Iowa Weather Report December 15th 2014: Joy To World, Colder Air is Coming

THE WEEK AHEAD: Rain will be the main story today across the state with some embedded thunder possible as well. Some of the rain will mix with some sleet or snow in our northwestern counties by the afternoon hours as the cold air filters in from that direction. Highs today will be in the 30s northwest through the lower and middle 50s southeast. These temperatures will be falling through the afternoon into the evening hours as the cold air moves in. This will change over the precipitation to a wintry mix and or snow before ending. Any accumulating snow will likely be over the northwestern quarter of the state where an inch or two is possible. Skies will be slow to clear Tuesday as the system departs with readings likely being in the 20s and 30s for highs. This will be the case throughout the rest of the week as readings will be near seasonal levels for the middle of December. Another system will skirt the state Friday into the first part of Saturday. This may bring some snow with some wintry mix possible during the daylight hours in our southern and southeastern counties of the state. It’s still too early to determine any snowfall accumulations at this time as the track has been wavering north and south. We should have a better handle on this in the coming days. Sunday will keep the seasonal streak going with partly to mostly sunny skies at that time.

GOING FARTHER OUT: The GFS has a cold look at the extended period with a system moving through around the 23rd that may bring us some snow at that time. This looks to merge with another system off to our east which would take the low pressure center up north to Hudson Bay and park itself for the rest of the period (being replaced by another low pressure center toward the end of the period). This would bring much colder temperatures to the state at that time, similar to what we had in November, if not colder than that. This is dependent on any snow pack we have and other factors. What it does show that the warm weather from the last few days may be the last we see for quite some time.