ORLANDO, Fla. – We’re nearing the official start of the Atlantic hurricane season on June 1, but here’s something you might not know — storms can form before then.
Tropical cyclones don’t always follow the schedule, and we often see early development in areas like the western Caribbean Sea, the Gulf and along the southeastern U.S. coast.
Since 1851, there have been 43 systems with sustained winds of 39 mph or higher that developed between Jan. 1 and May 31 in the Atlantic Basin, according to NOAA’s historical hurricane database. That averages out to about one pre-season storm every four years.
The most recent storm was an unnamed subtropical storm that popped up in January 2023, kicking off the hurricane season a bit earlier than expected. It formed on Jan. 16 and lasted until Jan. 17, making landfall on the northeastern coast of Nova Scotia before quickly weakening into a post-tropical low.
Even though it was short-lived, it definitely gave us an early start to the season, something the National Hurricane Center confirmed in their May 2023 reassessment.
Looking back, there was a seven-year stretch between 2015 and 2021 where at least one storm developed before June 1. So, in the last decade, only 2022 and 2024 didn’t see a pre-season storm.
Pre-season storms happen when the weather conditions align just right, allowing tropical systems to form before hurricane season officially begins.
A big factor is the Central American Gyre, which helps create the perfect environment for storms to develop. Other things like calmer winds, certain atmospheric patterns, and warmer-than-normal ocean temperatures all play a part in making these early storms possible.
Looking ahead, the 2025 hurricane season is expected to be another above-average one. The Colorado State University team recently released their forecast on April 3, predicting 17 named storms, including nine hurricanes, with four potentially becoming major hurricanes. That’s well above the 30-year average of 14 named storms, seven hurricanes, and three major hurricanes.
So, while the official start to hurricane season may be on the horizon, nature doesn’t always play by the rules. It’s always a good idea to be prepared, just in case a storm develops before the season even officially begins.