Arctic air pouring into the Pacific Northwest and the Plains will also dip as far south of Los Angeles.
It won't be as bone-chilling in Los Angeles as it will be in the Plains, but nighttime temperatures will be in the low 40s through Sunday.
There could be problems inland with a frost and freeze through Thursday night with temperatures in some areas dipping well down into the 20s.
After the new week begins with stormy weather, the Cleveland area will see temperatures reminiscent of September move in midweek.
Dallas will see continued periods of heat and dry weather before severe storms bring cooler temperatures midweek.
The first part of this week will feel more like September than the middle of July, typically the hottest time of year, throughout the Midwest.
The hot weather seen across the Northwest over the weekend will carry over into the new week, continuing the risk of heat-related illness.
The Northeast and mid-Atlantic will be faced with severe thunderstorms and flooding downpours through at least Tuesday before the new week ends on a more refreshing note.
Walker, IA (1992)
3.5 inches of rain in just one hour caused stream and river flooding.
New Jersey, NY (1895)
Cherry Hill Tornado in North Jersey caused $50,000 damage; funnel then descended at New York City in Harlem and Woodhaven, where one was killed; ended as a waterspout in Jamaica Bay; New York City damage totalled $43,000. Note: This is not the Cherry Hill in South Jersey.
Mississippi Valley & Great Lakes (1936)
Searing heat across the Upper Mississippi Valley and the Great Lakes: Evansville, IN 107 degrees Alpena, MI 104 degrees Grand Rapids, MI 108 degrees St. Cloud, MN 107 degrees Wisconsin Dells, WI 114 degrees; all-time record. Green Bay, WI 104 degrees Fort Francis, ONT. 108 degrees; highest ever in Ontario Province. Mio, MI 112 degrees, all-time high in state.