As a cold spell continued its rigid hold on much of the eastern United States on Tuesday, farmers in central and southern Florida were bracing for freezing temperatures overnight that could damage orange, strawberry and tomato crops.

The frigid weather was also blamed for four deaths in Tennessee, and has produced record snowfalls in New England.

In Nashville, police said the body of an 81-year-old man was found in the front yard of his Oakes Drive home on Monday morning. The man's family told police that he suffered from Alzheimer's disease, and that they believe he walked out of his home in the night dressed in his bathrobe.

The deep freeze, brought on by surges of high-pressure arctic air masses moving down from northwestern Canada and the northern Great Prairies, has been lingering since the weekend in many places that are not accustomed to subfreezing weather, meteorologists said.

Schools were closed in Arkansas and parts of West Virginia, where up to 8 inches of snow has fallen in the last few days. In Burlington, Vt., a storm dumped more than 33 inches of snow from Saturday through Sunday, breaking a record set in 1969 for the largest snowfall there, according to statistics kept by the National Weather Service."This cold snap is lasting longer than normal," said Rick Davis, a meteorologist with the National Weather Service in Tampa, Fla., where the mercury can fall below freezing several times a year but usually rebounds by the next day. "We've had it the last three or four days, and it will last for the better part of the week and this coming weekend, so we're going to have a solid 7-to-10-day stretch of lower-than-normal temperatures."

He said the conditions were particularly problematic to farmers, especially in central and southern Florida, where January is the middle of the growing season for strawberries and citrus fruit.

"This is the anxious time of year," said Andrew Meadows, director of communications for Florida Citrus Mutual, a growers' association. "But it's part of being in agriculture. It's the whims of Mother Nature."

So worried are farmers about the effects of a prolonged freeze that Charles Bronson, the state agricultural commissioner, asked Gov. Charlie Crist on Tuesday to lift a weight limit on trucks that haul produce.

"That way farmers can load up the crops they're already harvested and get them out of harm's way," said Terence McElroy, press secretary for the Florida Department of Agriculture and Consumer Services. "This thing isn't over yet, and we don't know where we'll be at the end of it."

He said agriculture, the state's second biggest industry after tourism, has an economic impact in excess of $100 billion a year.

Mr. Meadows said that crop damage occurs when the temperature stays at 28 degrees Fahrenheit or lower for at least four hours. Readings as low as 27 have been seen the last few nights, he said, but generally just before daybreak, and only for an hour or so before the rising sun heated things up again. "There were no reports of damage" so far, he said.

But a forecast of a more lingering frost Tuesday night prompted farmers in many parts of Florida to take precautions to protect their crops, he said. One favored method may seem paradoxical to laymen: activating microsprinklers when the temperature is below freezing to make ice that protects a fruit-bearing plant or tree from the frigid air.

"If you were paying attention in your high school physics class, you may know that the formation of ice creates heat," he said, referring to an effect that scientists call the heat of fusion. "That will protect the tree or that portion of the tree - the bottom and the trunk - from freezing."

Mr. Meadow said there were some freezing spells last winter that caused damage in some pockets of Florida, but nothing like the big freeze of 1989, when frigid temperatures for several days around Christmastime caused huge crop losses throughout the state. Many growers moved their operations farther to the south after that winter.