At a Glance

The Atlantic hurricane season officially begins in June, but activity is typically slow through July.Most systems form in the western Atlantic or Gulf of Mexico.

Hurricane season has begun, and we've already got something to watch in the tropics. Here's what we typically see early in the hurricane season.

The National Hurricane Center selected the June 1-Nov. 30 dates for the hurricane season because they encompass more than 97 percent of tropical cyclones. But as this year showed, there's a reason those dates only account for 97 percent of storms; to the southwest of Bermuda May 20-21.

Early in the season, we typically do not look at the main development region of the central and eastern Atlantic for tropical storms or hurricanes. We actually look closer to home.

The southeastern U.S. coast, the Gulf of Mexico and the western Caribbean Sea are the breeding grounds for tropical cyclones during June. July is when we start to look a bit farther east since the .

This animation shows the typical formation areas and tracks for named storms in June and July.

The, when tropical storms and hurricanes tend to form more often in the central or eastern Atlantic Oceanfromdisturbancesmoving off the northwestern coast of Africa, generally doesn't begin until early August.

Since storms that form early in the year typically start out closer to land, that can increase the chance of impacts along the U.S. Gulf and Southeast coasts, as well as parts of the Caribbean.

Early Season Activity Is Typically Slow

of the tropical storms since 1851 in the Atlantic have occurred in June and July combined. For comparison, August, September and October have accounted for , respectively.

Tropical storm (red) and hurricane (white) frequency by month in the Atlantic Basin.

On average, there's one June named storm in the Atlantic, Caribbean or Gulf of Mexico every one-to-twoyears.July has a slightly higher rate of occurrence, but it's still since 1851.

Hurricanes are even rarer, with just . Last July was a rarity for the Atlantic, with two hurricanes forming in the month: Beryl and Chris. Two or more hurricanes forming in July has only happened .

It's Not Too Early for Major Impacts

in the month of June. It roared ashore in Cameron Parish, Louisiana, as a Category 4 on June 27, 1957.

But it doesn't take an early-season hurricane in June to cause significant impacts.

Take in June 2001. Allison made landfall as a low-end 50-mph tropical storm near Freeport, Texas, and quickly weakened to a tropical depression. The remnants of Allison meandered and lingered for days, allowing a slow-moving rainband associated with it to flare up and unleash epic amounts of rainfall in the Houston metro area, resulting in severe flooding.

In June 1972, made landfall in Florida, but its legacy is more strongly linked to its second wind as a tropical storm, when it curled northwestward toward New York City and stalled over the Northeast, producing flooding rainfall in the interior Northeast.

The most recent hurricane to make a U.S. landfall in July is Arthur in 2014, which raked eastern North Carolina and the Outer Banks with storm-surge flooding and strong winds.

Dolly (2008), Cindy (2005) and Dennis (2005) are the only other three hurricanes to make a U.S. landfall during July in the past 15 years.