The beginning of the week in North America will bring warmer temperatures to the east coast, up to 20°C/68°F (in Florida 25°C/77°F). At the weekend an anticyclone will move above the north of the east coast and it will go south, which means colder temperatures (around 0°C/32°F except Florida). The cold will reach its maximum strength next week.
A similar weather is forecasted above the west coast. The cyclones that bring warm air around 10°C/50°F will be followed by an anticyclone, shortly cooling the west coast to 5°C/41°F at the beginning of the next week.