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758 FXUS65 KBOU 160012 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 612 PM MDT Sat Aug 15 2026 .KEY MESSAGES... - Another round of showers and thunderstorms this afternoon and evening. Heavy rainfall and flash flooding are the main threats today. A few thunderstorms could become severe, with strong winds and hail possible. - Monsoon moisture lasts through Sunday, bringing scattered showers and thunderstorms again tomorrow. - Warming and drying trend for Monday and Tuesday. - Another active day possible middle of next week. && .DISCUSSION /Through Saturday/... Issued at 103 PM MDT Sat Aug 15 2026 The wetter weather pattern will continue on through this weekend. For today, there is a risk for severe weather and flash flooding. The eastern plains should be located near the right entrance region of a jet over the central US with a small disturbance expected in the flow aloft. GOES-19 satellite imagery shows a cirrus shield currently over the mountains that could initially inhibit convective development. Nevertheless, convective development is starting to occur across the foothills and in Larimer county. We expect showers and thunderstorms to develop across the foothills early this afternoon and move into the I-25 corridor by mid-to-late afternoon. These storms will then move off to the east in the late afternoon and early evening. The previously mentioned cirrus shield could hinder rain coverage and/or push this timing a bit later. The biggest threat for today will be heavy rainfall with some episodes of flash flooding possible across the area. The Weather Prediction Center highlights the foothills, I-25 corridor, and the eastern plains in a slight (2/4) risk for excessive rainfall for today. Several ingredients are in place for this threat. Thus, a Flood Watch is in effect from 2pm to 10pm this afternoon and evening. See the hydro discussion for more details. The Storm Prediction Center highlights the plains in a slight (2/5) risk. MLCAPE values are forecast to be around 1000-1200 J/kg and 0-6 km shear will be around 30-40 kts. Large hail and damaging winds are possible from storms today, with the highest chances along the Palmer Divide. Tomorrow will bring similar threats as today, though we expect less coverage of thunderstorms. Thus, the threats will be more localized in nature. MLCAPE and bulk shear values are forecast to be lower than today. The highest chances for showers and thunderstorms tomorrow should stay along/near the Palmer Divide, but there will still be scattered storms possible for most of our plains. High pressure will shift closer to our area for Monday and Tuesday further lowering rain chances and raising temperatures to around 90 degrees for the plains. By Wednesday, high pressure should shift off to the southwest, opening the door for a disturbance to move through the flow aloft and bringing back some isolated to scattered rain chances. This will only be a brief break as high pressure will start to build over the Four Corners region. Temperatures are expected to return to the low to mid 90s across the plains for the end of the week and into next weekend. && .AVIATION /00Z TAFS through 00Z Monday/... Issued at 610 PM MDT Sat Aug 15 2026 Storms have mostly moved out of the Denver metro area, though some lingering showers and wind gusts may remain this evening through 02Z. Winds will become light and variable behind today`s convection, with some mild S-SW drainage starting around 09Z. The main concern overnight and into the early morning hours, around 12-14Z, will be low ceilings and potential fog (60% chance), particularly over KDEN. Models are in fairly good agreement on moisture lingering in the low levels at KDEN, prompting a TEMPO for fog and low visibility. Low stratus could also be advected into the vicinities of KAPA and KBJC, though confidence remains lower to the west of KDEN at this time. Prevailing winds will remain light (051. && $$ DISCUSSION...MV AVIATION...Striplin HYDROLOGY...MV