Rollie Chapple figures that his dad's bad back and an untrustworthy outboard motor saved his life that day. At just 17 years old, Rollie was already an 11-year veteran of the Mississippi River bottoms and the whims of weather. But he and his dad, Lawrence, a true river rat tutor, had never seen anything like this before.

Father and son were on a three-day duck hunt. It stretched into Monday because school was out for the holiday. It was Nov. 11, 1940. Armistice Day.

The Chapples made the 60-mile trip on Friday evening from their home near Hixton, Wis., to a log cabin Lawrence had built on the shores of the river near Buffalo City. They were 14 miles north of Winona on the Wisconsin side. The weather Saturday and Sunday was unseasonably warm and misty. That was about to change -- big-time.

"One of the great myths about Armistice Day 1940 is that the duck hunting was so good people stayed out on the river when they shouldn't have," said Rollie, now 86 and living in Eden Prairie. "The truth of the matter is, hunting was only fair, at least in the Buffalo Bottoms. The great majority of the ducks had sensed the coming storm and flown south."

About noon Monday, the elder Chapple waded over to the 14-foot Shell Lake cedar strip boat where Rollie was hunting. It was still warm. A light southeast wind had died.

"What do you think, son? Should we wrap it up?"

"Whatever you think, Dad."

"My back is aching like a storm is coming," Lawrence said. "Let's get out of here."

But in the few minutes it took to gather their ducks, pack their gear and make their way through the backwater islands for the run across the open water Mississippi channel to their cabin, the weather had changed dramatically.

"The wind came in like a summer squall," Rollie said, "from calm to furious in a matter of minutes." Lawrence beached the boat on a steep sandbar created by the Corp of Engineers when it had dredged out a navigable channel. He studied the angry waves in the quarter-mile of open water separating them from the cabin. The wind was clipping the tops off the white caps.

Lawrence noted the northwest wind had a mile or more reach right down the channel. He also worried about their cantankerous outboard motor. "I can still see my dad bracing himself against the wind with an oar while he studied the river," Rollie said.

"And now snow was whipping down the river in horizontal sheets," he added.

When his dad slid back down the sandbank to the boat, he announced: "We'll hunker down out here. Help me drag the boat up and over this bank." The Chapples were unaware that only 6 miles south of them in Fountain City, Wis., other duck hunters who had decided not to hunker down were drowning or freezing to death trying to get off the river.

Using the lee side of the sand ridge for protection from the now-shrieking wind, Lawrence and Rollie turned the boat on its side. Then, with an ax that was always part of their duck hunting equipment cache, they cut forked branches to hold the port-side gunnel up enough for them to crawl under the boat. Then Lawrence directed his son to begin collecting firewood. With great difficulty they started a fire near enough the boat to absorb some heat.

"We were never really uncomfortable," said Rollie, "because we each had a duffel bag with extra clothing and plenty of sandwiches and apples my mom had sent with us. My dad had been burned before by weather. So, if anything, we were overprepared."

When daylight broke on Nov. 12, the father and son emerged from the snowdrift surrounding their boat shelter and were stunned by what they saw and felt. The temperature had dropped from 50 degrees the previous afternoon to 20 below zero. There were mountainous snowdrifts against anything that slowed the wind. And the river was completely frozen over.

"It was disorienting because all of the familiar colors were gone. Everything was white or gray," Rollie said. "My dad wanted to get off the river right away and find a phone. He knew my mom would be frantic."

Together the men kicked and clawed the snow away from their boat and pulled it down to the frozen river channel. Lawrence dug out a spud bar, a 5-foot-long, heavy metal tool, and began checking the ice on the channel. "He walked all the way out to the middle thumping the ice every step," Rollie said. "I was pretty relieved when I saw him turn and come back for me."

The two then pushed their boat across the ice, ready to jump in if the ice gave way.

They were aided by a ferocious tailwind. The same wind was denying members of the Coast Guard, waiting on shore, from pushing their 22-foot dory boats onto the ice-choked river to rescue other trapped duck hunters.

"We had never been really worried until the Coast Guard guys told us about all the hunters who had died," Rollie said. "When my dad heard that, he immediately waded through the snow to a home near our cabin where he knew there was a phone and called my mom. She had been fearing the worst."

In retrospect, Lawrence and Rollie Chapple agreed that the record-breaking low pressure of the storm and its effect on the elder man's back had given them a heads-up. Their lack of trust in their outboard motor plus their extra clothing and food convinced them to hunker down and survive one bad storm.