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106 FXUS65 KBOU 102353 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 553 PM MDT Wed Jun 10 2026 .KEY MESSAGES... - Elevated to critical fire weather conditions across the plains this afternoon and evening with warm, dry, and breezy conditions. - A brief cooldown for Thursday behind this evening`s cold front. - Critical fire weather conditions likely across the high country Friday and Saturday. - A more substantial cooldown starting Sunday, with a better chance of showers and storms. && .DISCUSSION /Through Wednesday/... Issued at 1138 AM MDT Wed Jun 10 2026 Relatively quiet conditions are noted across the forecast area this morning, with just a few clouds noted on satellite. Once again, gusty westerly winds are having a difficult time mixing down into the I-25 corridor and plains, with a diffuse/broad Denver cyclone still firmly entrenched across the metro. While gusty winds have been slow to develop, model guidance is insistent that this will happen sometime in the next couple of hours. This includes the NAM/3km NAM whose boundary layer schemes typically under-mix in weakly subsident patterns. While the Red Flag Warning is pretty borderline/marginal, it did not seem necessary to make any changes to that highlight. Next up on the forecast agenda is well-defined cold front moving through the region late this evening into the overnight hours. Guidance still moves this through the Denver area by 10PM to midnight tonight... and will keep temperatures tomorrow about 5-10F cooler across the plains with some modest cooling across the high mountain valleys as well. The post-frontal airmass is very dry and Thursday should be mostly sunny across the forecast area. Zonal flow is expected to persist for Friday and Saturday, with the mid-level thermal ridge expanding back into the state. For the plains, this will mean a continued period of warm and very dry conditions. Across the higher elevations, the mid-level flow is expected to remain strong enough for gusty winds each afternoon... and combined with the hot/dry airmass will lead to increasing fire danger. See the Fire Weather discussion below for additional details. A pronounced (albeit brief) pattern change is expected to end the weekend, as a strong shortwave trough dives in from the Northern Rockies. Widespread showers and a few thunderstorms are forecast Sunday afternoon and evening behind a surface cold front, with decent changes of meaningful rainfall (30-60% chance of >0.10") across most of the forecast area. Temperatures will be substantially cooler... with forecast highs in the upper 60s to low 70s on both Sunday and Monday. Forecast certainty decreases by next week. A large ridge is expected to begin building to our southwest, while a couple shortwaves reinforce the northwesterly flow across most of the Central/Northern Great Plains. Our forecast area looks to be stuck somewhere in the middle of these two features, leading to a rather uncertain temperature forecast. Most ensemble guidance favors a couple of warmer days during the middle of next week, with deterministic forecasts wobbling back and forth a bit from run to run. && .AVIATION /00Z TAFS through 00Z Friday/... Issued at 527 PM MDT Wed Jun 10 2026 VFR conditions expected through the TAF period. East to southeast winds are expected this evening before a cold front moves through between 05-07Z. This cold front may initially have wind gusts up to 35 knots at DEN but the winds will weaken slightly throughout the overnight period. During the day on Thursday, a Longmont anticyclone will develop. This will turn winds more to the east-northeast at DEN and east at BJC. Sporadic gusts may reach 20 knots mainly during the middle of the day. Southeast winds are expected Thursday evening before a return to drainage overnight. && .FIRE WEATHER... Issued at 1138 AM MDT Wed Jun 10 2026 Critical fire weather conditions are likely across at least a few portions of the plains this afternoon. Near critical fire weather conditions have already been observed from the Cheyenne Ridge into far northeastern Colorado this morning. Gusty westerly winds should become more widespread across the lower elevations this afternoon as better mixing develops. Recent forecast trends have held onto just a little bit more moisture than previously expected... and while there may be less overlap in wind/RH compared to previous forecasts, we did not opt for any changes to the existing Red Flag Warning today. Critical fire weather conditions are likely to develop across portions of the high country by Friday and Saturday. 30-40kt 700-500mb flow in a broadly subsident regime combined with a very dry airmass and above normal temperatures should lead to widespread elevated to critical conditions there... with weaker winds limiting fire danger across the plains. Although fuel susceptibility appears to be somewhat mixed across the mountain valleys, we`ve issued a Fire Weather Watch for North Park and Middle Park where the flow aloft is strongest. Additional headlines may be needed both Friday and Saturday. && .BOU WATCHES/WARNINGS/ADVISORIES... Fire Weather Watch from Friday morning through Friday evening for COZ211-213. Red Flag Warning until 8 PM MDT this evening for COZ240>248-250- 251. && $$ DISCUSSION...Hiris AVIATION...Danielson FIRE WEATHER...Hiris