The Category 5 hurricane is unleashing catastrophic winds and torrential rain as officials urge everyone in Jamaica to stay indoors and shelter in place.

It also marks the first time in 20 years that three or more Category 5 hurricanes have developed over the Atlantic Basin in one season. The last time was in 2005, when Hurricanes Emily, Katrina, Rita, and Wilma all reached Category 5—breaking a record.

According to the NHC, the Saffir-Simpson Hurricane Wind Scale, developed in 1971 by civil engineer Herbert Saffir and meteorologist Robert Homer Simpson, is a rating of 1 to 5 based on a hurricane's sustained wind speed and its potential for significant loss of life and damage.

Matthew Cappucci, a senior meteorologist at MyRadar and storm chaser, spoke with NBC News’ Kate Snow about his experience flying into the eye of Hurricane Melissa aboard a NOAA aircraft and the concerns over the Category 5 storm making landfall.

Jamaica is bracing for potentially its strongest storm to ever impact the island, as the slow-moving, major Category 5 hurricane closes in. AccuWeather's Leslie Hudson reports from Lake County, FL, where 16 inches of rain in 6 hours triggered a rare flash flood emergency, washing out roads and flooding homes.

Melissa developed into a deadly Category 5 hurricane Monday, Oct. 27, and is expected to have historically catastrophic impacts on the northern Caribbean.

Track the latest forecasts for Hurricane Melissa with USA TODAY's storm tracker for Saturday, Oct. 25. The National Hurricane Center reports Melissa has strengthened into a hurricane in the Caribbean on Oct.

Melissa’s 185 mph winds rival the most intense Atlantic storms on record. The Category 5 hurricane is threatening Jamaica with a storm surge of up to 13 feet.