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854 FXUS65 KBOU 071825 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1225 PM MDT Tue Jul 7 2026 .KEY MESSAGES... - Increased moisture expected to bring an uptick in shower and storm coverage this afternoon and evening, with an isolated severe threat along the Cheyenne Ridge. - Higher probabilities of thunderstorms with a few strong to severe storms possible from the Front Range eastward on Wednesday and Thursday. - Isolated dry thunderstorms in mountains could spark new wildfires. - Heat wave arrives this weekend, with minimal chance of any thunderstorms for heat relief. && .DISCUSSION /Through Monday/... Issued at 219 AM MDT Tue Jul 7 2026 Water vapor imagery shows moisture wrapping around an upper-level ridge centered near the Four Corners early this morning. While the better moisture will pass to our north, some mid-level and upper-level moisture will make it into Colorado by this afternoon, where high-based storms and showers are expected to develop and move from west to east across the forecast area. Isolated dry lightning will be possible across the higher elevations through the afternoon. Gusty outflows will be the main hazard for today`s convection, with forecast soundings showing around 1500-1700 J/kg of DCAPE, and CAMs showing storms becoming linear as they propagate eastward across the plains. The SPC has highlighted areas along the Cheyenne Ridge with a Marginal Risk for today (1/5 risk level) for an isolated severe wind gust and hail threat, though the hail threat is expected to be minimal. Shear will be a limiting factor for more organized storms today, with 0 to 6km bulk shear ranging between 20-25kts, but the aforementioned DCAPE values would support potential for severe winds between 60-70mph. Temperatures will be a few degrees cooler than Monday, but remain in the mid to upper 90s across the plains. Patchy smoke will persist along and east of the Front Range. Storm coverage and strength will increase on Wednesday and Thursday with higher instability and shear allowing for more organized storm potential. CAMs show between 700-1400 J/kg of MLCAPE across the plains on Wednesday, with the NAMNEST pulling the higher instability all the way west to the urban corridor (dewpoints in the 60s) where the HRRR keeps it primarily in the far northeast corner (dewpoints in the 50s). The RAP seems to split the difference, which would be aligned with the latest SPC assessment where they have issued a Slight Risk for areas along the Cheyenne Ridge to the NE/KS border for wind and hail, which seems reasonable at this time since 0-6km bulk shear is also expected to increase to 30-40kts in this same area. A slight uptick in shear (30-45kts) is expected on Thursday that will bring another day of a few strong to severe storms across the plains, though the greater moisture is expected east of the urban corridor, where the SPC has outlined a Marginal Risk for their Day Three Outlook. Temperatures will gradually cool down each day, with Thursday likely seeing afternoon highs sub 90F across the plains. Precipitation chances will begin to diminish on Friday as the highly advertised upper-level ridge begins to build over the Rockies. There will likely still be enough residual moisture in place for some afternoon convection, but subsidence and lacking shear will likely limit any real organization. Temperatures will begin to increase, but a more noticeable warming is expected on Saturday and into early next as temperatures reach for the triple-digits. Precipitation chances will be limited under strong subsidence. && .AVIATION /18Z TAFS through 18Z Wednesday/... Issued at 1223 PM MDT Tue Jul 7 2026 Current radar imagery shows a cyclone centered southeast of KDEN, east of KAPA. As such, we expect winds at KDEN to remain light and easterly before turning to the ENE-NE around 20Z. Winds at KAPA and KBJC are light and variable at the moment but likely to keep a northerly component through the afternoon (more NE for KBJC). An increase in cumulus cloud coverage is already being observed with showers starting to develop over the foothills. We have kept the TEMPO for -TSRA between 20Z and 24Z for the three airports, although high-based showers may reach the vicinity of KBJC and KAPA as early as 19Z. The primary concern with today`s storm activity will be dry microbursts capable of producing erratic wind gusts up to 40KT. Variable gusty winds may linger into the early evening (00Z-03Z) as outflow boundaries from storm activity over the eastern plains reach the Denver metro area. Light S-SSW winds are expected to return by midnight and persist through the early morning. A very similar setup will be in place tomorrow afternoon where we expect high-based showers developing over the Denver metro with the primary threat being gusty outflows (35-40KT gusts). Wildfire smoke concentrations will continue to impact slant-range visibility at least through sunset this afternoon. However, model guidance continues to suggest decreasing concentrations due to a shift to westerly/northwesterly flow at the mid-levels. Therefore, we have kept smoke out of the TAF for tomorrow. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...9 AVIATION...AA