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826 FXUS65 KBOU 221850 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1250 PM MDT Sat Aug 22 2026 - Highest coverage of showers and storms expected today, along with a few severe storms and locally heavy rainfall this afternoon and evening. - Scattered afternoon and evening showers and storms through Thursday. A risk of a couple severe storms each day. - Temperatures settling back closer to (but still above) normal for Tuesday and Wednesday. - Gradual drying end of next week, with a trend to more summer heat through next weekend. && .DISCUSSION /Through Saturday/... Issued at 1249 PM MDT Sat Aug 22 2026 Satellite and radar shows pretty healthy convection developing across the Front Range Mountains and Foothills, while the airmass is still somewhat stable (per ACARS and SPC analysis) but increasingly moist over the plains. The increased moisture on the plains is being reinforced by a couple westerly moving surges, and dewpoints have held in the upper 50s and lower 60s east and north of Denver. The latest surge coming back through Elbert County will likely boost values over the Palmer Divide this afternoon, especially as we develop a surface cyclone in vicinity of Douglas or western Elbert County. That will aid moisture convergence and potential for convective initiation there, along with a risk of a landspout. Otherwise, stronger storms today will be capable of hail and strong winds, along with locally heavy rainfall as precipitable water (PW) values climb to 150-170% of normal and low level moisture remains abundant over the plains. As per typical, we still think the highest threat of strongest storms would be along/east of the convergence zone associated with the developing cyclone and points northward along/just east of I-25 - essentially covering all of the plains. A couple severe storms are likely due to MLCAPE increasing to 1200-2000 J/kg. Bulk shear is weak and less than 25-30 kts, however, so majority of the severe storms would tend to be pulse (brief). Storm motion will be rather slow at 15 mph or less given lack of flow aloft, which will lead to at least some minor flooding threats in a few spots. Overall progression will eventually be to the east across the plains into late evening, with potential for a generally weaker subsequent batch or two of storms behind the initial stronger ones that would have access to more instability. We still expect some gradual clearing overnight, but patchy stratus/fog possible across the plains given the very moist airmass. On Sunday, there is some drying noted as flow aloft turns a bit more westerly. However, we`re not convinced we`ll erode all the low level moisture across the plains. Even in the mountains we`ll still see enough to spark scattered thunderstorms, and then those storms will likely intensify as they move onto the plains as they encounter a richer, more unstable airmass. Bulk shear profiles are still marginal, but a couple severe storms will be possible given sufficient MLCAPE of 1000-1800 J/kg. Similar weather conditions will likely persist into Monday with little change in the overall pattern, moisture, and instability profiles. Temperatures will be rather warm yet, with highs in the 90-95 degree range over the I-25 Corridor and plains. There is better agreement of a weak backdoor cool front or two for Tuesday and Wednesday, offering up a few degrees of cooling and potentially more active weather over the Front Range and plains. Thursday and Friday are shaping up to be transition days into a drier and warmer environment with progressively less storm coverage, especially by Friday. Ensembles are consistent showing a return of summer heat for next weekend, with highs pushing into the mid 90s (30% chance of upper 90s) for the I-25 Corridor and plains as a stronger zonal flow aloft develops. That would also lead to increasing fire danger as we begin our journey toward autumn breezes. Unfortunately, temperatures will feel more like mid summer and humidities will drop in the drier westerly flow. && .AVIATION /18Z TAFS through 18Z Sunday/... Issued at 1131 AM MDT Sat Aug 22 2026 A boundary currently to the east of DEN and APA will continue to move westward towards each of those terminals. It now appears likely the boundary will get close enough to both of those terminals to bring stronger easterly winds than previously forecast. East winds could gust to around 20 knots. There is a slight chance (20%), however, that a DCVZ develops just to the east of DEN and APA that keeps winds more out of the northeast with lighter speeds. Storms are expected to develop this afternoon with the earliest possible storms at 19Z at BJC and 20Z at DEN and APA. The most likely time for storms to impact all terminals is between 22-02Z. Strong outflow winds are likely with gusts 40-45 knots. It is even possible (20%) that severe gusts above 50 knots occur at DEN or APA. Besides winds, there is a chance (40%) that visibility will be reduced to 2-4 miles and ceilings drop to 4,000-6,000 feet if a storm were to move directly overhead. In the evening, southerly winds are likely to develop at DEN and APA with a small chance rain showers move overhead with little impact. Drainage winds are expected for much of the night at all terminals. Normal wind patterns are expected throughout the day on Sunday. There will be less low level moisture in place and coverage of showers and storms will be lower as a result. However, an outflow boundary or two is still expected to impact the terminals late tomorrow afternoon and early evening. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...20 AVIATION...Danielson