National Weather Service Forecast Discussion |
Thornton Weather Forecast Today's Forecast Story |
855 FXUS65 KBOU 221951 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1251 PM MST Sun Feb 22 2026 .KEY MESSAGES... - Slightly warmer today, before another big warm-up for the upcoming work week. - Strong winds expected along the Front Range and foothills on Tuesday. - Snow chances return to the mountains mid-week. - Potential for multiple days of elevated to critical fire weather conditions in the plains this coming week. && .DISCUSSION /Through Sunday/... Issued at 1248 PM MST Sun Feb 22 2026 Dry conditions will persist and temperatures will continue to warm into Tuesday as upper level ridging builds over the area. A big concern this week will be the high wind potential on Tuesday. Models are showing very strong winds at ridge top and looking at cross sections and soundings, there is potential for a mountain wave to develop. The ingredients that will help the mountain wave development: Models are showing ridge top winds out of the WNW around 70 to 85kts on Tuesday (85kts is almost 100mph). Sangster gives us a GJT to DEN MSL difference around 13 to 14mb in the afternoon. Mountain top lapse rates are generally around 4 to 6 C/km. The ingredients that are a little more borderline: A few models are hinting at the potential for a stable layer around 600 to 500mb, however the inversion/stable layer doesn`t look super great for a mountain wave. But models typically struggle this far out with the placement and strength of the inversion (so I take this with a grain of salt). QG subsidence is on the weaker side of things, however we will be on the periphery of the right exit region of the jet, giving us some weak subsidence. Finally, there is no evidence of a critical layer, but wind shear above mountain top does look weak enough to support some mountain wave amplification. In summary, conditions look favorable for very strong winds in the mountains, with the potential for mountain wave enhancement to push strong winds east down the slope. The eastward extent of the very strong and damaging winds is the most uncertain part of the forecast. Hopefully we`ll start to get a better idea of the eastward push as the high res models come in over the next day or so. We decided to go with a High Wind Watch for the higher elevations of the Front Range and the northern Foothills. But we may need to add additional zones with future forecast packages. Now for the winds on the other side of our forecast area. The 700mb jet looks to set up near the CO/WY/NE border on Tuesday. These stronger winds aloft could mix down towards the surface, creating wind gusts around 40 to 50mph in the northern plains of Colorado. Right now, there is a low chance (035. && $$ DISCUSSION...AP AVIATION...MAI