Hurricane Erin has been downgraded to a Category 3 hurricane but is gaining in size and raising the risk of life-threatening surf later this week along the U.S.

As summer peaks, so does the Atlantic hurricane season, and the first major storm is now on our doorstep. According to the U.S. National Hurricane Center (NHC), Tropical Storm Erin is on a rapid westward path and is projected to strengthen into the Atlantic's first hurricane of the season as early as Thursday,

Tropical Storm Erin making its way across the Atlantic Ocean. What to consider for your Myrtle Beach vacation. August, September and October are the most active months of hurricane season.

Storms that ramp up so quickly complicate forecasting and make it harder for government agencies to plan for emergencies. Hurricane Erick, a Pacific storm that made landfall June 19 in Oaxaca, Mexico, also strengthened rapidly, doubling in intensity in less than a day.