7:05 p.m. EST February 18, 2015  A ferocious blast of bitterly cold air straight from Siberia was roaring through the eastern and southern USA on Wednesday, dropping temperatures to historically low readings as far south as Florida.

"This could be some of the coldest weather since the mid-1990s for parts of the Southeast U.S., Mid-Atlantic and central Appalachians," said meteorologist David Hambrick of the National Weather Service.

Highs on Thursday and Friday will struggle to get out of the teens in many of those areas, and overnight lows could reach zero degrees or even lower in spots, Hambrick said. Dozens of records will be threatened as temperatures plummet to as much as 25 to 30 degrees below normal for this time of year, the weather service warned.

Low temperatures Thursday morning are forecast to be below zero in Nashville, Cincinnati and St. Louis, and in the teens in Atlanta, Birmingham, Ala., and Jackson, Miss.

Wind chill advisories and warnings were in effect Wednesday afternoon all the way from International Falls, Minn., to Boca Raton, Fla.

Floridians will even experience a taste of the arctic chill, with temperatures dipping to the lower 30s in cities such as Orlando, Melbourne and Daytona Beach, according to AccuWeather.

The National Weather Service warned "the overall weather pattern through the end of the week will ... (keep) the central and eastern parts of the U.S. much colder than normal."

Across the nation, this winter has actually been one of the mildest on record due to warmth out West. That comes as little solace to Nashville Mayor Karl Dean.

In Tennessee, hit hard by an ice storm that locked up highways across much of the state, a winter weather advisory forecast potential record-low temperatures to minus-4 degrees in coming days. Temperatures were not forecast to reach above freezing until Saturday, the National Weather Service reported.

"It's going to be a long couple of weeks," Nashville Mayor Karl Dean said. "We continue to deal with below-freezing temperatures."

In Louisville, the weather service issued a wind chill advisory beginning at 4 p.m. Wednesday through 7 p.m. Thursday with gusty, arctic winds of over 20 mph. Wednesday's high is expected to top out at 19 degrees with a low of minus-9 degrees and a wind chill as low as minus-21 degrees. Thursday's forecast high — 6 degrees.

In Washington, D.C., WUSA-TV meteorologist Topper Shutt warned temperatures won't make it out of the teens Thursday, and Thursday night's low temperature could be the coldest "since the 1990s, with quite a few suburbs below zero air temperatures."

The weather service issued a freeze watch for the Central Florida coast.

"Right now for Thursday we're looking around the mid- to upper 30s," said Bob Wimmer, a meteorologist with the National Weather Service in Melbourne, Fla. "We'll be flirting with near-freezing temperatures, and with the winds at 10 mph, it will feel even colder."

Thursday morning's temperatures could feel as cold as 25 to 30 degrees by sunrise with winds at 10 to 15 mph, he said.

But Florida, unlike much of the nation, can expect a serious warmup in a few days. Saturday's forecast high for Melbourne is 71 degrees. Sunday: 77.

New England, which has been socked with up to 8 feet of snow so are this winter, won't be so lucky. Parts of Maine and New Hampshire could get a foot of snow Friday.

In Eastport, Maine, the current snow depth -- not the amount that's fallen this winter but the actual amount on the ground -- is an "amazing" 78 inches, the weather service said. That's six 1/2 feet.

The weather service has posted winter storm watches for all of Maine and northern New Hampshire. "Some locations where the heavy snowbands persist the longest will likely tally over a foot of new snow," The Weather Channel warns.

Contributing: Tony Gonzalez, The (Nashville) Tennessean; The (Louisville) Courier-Journal; J.D. Gallop, Florida Today.