The eastern U.S. is heating up, with temperatures rocketing into the 80s through the weekend for major cities. 

Although meteorological summer does not officially start until June 1, highs in New York, the District of Columbia, Philadelphia and Boston are all forecast to surpass 80 degrees by the end of the week. 

DANGEROUS FLOODING, STORMS THREATEN GULF COAST

AccuWeather reported Tuesday that some high temperatures would even extend to 90 degrees this week for the first time this year, though Virginia and the Southeast have experienced 90-degree readings already. 

The forecaster said that May 22 would be the first 90-degree day for Charlotte, N.C., May 24 would be the first for Philadelphia and May 31 would be the first for Atlanta. which has come as close as 86 degrees in April.

FILE - In this Sunday, May 2, 2021 file photo, patrons seated at outdoor tables at a restaurant converse and dine in Boston. (AP Photo/Steven Senne, File)

FILE - In this Sunday, May 2, 2021 file photo, patrons seated at outdoor tables at a restaurant converse and dine in Boston. (AP Photo/Steven Senne, File)

The predictions for average first dates for 90-degree temperature readings are based on more than 30 years of data from 1991 to 2020, according to AccuWeather.

It also said that temperatures may even approach 100 degrees in Georgia and South Carolina.

However, while temperatures will begin to trend upward, even as north as Maine, humidity levels are expected to rise as well.

NATIONAL WEATHER FORECAST: STORM SYSTEM LINGERING OVER CENTRAL, SOUTHERN US

This trend will be the case in southern states as well, including around the Gulf Coast where severe storms and floods have threatened communities over the last few weeks. 

The National Weather Service's (NWS) Weather Prediction Center said Tuesday that there would be a Moderate Risk of excessive rainfall over the Central Gulf Coast to the Southern Plains through Thursday in addition to a Slight Risk of severe thunderstorms over the Southern Plains through Wednesday morning.

The agency said over the Southern and Central Plains and Mississippi Valley thunderstorms and showers would continue to develop, causing more hazardous flooding and more rain is set to sweep parts of the Midwest, Great Lakes, Northern New England and the east coast of Florida later in the week.

CLICK HERE FOR THE FOX NEWS APP

To the west, a front from the Rockies to Northern California will move eastward and by Thursday rain and highest elevation snow will develop over parts of the Pacific Northwest and Rockies.