MIAMI, USA (AP) — Epsilon rapidly gained major hurricane strength on Wednesday afternoon and is expected to skirt east of Bermuda in the coming day, the US National Hurricane Center says.

The Category 3 storm is packing top sustained winds of 115 mph (185 kph) and Bermuda remains under a tropical storm warning. Epsilon gained 50 mph (80 kph) in wind speed in just 24 hours, officially qualifying as a rapidly intensifying storm. It is the seventh storm this season to power up this quickly.

The Miami-based hurricane center said Epsilon was located at 8:00 pm EDT about 315 miles (510 kilometers) southeast of Bermuda, and was moving to the west-northwest at 10 mph (17 kph).

Forecasters said Epsilon should make its closest approach to Bermuda by Thursday afternoon or evening. Gradual weakening of the storm is expected to begin on Thursday and continue into the weekend.

Over the past couple decades, meteorologists have been increasingly worried about storms that blow up from nothing to a whopper, just like Epsilon. Forecasters created an official threshold for this dangerous rapid intensification — a storm gaining 35 mph (56 kph) in wind speed in just 24 hours.