A major change to the persistent mild fall weather of late will come by the end of the week. The timing and track of this next system is still uncertain, which will impact precipitation type and amounts.
A southward plunge of the jet stream will surge into the West around the middle of the week, before sweeping eastward into the Plains states. Ahead of that feature, an area of low pressure will form at the surface over the Plains, then intensify as it tracks into the northern Great Lakes late this week.
Cold air will be drawn southward out of Canada on the backside of this low-pressure system.This Canadian air will be sufficiently cold to dump snowfall along its journey in parts of the northern Plains and Great Lakes, in addition to blanketing the mountain West with some sorely-needed early-season snowfall.
While most of the snow will miss the state, light snow may be possible by Friday night across northeast Nebraska, northwest and northern Iowa.
Winds will also be strong with this system, which may require a wind advisory. Temperatures will be some of the coldest we have seen thus far this season. Lows Friday night will be in the 20’s, with highs over the weekend in the 30’s to 40’s. Since there still remains a lot of uncertainty, continue to follow the latest updates our Facebook and Twitter page, and at IowaChase.com.