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078 FXUS65 KBOU 270011 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 611 PM MDT Fri Jun 26 2026 .KEY MESSAGES... - Scattered showers and thunderstorms return this afternoon, and a few may become strong to severe in the plains. - Widespread and prolonged critical fire weather conditions will be present in the high country this weekend as warm, dry and windy conditions develop, continuing at times into early next week. - All areas will trend warmer and drier this weekend, with little change into next week. && .DISCUSSION /Through Friday/... Issued at 146 PM MDT Fri Jun 26 2026 Early afternoon convection has been a bit more feisty than originally anticipated. The latest SPC Mesoanalysis shows just enough of a favorable combination of CAPE (>1000 SBCAPE) and shear (effective layer shear ~30kt) that`s led to a few stronger updrafts on the west metro, southern Foothills, and Palmer Divide. The environment is marginally more favorable along and east of I-25, so it appears reasonable to expect a gradual increase in the severe threat over the next few hours as storms push off to the east. ACARS data and KFTG VAD show largely straight line hodographs, suggesting that multicell convection and splitting supercells will be the predominant storm modes through the afternoon and evening hours as activity shifts into the eastern plains. A prolonged period of elevated to critical fire weather conditions is expected this weekend into next week. As a large trough stalls across the northwestern CONUS, strengthening dry, mid-level flow will lead to warm and windy conditions, especially across the higher elevations. Temperatures across the plains are likely to reach the 90s both Saturday and Sunday, with mid-90s possible across the Denver metro. The overall pattern is not expected to change significantly next week, with a persistent trough across the northwestern CONUS and a large ridge firmly anchored near the Ohio Valley. That will leave Colorado in a mostly dry pattern with south/southwesterly flow aloft. A shortwave or two rippling through the trough to our northwest, we may see a weak cold front or two attempt to work into the region. However, the model consensus strongly favors above normal temperatures and dry conditions continuing through the next several days. && .AVIATION /00Z TAFS through 00Z Sunday/... Issued at 607 PM MDT Fri Jun 26 2026 Current radar imagery shows the strongest thunderstorms are now to the north and east of the Denver metro area. There are still a few showers developing over the foothills although they appear to be weakening as they move off the terrain. Nevertheless, a shower in the vicinity of the airports cannot be completely ruled out, but the likelihood has decreased (20% chance). Shower activity should end by 03Z, with strong S-SSW flow at KDEN and KAPA (gusts up to 25KT) in place through at least 06Z. Southerly drainage winds will prevail at KDEN and KAPA overnight while KBJC becomes light and variable. No precipitation is expected tomorrow, and skies will remain mostly clear. The main concern will be gusty southwest winds starting mid- morning, between 14Z and 16Z, and gusting up to 25-30KT. These gusty winds are expected to decrease shortly after sunset, at around 03Z. && .FIRE WEATHER... Issued at 146 PM MDT Fri Jun 26 2026 Critical fire weather conditions remain likely across all of the high country on Saturday. A much warmer and drier airmass moves into the region during the day, with winds also strengthening considerably across the higher elevations. Relative humidity is expected to fall to around 10-15% during the afternoon with wind gusts of 35-50 mph possible. The warm, dry, and windy conditions will continue on Sunday across much of the same area. There may be some very modest improvement to minimum humidity values across the northern mountains, but critical fire weather conditions are still likely to continue. The pattern is not expected to change significantly next week, with elevated to critical fire weather conditions possible each day. There were two changes of note with this afternoon`s forecast package. First, a Fire Weather Watch was issued for Sunday across much of the high country. Second, the southern Foothills fire weather zone was added into Saturday`s Red Flag Warning and Sunday`s watch after some additional coordination with fuels experts. While the northern half of the zone has seen significant rainfall over the past few days, the southern half of the zone remains very susceptible. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from 11 AM Saturday to midnight MDT Saturday night for COZ211>214-216>218. Fire Weather Watch from Sunday morning through Sunday evening for COZ211>214-216-218. && $$ DISCUSSION...Hiris AVIATION...AA FIRE WEATHER...Hiris