Thursday, September 21, 2017
An anomalously large trough of low pressure stretching from the central Canadian plains southwestward to almost Baja will affect our weather over the next week. Ahead of the trough, strong southwesterly flow has brought above average temperatures, sunny skies and wind to the Steamboat Springs area today.
There will be many moving pieces to the forecast as upstream Pacific energy contributes to several centers of circulation forming within the trough, with some of them being reabsorbed as they travel to the northeast, while others further stretch the trough to the southwest while reluctantly moving it eastward toward the Rockies.
Temperatures should stay warm through tomorrow morning ahead of gradually cooling temperatures through the weekend and into next week. The very slow movement of the trough will preclude any distinct cold front, but the slow cooling of the atmosphere combined with waves of energy moving over our area will contribute to an extended period of cool and showery weather.
There may be some showers Friday, though the heavier and more persistent precipitation will wait until Saturday and Saturday night when the trough is closer to our area and ejecting pieces of energy travel over Colorado.
There may be some dry air that mixes with the trough, possibly allowing for a break in the unsettled weather for a time on Sunday, before an unconsolidated center of circulation moves northeastward across Colorado later Sunday and Monday and brings another push of cooler air and storms.
Additional upstream Pacific energy crossing the West Coast regenerates the southern end of the trough early in the week, and though the coolest temperatures of the storm will occur over our area then, precipitation looks to become much lighter as the week progresses.
Right now, numerical models have the last push of cool air occurring around the end of the work week, and this finally moves the storm complex east of our area. A ridge of high pressure is advertised to bring much warmer and drier conditions for the following weekend.