Ultra marathon swimmer Skip Storch looks out on the Hudson River in Piermont, N.Y. Storch, who posed for the photo Friday, will try to break the unassisted swim record of 85.5 miles in 33 hours and 30 minutes by circling Manhattan at least three times, possibly four, starting Wednesday.

New York ? Skip Storch was swimming down the East River while lightning flashed and hail pelted his head. As he came past Roosevelt Island and drew near the United Nations, the skies parted and the sun broke through. He looked up and noticed a fisherman on shore.

“Any luck?” Storch called out.

The fisherman just stared at him.

“Now I’ve seen it all,” he said.

Then he poured out the beverage he had in a brown paper bag at his side, threw the bottle into the river and left.

Who knows how many more urban anglers are in for a surprise Wednesday, when Storch plans to circle Manhattan three times?

The 50-year-old, who has been hooked on long-distance swims since he was 10, is doing the marathon swim to raise money for the sarcoidosis treatment program at Mount Sinai Hospital.

Many New Yorkers – Storch among them – have contracted the disease since the terrorist attacks of Sept. 11 sent clouds of contaminated dust into the air around the city.

“I’ve always wanted to do this swim. Since the ’80s, I’ve always romanced the idea,” Storch said.

Sarcoidosis is an inflammation that produces tiny clumps of cells in various organs that can eventually affect their functioning.

Recently, the city medical examiner ruled that a woman exposed to the dust on Sept. 11 who died of sarcoidosis in February 2002 was a victim of the attacks.

“Ever since, people have been getting it,” Storch said. “Some of them have had such horrible degrees of it.”

As the only person ever to swim the full length of the East River, from Long Island Sound to the tip of Manhattan, Storch knows these waters well. He circled Manhattan once, in 1987, and he also holds four records recognized by the International Marathon Swimming Hall of Fame – one for his the East River swim and three others for various Hudson River swims.

And when he’s not paddling around New York’s waters, he runs a tackle and fly shop in Rockland County, just a short swim – by his standards – upstream from the city.

So if anybody is brave enough to spend a day and a half or more marinating in the runoff from a metropolitan area of 18 million people, it’s him.

Storch’s weakened immune system is just one of the dangers he faces in the water. If it rains before or during his swim, overflowing sewers will fill the Hudson with fecal coliform bacteria.

Rain also will lower the temperature of the water. Although it’s still comfortable enough for a quick dip, even a relatively warm 77 degrees Fahrenheit can cause hypothermia if you’re in it too long.

The record for the 851â2-mile trip is 33 hours, 30 minutes, set by Stacy Chanin in 1984, when she was 23.

To break the record, Storch is looking at a solid day and then some of immersion. And he’ll be wearing only a bathing suit, goggles and cap.

“This is why I’m doing this swim also,” Storch said. “To illustrate the difference between an assisted swim and a non-assisted swim.”

To ward off hypothermia, Storch has grown a layer of fat he expects to melt off in the water. When he stops to take food or drink from a support boat, he’ll make sure what he takes in is already heated to near body temperature, to minimize the cooling effect as his body reroutes blood to his digestive tract.

A bigger danger than E. coli or hypothermia, however, are the swirling currents he’ll encounter every stroke of the way.

The Hudson River is an estuary, subject to tides much farther upstream than the city. Storch has it planned so that both the current and the stronger-than-usual ebb tide late next week will whisk him down the West Side to the Battery, where he’ll tread water until the flood tide – which moves at a brisk 4 knots or so – can help bring him up the East River, which is actually a strait between Manhattan and Long Island.

All that water being pushed and pulled in and out of the harbor can make for some treacherous currents. Storch said he’s felt currents beneath the surface tugging at him, and seen whirlpools in the East River near the Hell Gate, which he’ll skirt on each lap.

On his flotilla of boats, the flagship of which will be a 75-footer called The Ninth Wonder, will be divers and a registered nurse in case anything should go wrong.

Once Storch completes his first lap of around 28 miles, he plans to tread water until the currents subside and he can set out again on lap 2, during which a lunar eclipse will take place shortly before 6 a.m.

Storch will need to finish before 9:30 p.m. on Thursday night to break the record.

Of course, that assumes he doesn’t decide to go for a fourth lap. The man does love to swim.

“It’s just what I know,” Storch said. “These swims, I’m so alive when I do them, It keeps me going. It’s not an addiction, it’s a way of life.”