(CNN) — Tropical Storm Melissa has formed in the Caribbean Sea, proving this year’s Atlantic hurricane season won’t be wrapping up quietly.

The storm could slam the northern Caribbean with pouring rain and strong winds as it strengthens over extremely warm water this week. Melissa’s worst impacts could center on Hispaniola, where significant flooding and dangerous mudslides are possible for parts of the Dominican Republic and Haiti through the weekend.

Melissa was churning about 300 miles south of Haiti with maximum sustained winds of 50 mph as of late Tuesday morning, according to the National Hurricane Center.

The storm is expected to hit hurricane status by Saturday, according to the center, but it’s still tough to pin down exactly how strong it will become from there.

A hurrican

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