This content was originally published by the Longmont Observer and is licensed under a Creative Commons license.
In Brief:
As smoke drifts around the Front Range, a parade of cold fronts is on its way. The first cools us about 15F for Friday then the next drops us another 10F on Sunday. Chances of rain are present with both fronts, but not much should fall. Temperatures look too warm for snow. There is an 'over the horizon' storm mid-week next week. We'll see what that does later.
Update 10/18 4pm:
Everything is on track in the short term (in this discussion) but I do want to highlight the winds expected Sunday. Figure 1 update are the forecast winds in Colorado around noon on Sunday 10/20. That cold front is expected to be of the "Bora" variety. Definition from weatheronline.com: The bora is a cold and typically very dry and often gusty katabatic wind (fall-wind) from the north-[west*]. Bora winds can occur anytime during the year. However, the peak frequency occurs in the cold season (November - March).
*northwest for our part of the world.
End update 10/18 4pm.
Forecast Discussion:
There is some smoke from the Deker and Elk fires that is even dense enough to add a burning wood smell to the air in town (Figure 1). The approaching front may thin the smoke, but it will bring in smoke from other sources as well. Watch for a bit lower visibility when looking for the mountains.
By Friday noon, the front has swept down the state (Figure 2) passing Longmont around sunrise (Figure 3). There is a small chance of post-frontal showers. We cool 15F degrees or so on Friday with breezes.
The Longer Range Forecast:
The next front hits overnight Saturday into Sunday and cools us another 10F (Figure 3). This is powered by a fairly deep, but open (not a closed circulation) trough aloft (Figure 4). It will pass quickly without a prolonged cool down or chance for snow.
By noon Monday, the mountains will have picked up some nice snow, but Longmont seems to get skipped (even if there might be snow in the air overnight - Figure 5). You can see the next front and snow mid-week (if it comes to pass) in Figure 3. The accumulation through NEXT Monday still skips Longmont (according to the GFS). Keep rooting for snow!
