Washington Post chief meteorologist Philip Klotzbach projects the exact average strength of the upcoming Atlantic hurricane season, which will officially open on June 1. The seasonal average is 12 named storms (spreads of at least 39 millibars in pressure), six hurricanes (4.4 above average), two major hurricanes (3.3 above average). The 2011 Atlantic season averaged 15 named storms, 10 hurricanes and five major hurricanes, whereas the 2010 season averaged 13 named storms, 10 hurricanes and six major hurricanes.
Surface ocean heat content, ocean surface winds and storm totals are indicative of what we can expect in the Atlantic in any given season. Extreme ocean heat content and winds have historically enabled monster storms such as Sandy to form. For this season, Klotzbach says his team’s models show that the first two months could be more temperate than the warm period from 2010-11, which could lead to fewer storms as the summer deepens and stronger storms build up.
Klotzbach notes that the 2011 season was extraordinary, with 19 named storms, the most in a decade. “They don’t get more unusually intense than they were last year, and we won’t go back down to 1979,” he said.
August 12-October 31 average intensity of storms
The average intensity of storms, and major hurricanes, are shown in a chart. The red line denotes the predicted season average. The two purple line projects the typical season for the Atlantic basin.
Seasons average intensity for storms and major hurricanes
The categories of storms and hurricanes represent the severity of the storm. All the storms are shown in an orange box, ranked according to their intensity by Klotzbach, Ed Thornton and Jeff Masters.
Category 1: Hurricane conditions
Category 2: Catastrophic hurricane conditions
Category 3: Catastrophic hurricane conditions
Category 4: Catastrophic hurricane conditions
Category 5: Catastrophic hurricane conditions
Category 6: Catastrophic hurricane conditions
Alberto and Alberto look set to form this season. Over the past century, Alberto has been associated with an active Atlantic hurricane season.
Barbuda is likely to experience tornadoes in August.
September sea surface temperatures in the region could be cooler than the climatological average.
In October, sea surface temperatures in the region could be cooler than the climatological average.
Washington D.C. will see more tropical storm activity this season.
With over a week to go before the official start of the season, Klotzbach expects more tropical storm activity this year than any other since 2000. Expect Tropical Storm Irma to be the first major hurricane of the season and Hurricane Jose to strengthen in the Atlantic. Jose will most likely move westward before shifting southwesterly in the second half of August. A developing Hurricane Katia will remain off the east coast of Florida, an area that Klotzbach expects will see 11-15 named storms. September sea surface temperatures in the region could be cooler than the climatological average.
By May, powerful tropical cyclones come and go.
Klotzbach’s team typically sees 80-90 named storms in an average season, but can sometimes see as many as 114 storms. That number doesn’t take into account Florida when it is in the middle of its season, as the one-week cycle changes weather patterns and affects the Atlantic Atlantic basin. In fact, Klotzbach’s team expects that the area of strong easterly winds over the central Atlantic this year will cut down on the number of storms from the beginning of June to August. Assembling this data allows the researchers to forecast hurricane seasons years out, and vice versa.
Florida at the head of the year.
Klotzbach predicts that the strongest hurricane of the year will form in Florida in late August. The forecasting models have him using August 21 as the historical landfall day, a date that was recently reached for Tropical Storm Ernesto. In 2014, this date was used to forecast Floyd, who caused billions of dollars in damage, while Dennis was forecast to reach Florida in June 2011 and weakened as it neared land. Klotzbach notes that other countries are also likely to see storms during the summer. He notes that New Zealand will see about five storms between July 1 and November 30, Ireland will have five storms, and the Turks and Caicos Islands will see at least one.