Hurricane Alex formed in the Atlantic near the Azores Thursday, becoming the first in January in nearly 80 years, US forecasters said.
The National Hurricane Center said the storm was packing winds of 85 miles per hour (140 kilometers per hour) as it moved toward the Azores.
Hurricane warnings went up in the central portion of the Portuguese islands in the eastern Atlantic.
The NHC said it was the first time a hurricane has formed in January in the Atlantic since 1938.
The storm was expected to dump three to five inches of rain over the Azores, and possible isolated bursts of seven inches, the NHC said.
It warned of the potential for mudslides, flash floods and significant coastal flooding accompanied by large and destructive waves.
Forecasters said it was likely to "lose its identity" within 48 hours as it merges with a large low pressure area at high altitude.
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