When Does Hurricane Season Start?

Hurricane season in the Atlantic Basin, which includes the Caribbean and the Gulf of Mexico, officially runs June 1 to Nov. 30. There have been tropical storms and hurricanes before June 1 and after Nov. 30, but those are exceedingly rare.

"Usually the bulk of activity is in August through October," said Chris Landsea of NOAA's Atlantic Oceanographic & Meteorological Laboratory. "June and July are typically not good indicators for the rest of the season," Landsea told LiveScience, a sister site to Life's Little Mysteries.

The reason hurricanes occur during these months is that they need warm water, which feeds a storm with energy, in order to form. For a hurricane to have enough energy to form and keep going, the water must be at least 80 degrees Fahrenheit (26.5 Celsius) down to at least 150 feet (50 meters), scientists estimate. The atmosphere must also be laden with moisture.

This year, an “active to extremely active” hurricane season is expected in the Atlantic Basin, according to NOAA. There will be 14 to 23 "named storms," which have top winds of 39 mph (63 kph) or higher, according to NOAA's predictions. These named storms are predicted to include eight to 14 hurricanes, which have top winds of 74 mph (119 kph) or higher, and three to seven of these could be major hurricanes, which are hurricanes with winds of 111 mph (178 kph) or higher. The average season brings 11 named storms, six hurricanes and two major hurricanes.

“If this outlook holds true, this season could be one of the more active on record,” said Jane Lubchenco, under secretary of commerce for oceans and atmosphere and NOAA administrator.

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