A massive storm system pushed eastward over the nation yesterday, dumping new snow on western Maryland and Virginia and threatening the already waterlogged Washington area last night with its first substantial snow of the season.

Heavy seas continued to batter craft along the east coast as well. At least four ships foundered or sank in Chesapeake Bay and along the Maryland-Virginia-North Carolina shoreline since Sunday, the U.S. Coast Guard reported yesterday Crews from three of the craft - all tug boats towing barges - were rescued. One coast guardsman was injured during the rescue operations.

A 685-foot tanker carrying 9 million gallons of fuel oil sprang a leak 90 miles east of Cape henry, Va., yesterday and was reportedly limping into Hampton Roads, Va., last night for repairs.

High seas also battered resort centers along the Delmarva Peninsula, causing extensive beach erosion at Ocean City, Md., and damaging some buildings there. One oceanside condominium building was hit by waves that poured water into its elevator shaft and knocked out the building's power. Marinas in the area also have suffered some damage, according to the Coast Guard.

National Weather Service forecasters painted a generally chaotic meterological scene for the nation, with snow, frigid temperatures and howling winds in the Midwest and unseasonable heat in parts of the South.

The brunt of the storm system currently pelting the Midwest and upper Plains states with snow is expected to pass noth of the washington area, leaving this area relatively unscathed.

The snow expected last night may be followed by more flurries tonight and possibly Thursday, weather service forecasters said, but with no substantial additional accumulations.

The outlook for the Christmas weekend calls for clearing and generally fair conditions. it will be cold, with lows in the teens and 20s Friday and Saturday night and mostly in the 30s during the day. Christmas Day should be somewhat milder with temperatures creeping up to the 40s.

Fresh snow hit counties in western Maryland and Virginia yesterday but slacked off in the afternoon. Maryland State Police canceled a snow emergency plan for Garrett and Allegany counties at 2:30 p.m.

The weather service at midafternoon reported snow accumulations of 2 to 2 1/2 inches in Harrisonburg, Va., Rappahannock County, Va., Frederick, Md., and the eastern panhandle of West Virginia. Cumberland, Md., reported 1 inch of snow.

Along the Atlantic Coast, a tugboat and barge ran aground at Ocean City Sunday and was abandoned. Another tug sank at the mouth of the Rappahannock River in Chesapeake Bay, and a third tug was cut loose from its barge off Cape Hatteras, N.C., and its nine crew members airlifted to safety by a Coast Guard helicopter.

In the Ocean City incident, the 85-foot tug Pauline Holmes with a 214-foot barge in tow ran aground off 94th Street. Coast Guard and Ocean City rescue workers floated a line out to the foundering tug from the beach, and the four crew members came ashore holding to the line, according to a Coast Guard spokesman.

One coast guardsman suffered several broken ribs in the rescue effort. The tug and barge both broke apart shortly after the rescue. The barge contained only water ballast and some sludge, the Coast Guard said.

Eight crew members were rescued from the 91-foot tug Carolina just before it sank Monday in 25 feet of water at the mouth of the Rappahannock River. A barge it was hauling broke loose but was taken into tow by two nearby commercial ships.

The 110-foot tug Texas developed engine trouble Monday off Cape Hatteras as it was towing a 414-foot barge containing 13 1/2 tons of carbon tetra-chloride, according to the Coast Guard.

After losing control of the tug in heavy seas, the nine crew members climbed onto the barge, cut the tug loose and waited until they were airlifted by the Coast Guard to Elizabeth City, N.C. Search craft were still looking for the abandoned tug last nigh. The Coast Guard cutter Cherokee was standing by to take the barge into tow as soon as the rough seas subside, the Coast Guard said.

The Greek-owned Aegis President, a 685-foot tanker with 9 million gallons of No 6 fuel oil, sprang a leak and began taking on water off Cape Henry Monday. With a Coast Guard cutter escort, it was reported heading into Hamption Roads last night for repairs.