Hurricane Warnings in Effect
Atlantic:  High Seas

The Ocean Prediction Center and "The Perfect Storm"

The Halloween Nor'easter of 1991 brought great destruction to the northeast coast of the United States, created waves that were felt as far south as Florida, the Bahamas, and even Puerto Rico, and threatened the lives of hundreds of mariners. Dubbed "The Perfect Storm" by National Weather Service (NWS) meteorologist Bob Case, this remarkable weather event cost the 6-person crew of the Andrea Gail their lives as the storm exploded around then in late October 1991.

Every day, forecasters at the NWS Ocean Prediction Center formerly the Marine Prediction Center, located in the Washington suburb of Camp Springs, Maryland, prepare the weather warnings and forecasts for the high-seas areas of the north Pacific and north Atlantic, including those remote fishing sites far from the New England coast visited by the Andrea Gail. These forecasts are transmitted to mariners many ways, including marine radiofacsimile for graphics, single-side-band and satellite transmission of text forecasts, and voice forecasts over WWV. Additionally, all of OPC's products are available on this web site.

With the aid of complex weather forecast models of the atmosphere, imagery from NOAA weather satellites, and their own experience in predicting maritime weather, OPC forecasters focused their attention on the north Atlantic in late October 1991. Although a number of monstrous storms with waves in excess of 50 feet occur every winter in the North Atlantic and Pacific, this particular weather situation seemed especially ominous as OPC forecasters anticipated three major weather features interacting vigorously to produce ideal conditions for a life-threatening storm. One feature was a cold front that passed through New England and into the north Atlantic where it developed a frontal low-pressure center southeast of the Canadian maritime provinces. Behind this system a very large high-pressure system intensified (to a near-record 1046 millibars) over eastern North America, an important ingredient for Nor'easters. Making matters even worse, Hurricane Grace was making its way northward off the U.S. coast, pumping significant amounts of moisture toward the frontal low-pressure center.

On October 27, OPC forecasters sounded the alarm that a major storm was developing in the north Atlantic within the next 36 hours. The next morning OPC forecasters referred to the developing system as a "dangerous storm" in their broadcast to mariners. This was one of the first times OPC forecasters used this term and reflected the seriousness of the situation. That evening the frontal low-pressure center, tapping the moisture and energy from the hurricane, the high-pressure system, and the ocean itself, intensified very, very rapidly right over the position of last radio contact from the Andrea Gail. The storm continued to deepen through the morning of October 30, then blocked by the immense high to its north moved westward toward the U.S. coast, an unusual event. The combination of wind-driven water (known as storm surge) of 4-5 feet above normal tides, waves up to 25 feet high some places along the coast, and the long duration of the storm, which meant that the coastline was pounded by heavy surf through a number of tidal cycles, led to extensive damage of structures and beaches along the coast from North Carolina northward to Canada.

This storm was well forecast by the OPC and other NWS forecast offices. Nevertheless, with the support of the U.S. taxpayers OPC has made significant progress in improving its products and services since that time. To learn more about the OPC and how it has changed since "The Perfect Storm", please click here.

Jim Hoke
Former Director, Ocean Prediction Center