Hurricane Facts: How many storms have formed in December?

Joe Mario Pedersen, Orlando Sentinel

The Atlantic hurricane season is over, but that doesn’t mean it’s impossible for a tropical storm to form.

It means it’s really unlikely.

The conditions for a December storm exist in pockets of warm water and little wind shear.

On Wednesday, the National Hurricane Center is keeping its eyes on a gale force, non-tropical low pressure system in the east Atlantic which has a 10% chance of developing into a tropical storm.

If it does, it will be the 31st named storm of the 2020 season and receive the name Kappa.

With how unusual the 2020 has been thus far, it could happen and it would be far from the first storm to develop outside of the season.

There’s a total of 87 recorded storms that have developed outside of the Atlantic hurricane season, according to the National Oceanic and Atmospheric Administration.

However, only five storms in the last 30 years developed in the month of December, said NHC spokesman Dennis Feltgen.

Perhaps the most infamous was 2005 1/4 u2032s Tropical Storm Zeta, which came into formation as a depression on Dec. 30 and has been well cited this year in media reports as the only other year to produce storms designated with Greek letters due to the season’s storm production exhausting the pre-made name list.

The earliest storms on record in the last 30 years were Tropical Storm Odette and Tropical Storm Peter. The former hit Hispaniola on Dec. 6 and caused $8 million in damages, the NHC reports show. At least 10 people died, mostly due to flash floods and mud slides. Odette brought down trees and power lines. It damaged buildings, bridges, and large areas of agricultural land destroying about 35% of its banana crop.

Tropical Storm Olga formed on Dec. 11, 2007 much to the dismay of the Dominican Republic, which reported the deaths of at least 22 people who in large were killed by mudslides, according to the NHC.

“Olga’s impact was unusually severe due to the grounds having been previously saturated from the passage of Tropical Storm Noel at the end of October,” the NHC reported.

Olga was remnants by the time it arrived in Florida. But the dying storm still left a mark in Central Florida when a tornado touched down in Pasco County causing damage to several buildings including a county fire station and the Pasco County Jail.

The most recent December storm took form as an unnamed subtropical storm in 2013. The system caught the eye of meteorologists on Dec. 5 but the system was ripped apart by a strong wind shear, and couldn’t develop further over cold Atlantic water. It decayed on Dec. 7 about 90 miles south of the Azores.

The two elemental factors are exactly why tropical storms as a whole have difficulty forming in December and in other off-season months. The window of opportunity closes from December through May.

However, as history shows, storms can form whenever.

The City of Orlando sent out a tweet Tuesday reminding resident that while hurricane season is over, they should remain prepared for anything.

“Today is officially the last day of hurricane season! But seeing 2020 has been a hurricane in itself, it’s best to stay prepared. Keep your disaster kits stocked with batteries, masks, disinfectants and 7 days worth of non-perishable food,” city officials wrote.


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