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420 FXUS65 KBOU 231902 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 102 PM MDT Sat May 23 2026 .KEY MESSAGES... - Isolated threat for severe storms this afternoon in the far northeast corner of Colorado. Wind and hail would be the primary hazards. - Warmer and drier this weekend, with only isolated showers and storms possible each afternoon/early evening. - Remaining mild next week, but scattered afternoon and evening showers and storms expected most days. && .DISCUSSION /Through Saturday/... Issued at 1253 PM MDT Sat May 23 2026 This morning`s upper-air charts show an upper-level low situated along the Canadian border over North Dakota and Minnesota, with the associated trough axis still stretching across eastern Colorado. 700 mb dewpoints show some lingering moisture remains east of the Rockies, but a swath of higher dewpoints remains just south and east of Colorado. The trough is expected to progress eastward through today with upper-level ridging expected to move overhead on it`s backside. A brief warming trend is expected to kickoff today, with afternoon high temps expected to hover near-normal across the forecast area, reaching values roughly 10 degrees warmer than yesterday`s highs. Expect low to mid 70s along the urban corridor, with 60s forecast for the high mountain valleys today before temps warm by another 10 degrees or so for Sunday. Precipitation chances are primarily anchored to the higher elevations today in the form of some high-based virga showers, and for the far northeast plains where the SPC has placed a sliver of our northeast corner in a marginal (1/5 risk level) for isolated strong to severe thunderstorm potential for wind and hail. The main severe potential will likely remain east of our forecast area where the majority of the hi-res guidance continues to show the higher dewpoints remaining, but if these slide a bit more westward like portrayed in a few of the deterministic models, with 35-45kt 500mb flow aloft, can`t rule out the potential for isolated severe hail or wind. There will also be potential for any of the aforementioned high-based showers that develop to bring gusty winds as they move off the terrain as DCAPE values between 800-1000 J/kg will be possible through the afternoon hours that could produce gusts up to 35-40 mph. Mild temps (mid to upper 40s) are expected across the majority of the lower elevations for the overnight hours, with the base of the foothills expected to be in the low 50s and the mountain valleys dropping into the 30s. For Sunday, it will be warm and mostly dry as the aforementioned warming trend continues. 700 mb temps are expected to increase to 9- 11C under a fairly zonal upper-level ridge. Temperatures are forecast to climb into the 80s along the urban corridor, approaching 90 across our northeast plains, and 60s to 70s for the high mountain valleys. We could see a few afternoon high-based showers/weak storms develop over the higher terrain that will likely be accompanied by some gusty outflows once again. From Monday onward, ensembles show a gradual increase in PWAT each day through the week, with the best moisture expected over the higher elevations. An upper-level low is likely to move ashore Southern California Sunday, progressing eastward and turning flow aloft over Colorado to the southwest by Monday morning, despite the broad upper-level ridge axis remaining in place across the Rockies. Monday is expected to be the warmest day of the week, with afternoon highs expected to reach 10-15 degrees above-normal across the plains. This will bring an uptick in showers and thunderstorms for the afternoon as PWAT values reach roughly 120-140% of normal along the mountains and up to 120% of normal for the plains, as the ridge axis shifts off the spine of the Rockies through the day. By Monday evening, an upper-level low will move ashore the Pacific Northwest and help amplify the ridge now over the Central Plains. This low is expected to drop southward and into the Great Basin where it`s expected to remain blocked (stationary) through the long term forecast period. Temperatures will turn back towards near normal as we have daily chances for showers and thunderstorms as the low remains just to our west through the week and PWAT values remain above normal through at least Thursday. && .AVIATION /18Z TAFS through 18Z Sunday/... Issued at 1230 PM MDT Sat May 23 2026 Current observations show light winds (