1991 HALLOWEEN NOR'EASTER

The '1991 Halloween Nor’easter', also known as the 'Perfect Storm', was an unusual nor’easter which was extratropical, absorbed one hurricane, and ultimately evolved into a small hurricane late in its life cycle. The unnamed hurricane of 1991 was the last tropical cyclone of the 1991 Atlantic hurricane season, and its 4 hurricane. By November 2, Atlantic Canada experienced the effects of a landfalling tropical storm. Damage totals neared $1 billion (1991 USD) and deaths climbed to 12 people. Most of the damage occurred while the storm was extratropical. The hurricane was the second costliest storm of the season, behind only Hurricane Bob, which caused $1.5 billion (1991 USD, $2.1 billion 2005 USD).

Contents

Storm history

Impact

Naming

Quotations

See also

External links

Notes and references

Storm history

A low pressure system which initially formed in Indiana moved east-northeast into Atlantic Canada. By October 28, the system had become a deepening extratropical cyclone east of Nova Scotia. The system moved east-southeast and then curved to the west due to a blocking ridge in the far northern Atlantic. Hurricane Grace was swept aloft by its cold front into the warm conveyor belt circulation of the deep cyclone on October 29.

The Halloween Storm reached peak intensity at approximately 12:00 UTC 30 October 1991 with the lowest pressure being 972 millibars. This extratropical cyclone, with its associated high winds from the pressure gradient between the high to its northeast and its low pressure center, created large waves. NOAA buoy 44011 located at 41.1° N, 66.6° W reported maximum sustained winds of 49 knots (91 km/h) with gusts to 65 kt (120 km/h) and a significant wave height of 39 feet (12 m) near 15:00 UTC. Buoy 44008 located at 40.5° N, 69.5° W reported maximum sustained winds of 53 kt with gusts to 63 kt (117 km/h) and a significant wave height of 31 ft (9 m) near 00:00 UTC on October 31. Other, higher waves (such as the one shown in the film dramatization ''The Perfect Storm'') of 100'+ height were reported by ships, but not confirmed by buoys.


The core of the storm, which moved southwards, ended up over warmer Gulf Stream waters and began to develop the convection (thunderstorms, rain, etc.) of a tropical storm early on November 1. It later strengthened into a true hurricane, with minimum pressure of 980 mbar and sustained winds of 75 mph (120 km/h), making it a category 1 hurricane. Since the northeast of the United States had already received a pounding from the main storm, and the hurricane was forecast to remain offshore, it did not receive a name and is known as the Unnamed Hurricane of 1991. The hurricane continued to the northeast, and dissipated on November 2 after making landfall on Nova Scotia as a tropical storm with 50 (statute) mph (80 km/h) winds.

Impact

The Halloween Storm of 1991 was costly; Walter Drag, Senior Forecaster at the Boston National Weather Service office, estimated the cost of the storm to be under 1 billion U.S. dollars. It caused 12 confirmed deaths; including 6 onboard the ''Andrea Gail'' and one Air National Guard pararescue jumper. It lashed northeastern U.S. with a storm tide of more than 14 ft (4 m) above a storm surge of approximately 5 ft (1.5 m), and piled on top of that 30 ft (10 m) waves. The worst of the storm stayed offshore.

Naming

The U.S. Department of Commerce, National Oceanic and Atmospheric Administration NWS Natural Disaster Survey Report called the storm "The Halloween Nor’easter of 1991". The "perfect storm" moniker was coined by author and journalist Sebastian Junger after a conversation with NWS Boston Deputy Meteorologist Robert Case in which Case described the convergence of weather factors as being "perfect" for the formation of such a storm.^[1][2] In New England it is still colloquially referred to as simply "the No Name Storm" or "the Halloween Storm." Had it been given a name, it would have been called 'Hurricane Henri'.

Quotations

See also

★ Halloween Blizzard

★ List of notable Atlantic hurricanes

★ List of New England hurricanes

★ Perfect storm

External links

★ Summary of the storm and its formation, with satellite imagery

★ News article covering the storm

★ NWS Service Assessment

★ Semi-official report

★ The unnamed hurricane spawned by the storm

Notes and references

1. (2000, June 29). "Meteorologists Say 'Perfect Storm' Not So Perfect", ''Science Daily''
2. West, James. (2000, July 6). "The naming of 'The Perfect Storm'", ''USA Today''