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972 FXUS65 KBOU 172026 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 226 PM MDT Wed Jun 17 2026 .KEY MESSAGES... - Critical fire weather conditions today across the mountains and valleys. - Elevated fire weather conditions in the mountains and valleys on Thursday and Friday with critical conditions expected on Saturday. - Severe storms possible across the far northeast corner on Saturday. - Scattered coverage of showers and storms on Sunday and Monday. && .DISCUSSION /Through Wednesday/... Issued at 204 PM MDT Wed Jun 17 2026 A cold front moved through the eastern plains of Colorado this morning reducing the heat today. While many areas in downtown Denver reached the low 90s this morning before the front, most of the afternoon will be spent in the upper 80s. The high temperature forecast was decreased by 2-4 degrees across the plains. The Red Flag Warning is verifying in the mountains and mountain valleys as Berthoud Pass is still gusting to 53 mph. No change was made to the warning. A secondary push of cooler air will arrive this evening. This will drop temperatures into the 50s across the plains tonight. It`s possible that a rain shower or two develops across the far northeast corner of Colorado tonight but no impacts are expected. Northwesterly flow aloft will continue on Thursday with a slight increase in 500 mb heights. High temperatures across the plains will reach the upper 80s under mostly sunny skies. The mountains and valleys will be warm and dry again but parameters for fire weather conditions are marginal so no highlights were issued. A ridge aloft will move more directly over Colorado on Friday. Highs will reach the upper 80s again across the plains. There may be just enough moisture for a few light showers and storms mainly over the Palmer Divide and southern foothills. On Saturday, a shortwave trough will move across Colorado during the latter half of the day. There will be plenty of warm air aloft and mostly sunny skies over the I-25 corridor and adjacent plains that temperatures will reach well into the 90s. Out on the eastern plains, there will be a dryline that sets up near Sterling to Akron. East of this line, there will be strong instability with over 3,000 most-unstable CAPE possible. The shortwave and dryline will provide enough forcing to create strong to severe storms. The Storm Prediction Center has far northeast Colorado in a slight risk of severe storms which seems adequate for day 4. Much more moisture will be in our forecast area on Sunday and Monday and with a couple of shortwave troughs moving overhead, scattered showers and storms are expected. && .AVIATION /18Z TAFS through 18Z Thursday/... Issued at 1139 AM MDT Wed Jun 17 2026 VFR conditions should prevail through the TAF period, with winds the main concern through Thursday morning. Fairly strong cold front pushed through the terminals between about 15-17z this morning. East/northeast winds remain in place across virtually all of the I-25 corridor at this point, which very few deterministic models had occurring at any time today. Have hedged almost entirely on the ECMWF/RGEM solutions which maintain a light NE component this afternoon, before winds are reinforced by another front this evening (~02-04z). We can`t entirely rule out the redevelopment of WNW winds across the metro this afternoon... with the best chance of seeing that at BJC. Tonight`s front will still be mostly dry, but there could be a bit of mid-level cloud cover developing by early Thursday morning. Winds Thursday AM should slowly shift back to the south or southeast, with a weak cyclone/shear zone developing by Thursday afternoon. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 8 PM MDT this evening for COZ211>214-217- 218. && $$ DISCUSSION...Danielson AVIATION...Hiris