The Perfect Storm
October 31, 2000
Just before Halloween 1991, the "Perfect Storm" terrorized sailors and fishermen in the North Atlantic Ocean. Perhaps you read the book "Perfect Storm" by Sebastian Junger or saw the movie based on the chilling account of fishermen trying to survive a real-life nightmare. For those sailors at sea who lived to tell about the storm, this was scarier than any Halloween "creature feature." The color-coded image (red is heavy rain and blue is lighter rain) above shows this terrifying storm as it appeared from the infrared channel on the GOES-7 weather satellite on October 30, 1991. The center of the storm was about 400 miles southeast of Cape Cod.
What was "perfect" about "The Perfect Storm"? Unusual circumstances allowed three weather systems to combine into one monster storm. Hurricane Grace, which had formed off the east coast of Florida on October 27th, weakened as it moved north and was downgraded to a tropical storm. About the same time, an extratropical cyclone developed over southern Canada, and a trailing cold front began to push across the Mid Atlantic States and New England. On October 29, the cold front caught up with the slower moving Grace. Wind shear from the surface front as well as winds aloft acted to tear Grace apart, but the extratropical cyclone absorbed much of her energy. On October 30, as the cyclone moved over warmer Gulf Stream waters it intensified into a super-storm with 100-foot waves and 80 mph winds. This new storm was not named at the time, so now it's referred to as the "Unnamed Hurricane of 1991." The "Perfect Storm" finally broke up over Nova Scotia, Canada, on the 2nd of November. Hybrid storms, such as this one are rare but can be particularly dangerous - some meteorologists say this was perhaps the worst North Atlantic storm in a century.