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107 FXUS65 KBOU 271117 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 517 AM MDT Sat Jun 27 2026 .KEY MESSAGES... - 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. - Warmer today with an isolated severe thunderstorm possible over the far northeast plains this afternoon into the early evening hours. - All areas will trend warmer and drier for Sunday, with little change through the middle part of next week. The only exception will be for a slight chance of thunderstorms over the plains on Tuesday. && .DISCUSSION /Through Friday/... Issued at 219 AM MDT Sat Jun 27 2026 A stg upper level storm system for late June will be over the nwrn US today and move into the nrn Rockies on Sun. This will allow for rather stg SW mid level flow to remain across the area today and Sun. For this aftn, a pseudo dry line will be over the far nern plains where MLCAPE will be around 2000 j/kg with decent shear. As a result, an isold svr storm will be possible mainly east of Sterling during the late aftn and early evening hours. Further west it will be dry and hot with gusty SW winds from the higher terrain across most of the plains. Highs will rise into the 90`s across most of nern CO except for the far nern plains where readings will be in the upper 80s. On Sun, it will be dry and hot with highs remaining in the 90`s across nern CO. Once again with decent mid level flow will see gusty SW winds across the higher terrain and portions of the plains. By Mon, an upper level trough will extend from the nrn Rokcies into California. This will allow for SW flow aloft to remain over the area. A weak cool front will move across the plains in the morning which will allow for slightly cooler temperatures across the plains. Overall there isn`t much low level moisture behind this front and with a cap in place, tstm chances look minimal across the plains. For Tue, SW flow aloft will continue as a disturbance moves from the Great Basin into Wyoming by Tue night. At the sfc, the low level flow will become southerly across the plains. As a result, this will allow some return of lower level moisture by aftn with a pseudo dryline setting up over the plains. If the cap can be broken, there would be at least a slight chc of tstms east of this boundary from late aftn through the early evening hours. Thus have kept in 20-30 percent pops over the nern plains. Further west it will remain dry from the I-25 Corridor across the higher terrain. Looking ahead to mid week, SW flow aloft looks like it will continue. Overall it looks mainly dry both Wed and Thu with highs in the 90`s across the plains. && .AVIATION /12Z TAFS through 12Z Sunday/... Issued at 512 AM MDT Sat Jun 27 2026 Winds were generally south but will become more SSW by 14z and gradually increase through the late morning with gusts up to 25 mph. By 20z, winds will go more SW with gusts from 30 to 35 mph thru 02z. By 02z winds should decrease and then go more SSW by 05z or 06z. VFR conditions will continue thru the period. && .FIRE WEATHER... Issued at 219 AM MDT Sat Jun 27 2026 Critical fire weather conditions will be in place across all of the high country today, as a much warmer and drier airmass moves into the region, 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. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from 11 AM this morning to midnight MDT tonight for COZ211>214-216>218. Fire Weather Watch from Sunday morning through Sunday evening for COZ211>214-216-218. && $$ DISCUSSION...RPK AVIATION...RPK FIRE WEATHER...RPK