At a Glance
July brings slightly more hurricanes and tropical storms to the west Atlantic and Gulf of Mexico.The area where tropical development occurs expands eastward and northward.The second month of hurricane season has produced a few notable storms.
Atlantic hurricane season is usually still slow in July, but there is a slight uptick in activity and the areas of potential development begin to expand farther east into the Atlantic Ocean.
July has accounted for only 8% of the Atlantic hurricane season's named storms since 1851, according to NOAA's Hurricane Research Division. That pales in comparison to the percentage of named storms that have formed in busiest months of hurricane season: August (25%), September (40%) and October (23%).
From 1950-2018, 67 named storms formed in July, averaging about one named storm in July each year. Incidentally, the Atlantic season's first named storm will have formed by the second week of July in a typical season.
Of those named storms from 1950-2018, 29 strengthened to hurricanes, for an average of one July hurricane every two to three years.
July 2018 was unusual since both Beryl and Chris formed into hurricanes during the month. That marked the first time since 2008 the Atlantic had a pair of July hurricanes.
Major hurricanes, Category 3 or stronger on the Saffir-Simpson Hurricane Wind Scale, in July are rare. Only five major hurricanes have flared up during the hurricane season's second month since 1950.
A Subtle Shift East
July is a month of transition. Formation areas spread east to include more of the Atlantic Ocean to the east of the Lesser Antilles.
Tropical waves, one of the seeds for tropical storm development, become a bit better defined in July. That's one reason we begin to look farther east in the second month of hurricane season.
The Gulf of Mexico remains somewhat active in July, though the western Caribbean Sea steps down a bit as cold fronts become far less frequent.
Development can also occur from north of Hispañiola to north of the Bahamas. Those storms can either linger off the East Coast and churn up high surf that causes beach erosion and rip currents, curl or recurve harmlessly out into the open Atlantic, or in more rare cases, make landfall along parts of the East Coast.
Only five July hurricanes have made landfall along the East Coast since 1950, none reaching Category 3 strength.
These are all averages. Not every July follows the script.
Recent July Activity
In the last 15 years, there have been notable July storms.
Over the Fourth of July holiday in 2014, Hurricane Arthur raked eastern North Carolina and the Outer Banks with storm surge flooding and strong winds.
Hurricane Alex made landfall in July 2010 in northern Mexico. Its torrential rain flooded the Rio Grande Valley and Monterrey, Mexico.
On July 3, 2008, Tropical Storm Bertha became the farthest east named storm to form in the Atlantic Basin so early in the season in the satellite era (since 1966). Bertha was also the longest-lived July named storm on record. It lasted 17 days in the open waters of the Atlantic Ocean.
Also in July 2008, Category 2 Hurricane Dolly made landfall in southern Texas.
The record-smashing 2005 hurricane season was active in July, when five name storms formed.
After Hurricane Cindy hit southeast Louisiana, Hurricane Dennis was, at the time, the strongest July Atlantic Basin hurricane on record. It made landfall in the Florida Panhandle.
Just six days after Dennis made landfall, Hurricane Emily became the only Category 5 July hurricane of record in the Atlantic Basin. It churned in the Caribbean Sea before striking Cancun and Cozumel, Mexico.