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114 FXUS65 KBOU 211900 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 100 PM MDT Sat Mar 21 2026 .KEY MESSAGES... - Record heat and critical fire weather conditions continue this afternoon and evening. Several sites may see 90F high temperatures. - Brief drop to near normal temperatures Sunday. - Return of unseasonable warmth, potential record heat, and more fire weather concerns again by Tuesday and Wednesday. Record heat increasingly likely (>80% chance) across the Denver metro. && .DISCUSSION /Through Saturday/... Issued at 1235 PM MDT Sat Mar 21 2026 Today`s forecast largely remains on track, as we continue to simply watch the temperatures across most of the forecast area. There are already some rather impressive temperatures noted across the I-25 corridor and foothills as of the time of this AFD (1230 PM). Nearly every ASOS/AWOS/RAWS station below 6,500ft has already made it into the low 80s, with a few >85F temperatures noted at BDU/GXY/EIK/LMO. We`ve been a touch slower to fully mix out some of the lingering near surface moisture, but observations from the high country suggest that this won`t be the case by mid-afternoon. Winds may also be a little slower to work their way east, but there should still be a push of wind across the I-25 corridor between 3-7 PM. Meanwhile, we`re starting to see more wind across the high country, where a Red Flag Warning is already in effect. Like the plains, most locations haven`t completely mixed out yet, but a continued increase in winds (and subsequent decrease in dew point/RH) is still in the forecast through the evening hours. A cold front should push southward across the lower elevations after midnight tonight, bringing cooler temperatures and an increase in moisture. Sunday will at least feel a little closer to normal, with highs in the 60s and weaker easterly winds across most of the plains. There`s maybe just enough moisture for a few light rain/snow showers across the Front Range but chances for measurable precipitation are still low (generally 10F temperature departures are near 50-90%, with higher confidence of above normal temperatures across the mountains. && .AVIATION /18Z TAFS through 18Z Sunday/... Issued at 1146 AM MDT Sat Mar 21 2026 The west-northwesterly winds aloft will eventually get down to the surface later this afternoon with the strong heating. Will go with gusts up to around 25 knots. Will go with lighter west winds by mid evening until the cold front moves in after midnight. Left the 09Z timing of that feature in the TAF. Gusts may reach 20 knots behind the FROPA. Cross section on some of the models still hint at a deck of Stratus after the front goes through. Will leave that going in the TAF for now but I am somewhat skeptical. && .FIRE WEATHER... Issued at 1235 PM MDT Sat Mar 21 2026 Critical fire weather conditions are continuing to develop across the higher elevations and into the far western I-25 corridor this afternoon, and should persist through most of the afternoon and evening hours. Only minor tweaks to the forecast were made in this period and no changes to the Red Flag Warning were made today. Cooler temperatures and weaker winds should limit the overall fire danger on Sunday and Monday. As a ridge begins to redevelop to the southwest and zonal flow increases, another warming/drying trend is expected by Tuesday/Wednesday. Elevated to critical fire weather conditions look likely both days, and may extend into Thursday depending on the timing of our next cool front. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 10 PM MDT this evening for COZ211-213>216. Red Flag Warning until 10 PM MDT this evening for COZ238>245-248- 250. && $$ DISCUSSION...Hiris AVIATION...66 FIRE WEATHER...Hiris