Unsettled Pattern

Short Range-
Several waves are setup to come through the area during this unsettled period. The first wave or disturbance will pass with a cold front from the north on Tuesday night 11-27. Behind it NW flow will provide a drying atmosphere giving way to little moisture on the Eastern slope. Cold air with this front will remain for most of the week as we have a very weak ridge setting up behind the frontal passage.

Long Range-
The big storm setup for Colorado that I have been watching for over a week is beginning to decay in the models. On Friday the shallow ridge of high pressure weakens and moves eastward as the next system forms up over the Eastern Great Basin and Four Corners area drawing rich moisture fields from the Pacific/Baja California region. An upper level cutoff Low gets entrained into the flow and the Low pressure over four corners will intensify. By Saturday morning large moisture fields are in place over Western Slope of CO. Saturday afternoon as the Low pressure moves eastward over Southern CO, an upslope component will develop bringing light showers of rain/snow mix across eastern CO and SW Nebraska through late Saturday night. Light snow accumulation around 2-3 inches could be expected with this shower activity throughout the day. By Sunday morning the Low pressure system will eject eastward over the Midwest leaving showers possible across CO and NE. Sunday midday looks to be clearing out with high pressure beginning to build over the area. Temperatures for the weekend across eastern CO and southwest NE will struggle to get above freezing with the exception of daytime heating.