A major shift in the weather pattern will drive a blast of cool air southeastward from Canada across the Plains, Midwest, East and South into the weekend.
The blast of air from the Canada Prairies will drive temperatures and humidity levels down all the way to Texas and eventually much of the Atlantic Seaboard.
Temperatures may struggle to top 70 around Chicago both days of the weekend.
As the cooler air blasts across the warm waters of the Great Lakes, waterspouts are likely to spin up this weekend.
In Texas, the 100-degree heat from much of this summer will be replaced by highs in the 80s with much lower humidity in such cities as Dallas, San Angelo and Houston.
In the central and northern Appalachians, in the wake of the front which marks the leading edge of cooler air, the coolest spots could have highs near 60 on Sunday.
In the Deep South, for the folks who have been enduring tropical heat and humidity this week while cleaning up after Isaac, highs in the 80s with low humidity and sunshine will settle in later this weekend into next week.
While the magnitude of cooling will be less pronounced in much of the East's I-95 corridor, humidity levels will be shaved substantially and highs will be in the 70s by early next week from Boston to New York City and Washington, D.C.
The blast of cooler air and refreshing humidity will be preceded by rounds of showers and thunderstorms, which can lead to flash flooding and localized severe weather.
The downpours and severe weather will hit portions of the Midwest Friday then the Deep South and Atlantic coast into the weekend.
In addition, folks in portions of Florida may have to deal with a weak tropical system, such as a tropical depression or tropical storm and its torrential downpours this weekend. The feature could come about of a cluster of thunderstorms over the northern Gulf of Mexico, which are part of the old remains of Isaac.
As cooler air drives into the eastern U.S. this weekend, a compensating northerly flow over the Atlantic Ocean may help drive Hurricane Leslie into Atlantic Canada early next week.
Dry, chilly weather will remain across the Chicago area through the weekend as travelers begin their trek home from Thanksgiving destinations.
Atlanta will see temperatures climb through the weekend and into the new week.
The San Francisco Bay area will see a few storm systems bring periods of rain to the area throughout the weekend before heavier rainfall moves in early in the new week.
While sunshine and pleasant conditions will hold through the weekend in the Los Angeles area, much needed rain will return to the drought-stricken region early in the new week.
The Detroit metro area will face a mix of snow and rain over the weekend as travelers head home after holiday festivities.
Mother Nature delivered a blast of fresh powder as a pre-Thanksgiving snowstorm struck the East, much to the delight of holiday skiers.
Havre, MT (1896)
Minus 51 degrees.
New England (1945)
Severe "nor'easter" in New England - winds in Boston averaged 40.5 mph over a 24-hour period. The rain changed to snow which accumulated to 16 inches in interior New England. Thirty-tree deaths were attributed to the storm.
November 1972 was one of the wettest on record for the Northeastern U.S. As of the 27th, NYC had its wettest November ever with 11.36 inches. This broke the old record of 9.97 inches. Binghamton, NY, had a monthly total of 7.11 inches -- the wettest November in the 75-year history of record keeping at Broome County Airport. Binghamton also had 19.4 inches of snow -- exactly a foot above normal.