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784 FXUS65 KBOU 170907 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 307 AM MDT Tue Mar 17 2026 .KEY MESSAGES... - Light alpine snow showers, producing a an inch or two of accumulation for the higher elevations through this morning. - Significant warm and dry period ahead from today through Saturday. All-time new March record high temperatures a good bet for the plains Thursday, Friday and Saturday. - Hot and dry weather will sustain prolonged high fire danger for portions of the plains today and Wednesday, then across much of the forecast area Thursday through Saturday. && .UPDATE... Issued at 257 AM MDT Tue Mar 17 2026 Winds have been gusting in the 50`s and 60`s across mtn and foothill areas with a few gusts up to 70 mph. Cross-sections showed favorable mtn top stability with cross-barrier flow in the 40-45 kt range. Mtn top stability should decrease by mid to late morning so expect winds to be not quite as stg. && .DISCUSSION /Through Monday/... Issued at 1159 PM MDT Mon Mar 16 2026 Current radar shows light snow showers across the northern Front Range mountains due to lingering mid-level moisture. Expect scattered snow showers to continue overnight and into early Tuesday morning, with only a couple of inches in additional accumulation. With 700-mb winds reaching up to 50-60 kts across the high terrain, blowing snow is likely through early morning, especially along the high mountain passes. Unfortunately, the ongoing mountain snow showers look to be the only chance of precipitation for the rest of the week. A well-defined upper level ridge in Southern California will begin to trek east Tuesday through Saturday, with northwest flow aloft bringing warm, dry and breezy conditions to the forecast area, along with a prolonged period of elevated-to-critical fire weather conditions (see fire weather discussion below). Anomalous heat will return to the region beginning Tuesday, with forecasted highs in the low-to-mid 70s across the plains and low 40s to upper 50s across the mountains/valleys. Expect warmer temperatures later this week as the ridge of high pressure continues east. Current ensemble solutions favor high temperatures in the low- to-mid 80s Thursday through Saturday (However, the GEFS still remains the coolest of the models, with high 70s to low 80s for later this week). With this trend, there is a good chance we will break record high temperatures later this week. Current high temperature records at DIA are: March 19: 81 degrees set in 1907 March 20: 80 degrees set in 1907 March 21: 78 degrees set in 1995 By Saturday/Sunday, flow aloft should weaken and become more zonal as guidance continues to indicate a shortwave trough trekking across the northern United States. A cold front associated with the system should bring cooler air mass to the region, with temperatures moderating to the low 60s. && .AVIATION /06Z TAFS through 06Z Wednesday/... Issued at 1115 PM MDT Mon Mar 16 2026 VFR conditions thru the period. Gusty WNW winds up to 35 mph will continue at BJC thru 08z and then should decrease by 08z. Winds will then increase again by 15z from the WNW and continue thru Tue aftn with gusts to 35 mph at times. DIA will maintain a WSW wind overnight and then turn more WNW by 16z or 17z with gusts up to 25 mph. By 19z expect a more NW direction with gusts from 30-35 mph thru the aftn. APA will be light drainage overnight and then go WSW by 14z. By 16Z winds will become more westerly with gusts to 25 mph thru 20z. After 20z expect a more WNW direction with gusts from 30-35 mph. By early Tue evening, winds will decrease at all three airports with wind directions WNW or NW. && .FIRE WEATHER... Issued at 257 AM MDT Tue Mar 17 2026 Critical fire weather conditions are expected across the northern and eastern plains today. Modeled Skew-T soundings indicate breezy northwest winds aloft mixing down to the surface by late morning/early afternoon. Wind gusts up to 35-45 mph are expected, with locally higher gusts closer to the Wyoming border. Relative humidity values will drop down to the mid-teens. A Red Flag Warning remains in effect from 10 AM through 8 PM and have added central and southern Weld county to the warning. Elevated-to-critical fire weather conditions return on Wednesday for the the northern and eastern plains. With the continued warming, minimum relative humidity values will range between 9-15% with winds gusting up to 25-35 mph at times. For this reason, have decided to issue a Fire Weather Watch. South Park could see elevated fire weather conditions as well. For the rest of the week, elevated-to-critical fire weather conditions are expected across the forecast area due to the anomalous warm and dry airmass. Recent moisture along the Front Range mountains should keep fuels from being susceptible to combustion. However, will need to continue to monitor the next couple of days. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from 10 AM this morning to 8 PM MDT this evening for COZ238-242>244-248>251. Fire Weather Watch from Wednesday afternoon through Wednesday evening for COZ238-242>244-248>251. && $$ UPDATE...RPK DISCUSSION...MAI AVIATION...RPK FIRE WEATHER...MAI/RPK