Police agencies and the weatherman agree: Stay home Saturday. The accident you avoid may be your own.

Not only is a lot more snow being dumped on the Wasatch Front, but canyon winds are predicted Saturday and Sunday - which could turn cars into sailboats along Utah's already snowpacked highways and reduce visibility to the vanishing point.Utahns, battered by several days of heavy, record-setting snows, traffic tie-ups and freezing winds, braced for more of the same after being told that "If we can survive three more days of this horrid weather, things should start improving Tuesday."

That came from William J. Alder, meteorologist in charge of the National Weather Service's Salt Lake office as he issued yet another winter storm warning Friday.

Alder said more snow, colder temperatures and high winds will blast the Wasatch Front and much of northern Utah Saturday, Sunday and possibly Monday.

Alaskan air has dumped snow, freezing rain and sleet on much of the nation and yanked the bottom out of wind-chill readings. Nationwide, schools have been closed and roads have become more fit for ice skating runs than traffic.

In Utah, which has escaped the severe freezing that hit its northern neighbors, snowfall records tumbled. Utah County registered the most snowfall in the state Friday as the official weather station at Brigham Young University recorded 17 inches from 1 p.m. Thursday through 1 p.m. Friday - the most snow ever recorded at any Provo weather site in any 24-hour period.

Utah police agencies Friday reported dozens of weather-related accidents. Authorities are still investigating a Friday morning accident in which a pregnant woman and her unborn child were killed. Connie Solomon-sen, 25, 3231 W. 6960 South, who was due to deliver a baby Friday, crashed on eastbound I-215 near 59th South, authorities said.

Alder said he expects canyon winds Saturday morning along the Wasatch Front and possibly stronger winds Sunday morning. Temperatures Saturday in northern Utah are expected to tiptoe into the mid-20s. Highs Sunday should be in the upper teens. Lows Saturday should be in the midteens and should drop Sunday to about 10 degrees.

"I expect about 4 to 6 inches of snow in the valleys and a foot or more in the mountains over the weekend," Alder said.

Alder said ski resorts had plenty of new snow, even without Friday night's storm. "In 24 hours, Alta had 25 inches; Brighton, 22; Deer Valley, 21; Snowbird, 21; Solitude, 16; and Sundance, 22."

Record temperatures were set or tied at Billings, Mont., 26 below zero; Casper, Wyo., 29 below; Great Falls, Mont., 35 below; Sheridan, Wyo., 32 below; and Spencer, Iowa, 21 below.

Wind chills sank to 60 to 80 below zero across parts of Minnesota, Iowa, the Dakotas, Nebraska, Wyoming and Montana. Missoula, Mont., had a wind chill temperature of 85 below zero; Rapid City, S.D., had an 80-below wind chill; and Mason City, Iowa, had a wind chill reading of 78 below zero.

Authorities in the Seattle, Wash., area said four youths died from injuries in separate sledding accidents. One was the King County prosecutor's daughter, who died of head injuries when the inner tube she was riding on ran into a parked car.

*****

Can't blame greenhouse

Last year's global average temperature was the warmest ot the century, and the six warmest years of the century all have occurred in this decade, a study by Britain's Meteorological Office reported. Officials said it was too early to conclusively blame the greenhouse effect, in which heat from the sun is trapped in the atmosphere by gases acting like the glass walls in a greenhouse. It could take 20 years of temperature rises before the greenhouse effect could be detectedwith much certainty.