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994 FXUS65 KBOU 311922 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 122 PM MDT Mon Aug 31 2026 .KEY MESSAGES... - Better precipitation chances today, with the potential for a few rounds of afternoon/evening showers and storms, a few may become severe over the eastern plains. - Warmer and drier conditions expected from Tuesday through Friday. - Return of better moisture by the weekend increasingly likely for the high country. && .DISCUSSION /Through Monday/... Issued at 117 PM MDT Mon Aug 31 2026 Southwest flow aloft continues pumping more monsoonal moisture into our area. Today will have the highest rainfall chances of the week as an embedded shortwave moves through overhead. This will bring a push of moisture set to arrive to our forecast area this afternoon and evening. In fact, showers and thunderstorms are already ongoing across the Four Corners region and Southwest CO as of 1pm. At the same time, a jet streak is departing the region to the east putting us in the favorable right entrance region this afternoon. It is important to note that SPC mesoscale analysis currently shows instability lacking across our area, which could limit the severe potential, especially for the I-25 urban corridor and adjacent plains. The main concern with storms today will be gusty and erratic outflow winds as well as microbursts capable of producing wind gusts of 40 to 50 mph as DCAPE is expected to be around 1000 J/kg. MLCAPE is forecast to reach around 1000 J/kg, mainly for the far eastern plains. 0-6 km bulk shear should be about 30 to 40 kts with the greatest shear expected in our eastern plains where temperatures have warmed into the mid 80s as of 12pm. Therefore, a low risk for hail of 1 to perhaps 1.5 inches in diameter exists for the far eastern plains. There is also a low flood threat given that the ingredients are in place, but storm motion should be rather quick this afternoon with mean wind around 30-40 kts- limiting the overall threat. A decent moist vertical profile for the area means PWATs of 150-175% of average for this time of year. Thus, burn scars, areas where storms linger, and locations that receive multiple rounds of heavy rainfall today would be most susceptible to minor flooding. The warm cloud layer depth is relatively shallow, further limiting the flooding threat. CAMs are in decent agreement that there will be at least two rounds of showers and storms this afternoon and evening. Showers and storms should overspread the southern high country as early as 2-3pm. The most widespread showers for the high country and Urban Corridor should be between about 4pm and 8pm. These should then push off to the north and east. An additional round or two of showers and storms is possible for the evening and overnight hours through about 2am tomorrow morning. Tonight, some low clouds and patchy fog are possible for the plains following the rain. Some light rain showers could linger into tomorrow morning for the plains, though the odds are rather low. High temperatures for today and tomorrow will be near average- in the mid 80s for the plains. Some isolated storms are possible for the high country and areas south and east of Denver tomorrow afternoon. There will likely be a low threat for severe weather near the Palmer Divide with any storms that could form, but moisture and lift will be lacking compared to today. The high pressure shifts off to the mid-Atlantic and Southern US shutting off the monsoonal moisture feed into our area by Wednesday. High temperatures will return to above average- in the mid 80s and low 90s across the plains- for the end of the week and into the weekend. Little to no rainfall is expected through at least Friday. By the weekend, south to southwest flow aloft could return. Moisture from a tropical disturbance in the Pacific could also be pulled into the Western US, but as of now the deepest moisture looks to miss our area to the west. Thus, the highest rainfall chances should stay confined to the high country until Sunday or Monday. && .AVIATION /18Z TAFS through 18Z Tuesday/... Issued at 1219 PM MDT Mon Aug 31 2026 Current observations show light and variable (