The fall season 2021 will start with a significant cold blast across part of the United States.
By Monday evening a cold front will already reach southern Colorado and central Kansas, while hot temperatures will remain farther south and east. Tuesday brings a much colder air mass farther south across the Plains, temperatures at the 850 mbar level will be about 6-10°C lower than normal for this period.With the surface front surging farther south and east. By Tuesday afternoon, the front will be extended from Illinois across the central Mississippi Valley towards northern Texas and continue southeast.
The cold air mass will have barely any reason to stop its progress far towards the south until it reaches the Gulf Coast on Wednesday. The coldest air mass spreads into the central parts of the Contiguous United States, spreading also towards the east. A cold air mass is forecast to gradually spread further east-southeast on Thursday and Friday, maintaining into the weekend. Resulting in cool fall season weather for the East Coast and the Southeast US.Some hints are that another intrusion might follow from Canada over the weekend, extending the fall season temperatures into Monday and Tuesday.