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898 FXUS65 KBOU 172329 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 529 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 /00Z TAFS through 00Z Friday/... Issued at 525 PM MDT Wed Jun 17 2026 VFR conditions should prevail through the TAF period. Winds have maintained an easterly component today, though speeds have slowly diminished over the last couple hours. Still expect the arrival another front with a push of NE/NNE winds by around 03z this evening. We could end up with a few hours of FEW-SCT060 overnight into early Thursday morning behind the front but little else is expected. Winds should weaken and try to turn southeasterly by Thursday morning. Quiet weather is expected again on Thursday. Guidance is in good agreement that a diffuse cyclone or broad shear zone will develop by the late morning or early afternoon. Chances are BJC remains light north/northeast and APA maintains a southeasterly direction... with DEN ending up somewhere in between. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 8 PM MDT this evening for COZ211>214-217- 218. && $$ DISCUSSION...Danielson AVIATION...Hiris