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012 FXUS65 KBOU 071201 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 601 AM 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 /12Z TAFS through 12Z Wednesday/... Issued at 543 AM MDT Tue Jul 7 2026 South to southwest winds are in place at KDEN/KAPA with light and variable winds at KBJC this morning. Smoke is prevalent on webcams once again that is expected to reduce slant-range VIS and bring IMC conditions through at least the morning. Shower and storm coverage is expected to increase today, moving within the vicinity of the TAF sites by 19Z-21Z, impacting KBJC/KAPA followed by KDEN. These should be fairly high-based showers again, with CIG expected to remain at or above 10,000` AGL and DCAPE expected to be around 1500 J/kg across the area. Expect gusty outflows between 35-45kts possible with passing showers/storms. A few showers may persist in the vicinity of the TAF sites through around 5Z that may delay winds from settling into drainage. Low confidence in wind direction between the exit of storms and the development of drainage winds (expected by 6-7Z), but with storms expected to exit to the east, there is higher confidence in a more easterly component from outflows. Latest guidance suggests some slight improvements to smoke concentrations for tomorrow morning that increased confidence high enough to keep FU out of the TAF for the morning Wednesday. This could easily change depending on today`s fire behavior though, so will continue to be assessed through upcoming TAF packages. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...9 AVIATION...9