This content was originally published by the Longmont Observer and is licensed under a Creative Commons license.
Forecast Discussion:
It is a bright, but chilly, Saturday - great for putting up Christmas Lights. In Figure 1, the front has swept back down to Mexico and the rain is in middle Kansas and east (Longmont is the pink dot again). The trough that is responsible for this storm is already into middle Kansas as well (red line, the pink dot is Longmont, and the pink line should be blue... bad software! - Figure 5).
From the cooperative observers at CoCoRaHS - there was a trace to a coating of snow in Estes Park, an inch in the northern mountains above Ft. Collins and a trace on the north side of Ft. Collins: Figure 2. Figure 3 has the closest snow being just a trace in the mountains above Boulder. But we did get about a 1/10th of an inch of rain (Figure 4). The models two days ago nailed it well!
The Longer Range Forecast:
The current upper air map (previously mentioned Figure 5) shows a ridge on the two coasts and a trough in the middle. When the ridge to ridge distance is about equal to the width of the U.S., the pattern doesn't move much (troughs and ridges stop really moving west to east).
In figure 6, our northwest flow aloft is still in place (Longmont is the pink dot) and the two ridges have just inched eastward a bit. But by Thursday night (Thanksgiving!) the ridge is just 10's of miles closer - meaning continued seasonal weather for our fair city.
Thanksgiving Forecast: A high of 68F, a low of 44F. We'll see light westerly winds and mostly clear skies. Give thanks!
