The 1984 Atlantic hurricane season was the most active since 1971, though the season was below average in hurricanes and major hurricanes. It officially began on June 1, 1984, and lasted until November 30, 1984. These dates conventionally delimit the period of each year when most tropical cyclones form in the Atlantic basin. The 1984 season was an active one in terms of named storms, but most of them were weak and stayed at sea. Most of the cyclones tracked through the northwest subtropical Atlantic west of the 50th meridian to near the Eastern coast of the United States between mid-August and early October. The most damaging storm was Hurricane Klaus, which caused $152 million (1984 dollars) in damage in Puerto Rico. Hurricane Diana was the first hurricane to strike a nuclear power plant without incident; it was also the first major hurricane to strike the U.S. East Coast in nearly 20 years. Also of note was Hurricane Lili, which lasted well after the official end of the season. It was downgraded from a named storm on December 24. Damage overall from the tropical cyclones in 1984 totaled $228.7 million (1984 USD). Unusually, no hurricanes developed from tropical waves in 1984, which usually are the source of the strongest storms in an Atlantic hurricane season. Seasonal forecasts Forecasts of hurricane activity are issued before each hurricane season by noted hurricane experts such as Dr. William M. Gray and his associates at Colorado State University (CSU). A normal season, as defined by the National Oceanic and Atmospheric Administration (NOAA) in the period from 1981 to 2010, has approximately 12 named storms, with 6 of those reaching hurricane status. About 3 hurricanes strengthen into major hurricanes, which are tropical cyclones that reach at least Category 3 intensity on the Saffir–Simpson scale. Early in 1984, the Weather Research Center (WRC) forecast called for a below-average season with seven named storms, with four of those strengthening into a hurricane. The May 24, 1984, forecasters at CSU predicted a near-average season with a total of 10 tropical storms developing, 7 of which would reach hurricane status. CSU based this prediction on the presence of an El Niño, the Quasi-biennial oscillation, and favorable sea-level pressures over the Caribbean Sea and Gulf of Mexico. These numbers were unchanged in CSU's next season outlook, issued on July 30. None of these predictions included a forecast for the number