MIAMI -- Forecasters say Tropical Storm Isaac is moving westward across the Atlantic on a track that could possibly take it toward Florida, where the Republican National Convention will be held next week.

The National Hurricane Center said Isaac had top sustained winds near 40 mph (64 kph) at 8 p.m. EDT Tuesday night and was expected to strengthen. It was 435 miles (700 kilometers) east of Guadeloupe and heading west near 17 mph (28 kph).

Storm warnings were issued Tuesday across several islands in the Caribbean including Martinique, Guadeloupe and St. Martin.

It's too soon to gauge the storm's exact path. Some computer models forecast Isaac to head toward Cuba and then Florida, while others suggest a sharp northern turn in coming days near Puerto Rico before entering the open Atlantic.

"Monday and Tuesday are definitely in jeopardy," said meteorologist Bill Karins on MSNBC Thursday. "I don't see any way possible that Tampa's going to be completely missed at this point."

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