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276 FXUS65 KBOU 271958 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 158 PM MDT Mon Jul 27 2026 .KEY MESSAGES... - Some relief from the heat today, with increasing chances of showers and afternoon/evening thunderstorms. - Scattered to numerous showers and storms with locally heavy rain Tuesday and Wednesday. Temperatures settle back closer to normal. - Drying out again later in the week. Heat returns for next weekend. && .DISCUSSION /Through Monday/... Issued at 145 PM MDT Mon Jul 27 2026 We had an MCV over the area this morning, which provided some cloud cover and light rain across a good portion of the area. The cloud cover and rain has kept temperatures in our area quite a bit cooler than surrounding areas (as of 1PM a station in northern Weld County was still at 75 degrees). The cooler temperatures and cloud cover will limit instability in portions of our area for this afternoon. The heavier cloud cover is pushing to the northeast, with good clearing in the urban corridor. Showers and thunderstorms are expected to form this afternoon across the higher terrain, pushing east into plains during the evening hours. A few of the storms this evening could still be strong to marginally severe, but at this point the main hazard looks to be heavy rainfall leading to flash flooding, with a secondary hazard of strong winds. The rain chances and flooding threat will continue into Tuesday and Wednesday. The upper level set up will remain similar, with a weak disturbance or two moving through the upper level ridge aloft each afternoon. At the surface, PWs are forecast to remain around 150% to 200% of normal. The flooding threat is expected to increase for tomorrow, as the warm cloud layer depth increase slightly and rainfall from today makes soils more prone to flooding. The coverage tomorrow also looks a bit higher, with potential for a few strong storms with heavier rainfall rates compared to today. Instability and shear will be decent enough for a few marginally severe storms as well. The main hazards tomorrow will likely be strong winds and heavy rain. The one limiting factor for heavy rain potential will be the cloud layer winds increasing a few knots for Tuesday, which could help storms move slightly faster. A similar set up will exist for Wednesday as well. The flooding potential for Wednesday will depend heavily on how much rain falls today and tomorrow. Areas that see heavy rain on today and Tuesday will be more prone to flash flooding on Wednesday. Storm motions remain on the elevated side for Wednesday, but the high moisture and previous rainfall will lead to a 3rd day of flash flooding potential. While precipitation is not guaranteed each day at every location, there is a high chance (>70%) that over the next 3 days many locations in our area will see at least 0.25 inches of rain, with a good chance that a few localized areas see multiple inches of rain. Right now, the best chance for these higher rain amounts are in our eastern plains counties. The upper level ridge will begin to shift more to the west for Thursday into the weekend, putting us in northwest flow aloft and decreasing the moisture over the area. This will significantly reduced our rain chances for the plains, with the potential for some isolated to scattered activity lingering in the higher terrain. The thermal ridge will remain off to our west through the work week, keeping temperatures in the low to mid 90s for much of the plains. The thermal ridge will start to shift more eastward by the end of the week as the upper level ridge starts to tilt and push more northeast. && .AVIATION /18Z TAFS through 18Z Tuesday/... Issued at 1108 AM MDT Mon Jul 27 2026 Clouds are beginning to break up behind a disturbance that moved across this morning. Still expect sct tstms to develop around 22z and may linger thru 02z. After 02z can`t rule out some widely sct -shra/-tsra so will continue with prob30 until 06z. Brief gusty winds from 30 to 40 mph will be possible and if a stronger storm were to occur then visibility could drop to 3-5 miles as well. As for winds they should become more ENE by 20Z and continue thru the aftn. By 02z winds will become more SE and then go to drainage by 06z. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...AP AVIATION...RPK