 PM MDT Mon Aug 31 2026 .KEY MESSAGES... - Better precipitation chances today, with another round of afternoon/evening showers and storms, a few may become severe over the plains. - Warmer and drier conditions expected from Tuesday through Friday. && .DISCUSSION /Through Sunday/... Issued at 215 AM MDT Mon Aug 31 2026 SW flow aloft will continue today thru tonight. Water vapor imagery shows one disturbance over nrn CO tonight which will move away from the area this morning. Meanwhile, a secondary disturbance embedded in the flow will move from nern AZ across wrn CO late this aftn/early evening and into WY by late evening/overnight. There will continue to be an influx of monsoon moisture across the area with PW values up to 150% above normal. Thus will see showers/tstms become likely by mid to late aftn over the higher terrain. Across the plains, MLCAPE will be around 1000 j/kg with bulk shear up to 30 kts. Overall, there will be some threat of wet microbursts from the stronger storms along with marginal large hail. Best timing of tstms will be from late aftn thru the mid evening hours. Storms will produce locally heavy rain in some areas but they will be moving along as flow aloft increases this evening. As for highs, readings will be near seasonal normals. On Tue, there will be a lingering chc of showers across the area in the morning hours. By aftn, drier air in SW flow aloft will move into the area which will lead to lower chances for showers/tstms. Highs will remain near seasonal normals. For Wed and Thu, dry air in SW flow aloft will remain over the area with only a low chc for aftn showers/tstms. Temperatures will be warmer as readings rise into the upper 80`s to lower 90s across the plains. By Fri thru next weekend, an upper level high build over the central US as an upper level low resides over the Pacific NW. This will allow for the flow aloft to become more SSW. Models eventually want to advect some monsoon moisture, from the swrn US, into the higher terrain by the weekend. If that happens then there would be an increasing chc for showers/tstms, mainly over the higher terrain. Across the plains, expect above normal temps to continue with just a slight chc of tstms next weekend. && .AVIATION /18Z TAFS through 18Z Tuesday/... Issued at 1219 PM MDT Mon Aug 31 2026 Current observations show light and variable (