The above graphic shows preferred areas for tropical storm formation in the month of July to be over the Gulf of Mexico, the western Caribbean Sea, and off the southeast U.S. coast similar to June, but we also start looking to the east over the tropical Atlantic during July.
The historical data from the National Hurricane Center show that 109 tropical storms have formed in July from 1851 through 2011.
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During the satellite era, which started in 1966, we have seen an average of one named storm form somewhere in the Atlantic Basin during July. And, on average, we have one hurricane about every other year during this month.
Of course, those are averages and there is a lot of variability. We saw five tropical storms form during July in 2005 with three of those becoming hurricanes (including two major hurricanes). Last year, three tropical storms developed during the month of July, and one of them made landfall on the lower Texas coast. Yet, many years have had no storms develop in this month.