1991 Perfect Storm

Two historic storm systems greatly impacted parts of the U.S. during the final days of October 1991. One was "perfect." The other was an early season winter monster.

The "Perfect Storm" has become part of pop culture after the release of the 2000 drama/thriller with the same name. But what exactly made it perfect? It was a combination of weather factors. A combination of a cold front emerging off the northeast United States coast, a developing non-tropical low pressure system near Atlantic Canada, Hurricane Grace spinning near Bermuda and a strong area of high pressure that stretched from the Gulf Coast to eastern Canada.

Even without any influence from Hurricane Grace, the area of low pressure that developed on Oct. 28, 1991 east of Nova Scotia became quite the formidable storm system all by itself. After its birth on that Monday, it quickly intensified on Tuesday, Oct. 29. As it did so, a strong area of high pressure was burgeoning over eastern Canada. This gave way to the development of a tremendous pressure gradient between the high and the lowering pressure of the gale center. The stronger the pressure gradient, the more fierce the winds. And this was a strong pressure gradient.

So again, even before any influence from Grace, winds were already increasing to sustained tropical storm-force near the center of the storm and along New England coast of the United States. Wave heights had been growing in size for two days and propagating toward the U.S. coast.

Then things got more interesting.

It was during Oct. 29 when the large non-tropical low near Nova Scotia began to absorb Hurricane Grace, wrapping in its tropical moisture and likely receiving an injection of energy. You can see the evolution of this development in this YouTube video clip with Stu Ostro’s analysis from The Weather Channel’s coverage of the Perfect Storm.

All the ingredients of the Perfect Storm were now in play. On the morning of Wednesday, Oct. 30, the storm reached its peak intensity as the pressure lowered to 972 millibars. As it peaked in strength, the storm then began to drift southwest toward the New England coast on Wednesday and Halloween.

Next> Damage from the Perfect Storm

Perfect Storm Surface Analysis

Wind gusts exceeding hurricane-force lashed the New England coast on Oct. 30 and 31. Powerful waves battered the East Coast. Tides rose to well above average levels. Damage was extensive, according to the National Climatic Data Center (NCDC).

"Representative peak gusts included: 78 mph at Chatham NWS, 74 mph at Thatcher Island, 68 mph at Marblehead, 64 mph at Blue Hill Observatory (all in Massachusetts) and 63 mph at Newport, R.I.

Even more damaging were the heavy surf and coastal flooding caused by the tremendous seas and high tides caused by the long overwater fetch length and duration of the storm. Waves 10 to 30 feet high were common from North Carolina to Nova Scotia.

A state-by-state damage summary reveals the widespread and extensive damage caused by the storm and accompanying seas. Beach erosion and coastal flooding was severe and widespread, even causing damage to lighthouses. Hundreds of homes and businesses were either knocked from their foundations or simply disappeared. Sea walls, boardwalks, bulkheads and piers were reduced to rubble over a wide area. Numerous small boats were sunk at their berths and thousands of lobster traps were destroyed. Flooding was extensive invading homes and closing roads and airports."

The evolution of the Perfect Storm didn't end there. The final phase involved the development of an unnamed hurricane on Nov. 1 within the center of the overall weakening storm. Yeah, it got weird. Stu Ostro has more on this unnamed hurricane here.

NEXT> Halloween Blizzard of 1991

Halloween Blizzard of 1991

As the Perfect Storm was perfecting its storminess along the New England coast, another (perhaps sometimes forgotten) major winter storm was raging across the Upper Midwest.

A blizzard of historic proportions was dumping feet of snow over the region with the state of Minnesota taking nearly the full brunt of the storm. The severe winter storm has come to be known as the Halloween Blizzard of 1991 or the Great Halloween Megastorm.

The path of this early-season winter storm was pretty remarkable. With the Perfect Storm acting as an atmospheric block on the East Coast, a track from west to east was a no-go. There was only one way to go for the megastorm: north.

The storm developed over the far western Gulf of Mexico on Oct. 30. It strengthened and tracked nearly due north toward Minnesota and Wisconsin on Halloween and Nov. 1. Its tropical moisture connection with the Gulf of Mexico allowed for plentiful available moisture and the resulting big snow totals.

NEXT> Mega Snow Totals

1991 Blizzard Snow Totals

The snowstorm set the largest single storm snowfall record for the city of Minneapolis, dropping more than 2 feet of snow (28.4 inches). In Duluth, Minn., the 37.9 inches of snow that fell was the largest amount on record for the state of Minnesota, surpassing all snow totals from a single storm during any of the winter months. This record was later eclipsed by a lake-effect snowstorm on Jan. 6-8, 1994  when 47 inches fell over Finland in Lake County.

Farther south, with warmer air nosing in, a major ice storm unfolded, with southern Minnesota and the state of Iowa feeling the worst. From the La Crosse, Wis. National Weather Service: "1-2 inches of ice accumulated from southwest Iowa into north central Iowa and 2-3 inches of ice accumulated across south central and southeast Minnesota."

Although many have forgotten this storm because of the attention on the Perfect Storm, those who lived it in Minnesota and Iowa will likely never forget.

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