An Unnamed January Subtropical Storm Kicked Off Hurricane Season Early, NHC Says

The Atlantic hurricane season started early with the first storm forming in January, according to a statement released by the National Hurricane Center (NHC) Thursday.​

A​n unnamed subtropical storm formed in mid-January. A powerful storm system off the East Coast had its area of low pressure obtain enough thunderstorms near its core to be deemed a hybrid subtropical storm, as depicted in the yellow and orange shadings in the satellite view of the system from the evening of Jan. 16.

"Through the course of typical re-assessment of weather systems in the National Hurricane Center's area of responsibility, NHC hurricane specialists have determined that an area of low pressure that formed off the northeastern coast of the United States in mid-January should be designated as a subtropical storm," the NHC said in a statement.

Subtropical storms are usually named in real-time. Subtropical storms have characteristics of both tropical storms and the more commonly seen non-tropical low-pressure systems. They are usually assigned a number or name, just like a tropical depression or storm.

T​his one was tracked in real-time by NOAA and was deemed Invest 90L, which is a naming convention used to identify systems in the Atlantic that have some chance to form into a tropical/subtropical depression or storm. But since it was a marginal case, it was not named one at that time.

(​MORE: Meteorology 101: Learn About Subtropical Storms)

I​f the next Atlantic system is initially a tropical depression, it will be called Tropical Depression Two.

(​MORE: Atlantic Hurricane Season Outlook)

January storms are rare, but the month recently had a hurricane. In January 2016, Subtropical Storm Alex formed in the eastern Atlantic and then became a hurricane.​ It eventually made landfall in the Azores as a tropical storm.

Only five other Atlantic storms have existed in January since record-keeping began.

H​urricane season officially begins June 1, but storms forming before that date have been common in recent years. 2022 snapped a streak of eight years to have at least one storm form prior to that date.

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