Canadian air that has been hovering over the Upper Midwest this past week is making a push into the Northeast this weekend.
Cooler and less humid conditions are in store from the Great Lakes to New England and the northern mid-Atlantic.
With lower humidity, it should be more comfortable working outdoors this weekend, even where temperatures rebound into the 80s along much of the I-95 corridor from Washington, D.C. to Philadelphia, New York City and Boston.
Temperatures are forecast to dip into the 40s over the mountains in the region at night.
Lows will be in the upper 60s to near 70 in the major cities near the mid-Atlantic coast.
Farther south, the advance of cooler and less humid air will slow to a crawl. Showers and thunderstorms will frequent areas from Tennessee to North Carolina, with southern Virginia and southern West Virginia on the bubble between the dry air to the north and flooding downpours to the south for a time this weekend.