Monday, November 15, 2010

The Witch of November

I've been away from writing for about 10 days but didn't want to miss the opportunity to mark last week's 70th anniversary of one of the most deadly winter storms in U.S. history.

The Great Lakes and Upper Midwest frequently are recipients of vicious autumn storms, which are known in that area as the Witches of November.

Typically, a deep trough (low pressure system) over the Upper Midwest or in Canada causes a buckling in the jet stream, and strong storm systems ride that current of air. Frequently, these storms move inland off the West Coast, dive southward in the Great Plains, and then surge northeastward across the Midwest or Great Lakes.

As was the case with such a storm system Oct. 26 and 27, these low pressure systems can have amazingly low barometric pressures -- equal to those of Category 2 hurricanes. Normally, the result is a wind machine and sometimes a blizzard.

While the Oct. 26-27 storm set records for low barometric pressure, meteorologists usually point to the Armistice Day Storm of 1940 as the most memorable in weather history.

For some reason, many of these storms seem to form on Nov. 10 or 11, and the Armistice Day Storm was, of course, a Nov. 11 event.

It killed more than 150 people, including more than 60 sailors on ships that sank in Lake Michigan and dozens of duck hunters in Minnesota and Iowa.

The storm came with little warning, as the U.S. Weather Bureau of that time was still developing its forecasting methods. Temperatures were in the low 40s as the low pressure system swept into Iowa, Wisconsin and Minnesota, but those readings plummeted to single digits in some parts of Minnesota.

Stories of the time tell of duck hunters who were on small islands in the Mississippi River when the storm arrived. They tried to take shelter, but many drowned when the 50 mph sustained winds (with gusts around 80 mph) created waves of 4 and 5 feet on the river and inundated the hunting camps. Others died of exposure to the cold.

Nearly 17 inches of snow accumulated in Minneapolis-St. Paul, and drifts of up to 20 feet were reported in the region.

With much more sophisticated forecasting tools and better communication systems today, an Armistice Day Storm still could cause plenty of problems but almost certainly wouldn't leave such a death toll.

The Carolinas aren't immune to such a powerful cold-season storm system. A similar storm swept across the Southeast and the East Coast in March 1993, you might remember. That storm produced record snowfall in parts of Alabama, Georgia, Tennessee, the Carolinas, Virginia, Pennsylvania, West Virginia, Maryland and New York.

The immediate Charlotte area escaped with only a few inches of snow, but Carolinas mountain residents measured the snow in feet.


Anonymous said...

And let's not forget the impact one of these storms had on the Edmund Fitzgerald... Broken in half by the storm, all hands on board were lost...

Anonymous said...

The wind in the wires made a tattletale sound
And a wave broke over the railing
And every man knew, as the Captain did, too,
T'was the witch of November come stealing.

Anonymous said...

As soon as I read the title I thought you were going to talk about the storm that wrecked the Edmund Fitzgerald.

Anonymous said...

As big freighters go, she was bigger than most.

Anonymous said...

How could anyone even write this article WITHOUT mentioning the Edmund Fitzgerald?

Anonymous said...

So glad you're back, Steve! We've missed you. Love this blog!