If you don't already have that pair of thermal underwear, forget it. Your clothing store probably is out of stock.

If you haven't already gotten the boots and heavy clothing for the kids, it'll be tough sledding because most stores have almost nothing left in cold-weather gear for children.

Frigid temperatures have sent Washington area customers scrambling back to stores for anything to keep themselves, their families and their homes warm.

Shivering consumers have practically stripped the shelves of many large department and drug stores of everything from electric heaters to blankets to ear muffs.

One of the hottest selling items during the cold spell has been processed logs for fireplaces.

Ben B. Ruby, district sales promotion manager for Montgomery Ward, reported that area stores sold 10,000 packages of logs during the first two days of last week. Last year that was the total sold during the entire winter, he said.

David Eisenberg, general merchandising manager for Peoples Drug stores, said that so far this season, 62,000 cases of the compressed wood logs have been sold compared to 33,000 cases for all of last winter.

Montgomery Ward and Hechinger's reported that their stores were out of electric and gas heaters and Peoples' supplies are very low Eisemberg said.

Space heater manufactures stopped making the small heating devices in mid-November, several store representatives said, and convarted to making electric fans for spring and summer.

"There has been an unusual demand for charcoal and sterno," Eisenberg reported.In addition he said the drug store chain had purchased 1,000 extra nonelectric blankets to meet demand.

"Blankets were selling like they were going out of style after the Jan. 5 snow," said Joanne Steller of Woodward and Lothrop. A Drug Fair representative said that chain had sold out of blankets in most of its stores.

"We're completely out of outerwear, heavy outerwear for men and women," such as winter coats and parkas, Montgomery Ward's Ruby siad. "If you came in one of our stores for a heavy winter coat we wouldn't have it to give you," he said.

"We went through 77 per cent of our entire winter stock for children between Jan. 5 and Jan. 13." That supply had been expected to last till March, Mrs. Steller said.

"We sold out of ear muffs, thermal underwear and rubber boots for men" shortly after the early January snow, she said.

Woodies has no more knit cap and scarf sets for women and "very small quantities of gloves," she said.

A spokesperson for Hecht's said that the store was low on sweaters, gloves and blankets and "overall there is an increase of sales in items that keep people warm."

A representative of Sears said that the chain is supplying most of its stores almost daily to keep batteries, anti freeze, snow tires and ice scrappers on the shelves.

"We've sold practically every battery we have. We're selling them as fast as we get them in," said Ruby of Montgomery Ward.

Antifreeze sales present a mixed picture. While Ruby reported no real increase in sales, Eisenberg at Peoples said last year the chain sold 150,000 gallons during the winter. "This year we've already passed a quarter-million gallons," he said.

A representative of Hechinger'sa also reported increased sales of storm windows and doors and insultation.