Spring fever alert issued for big part of U.S.

March 7 (UPI) -- Following a burst of chilly air that raced from the Midwest on Friday into the Northeast on Saturday with snow showers adding to the wintry feel for some areas, weather whiplash will allow springlike warmth to build from the Great Plains to the Eastern Seaboard.

Some people may be able to leave the jacket at home and a few may even be able to break out the short sleeves for a day or two in the upcoming pattern.

For those communities devastated by tornadoes in Tennessee from early this week, or others in the South who have dealt with recent flooding, the break of dry, tranquil weather will be more than welcomed.

A quick southward dip in the jet stream will be followed by a rapid northward bulge, just like a giant atmospheric whip. In most cases, the warmup will be accompanied by at least partial sunshine.

Temperatures will respond in a rapid, positive way. Even though most record highs this time of the year are likely to be out of reach during the warmup, temperatures will still surge to well-above-average levels.

Highs and lows are forecast to trend upward by 15 degrees to 30 degrees Fahrenheit in 24 hours, with the Heartland first in line to experience the warmup.

In Minneapolis, highs near 40 on Friday will be swapped with a high in the middle 50s on Saturday and then the middle 60s on Sunday.

Temperatures could make a run into the lower 70s over part of the Ohio Valley by Sunday. Even Chicago and Detroit can expect temperatures to reach the 60s on Sunday.

Farther east, a cold start to the weekend will be followed by a mild finish. Spring fever alerts may have to be issued for Monday and Tuesday, when the bulk of the warmth is in store.

Boston and New York City can expect highs in the 60s on Monday, and temperatures have a chance of reaching 70 in Philadelphia and may reach the middle 70s in Richmond, Va.

Given that such a vast stretch of the area from the Plains to the mid-Atlantic and southern New England has no snow on the ground, there is the potential for this warmup to overachieve and exceed forecast high temperatures by several degrees, according to AccuWeather meteorologists.

March has already started on a warm note across the Midwest and Northeast. The average temperature for the first four days of March is 9 degrees above normal in Chicago and nearly 9 degrees above normal in New York City. Detroit's temperature so far this month is more than 7 degrees above average, and Philadelphia's is more than 6 degrees above normal.

Indications are that a stiff breeze will accompany the peak of the upcoming warmth. Even though the breeze will help the atmosphere warm up over the eastern two-thirds of the nation, the breeze may add some coolness to the air at the local level, especially in the shade and where the breeze blows off a chilly lake, river or bay.

"A breeze off the chilly Hudson River may prevent midtown Manhattan from hitting 70 on Monday," AccuWeather senior meteorologist Dave Dombek said.

That breeze will be amplified as air must rush in between the tall buildings of New York City and the other major urban centers in the Midwest and the Northeast.

The wind direction may keep the eastern shores of the Chesapeake and Delaware bays rather cool.

"A breeze from the Potomac River may keep the tidal basin cool as well around Washington, D.C.," Dombek said.

Since official weather measurements for the nation's capital are kept at Reagan National Airport, which sits west of the Potomac, a high in the 70s is likely to be recorded.

"However, with winds forecast to blow from the west and southwest, the warmup should be felt all the way to most Atlantic beaches, instead of a chilly sea breeze kicking in," Dombek added.

Officials expect the peak of the cherry blossoms at the National Mall in Washington, D.C., to be in late March this year.

The average peak of the blossoms in the nation's capital is April 4. The warmth early next week may cause the peak bloom to occur a couple of days earlier than current estimates.

A weak storm with rain showers will mark the end of the warmth as it progresses eastward.

The cooldown will progress from the Plains on Monday to much of the Midwest on Tuesday and the Northeast on Wednesday.

More ups and downs in temperature are in store for the rest of the month. And, for portions of the Midwest and Northeast, it could get cold enough for snow again at some point over the next few weeks.