Kei Uesugi | Stone | Getty Images
A hurricane watch was issued Wednesday for part of North Carolina as the first named tropical storm of the season gathered strength and threatened July Fourth celebrations along the East Coast.
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The National Hurricane Center said Tropical Storm Arthur was slowly drifting north and becoming better organized, and forecasters said it could become a minor hurricane by Thursday. Overnight, a tropical storm watch was in effect for part of Florida's east coast. The Weather Channel senior meteorologist David Houtz told NBC News that Arthur will likely affect Florida the most on Wednesday, with gusty winds and showers.
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—By Cassandra Vinograd, NBC News