The 2015 Atlantic hurricane season is officially underway.

Last week, the National Oceanic and Atmospheric Administration released its Atlantic hurricane outlook, predicting a below-normal season with 6-11 named storms, 3-6 hurricanes and as many as two major hurricanes.

Hurricane season runs from June 1 to Nov. 30. This season's first storm, Tropical Storm Ana, didn't happen during the season's official window.

Ana made landfall near Myrtle Beach, South Carolina.

The tropics remained quiet Monday, with no potential development in the forecast over the next five days.

Ana was included in the forecast NOAA released Wednesday, May 27:

"A below-normal season doesn't mean we're off the hook," said NOAA Administrator Kathryn Sullivan. "As we've seen before, below-normal seasons can still produce catastrophic impacts to communities."

Sullivan referred to the 1992 hurricane season, when only seven storms were named, but the first was Andrew, which devastated South Florida as a Category 5 hurricane.

It's been 11 years since four hurricanes, including Charley (pictured above) made landfall in Florida, and 10 since hurricanes Katrina and Rita devastated the Gulf Coast.

The weather phenomenon called El Nino generally means fewer hurricanes. But the head of the National Weather Service's Climate Prediction Center, Mike Halpert, said in March that this year's El Nino is happening late and is weak.

Colorado State University scientists William Gray and Philip Klotzbach said in April that they expect one of the least active seasons since the mid 20th century, based on the chance of an El Nino of at least moderate strength this summer and fall. Their early prediction was for seven named storms, three of them hurricanes, and one of those hurricanes major.

(39 mph or greater)
(74 mph or greater)
MAJOR HURRICANES (111 mph or greater)
2015 forecast (NOAA) 6–11 3–6 0–2
2015 forecast (Klotzbach/Gray) 7 3 1
2014 (actual)
8 6 2
2013 (actual) 14 2 0
2012 (actual) 19 10 2
2011 (actual) 19 7 4
2010 (actual) 19 12 5

Klotzbach said the El Nino has strengthened considerably since March.

"At this point, it is best to characterize it as a moderate-strength event, and we anticipate the event to likely be strong by the peak of the Atlantic hurricane season," he wrote in an email to the Associated Press. "A strong El Nino will likely significantly reduce storm formation in the Atlantic basin."

El Nino is a warming in one part of the central Pacific. It changes weather patterns worldwide. In addition to fewer Atlantic hurricanes, El Ninos are associated with flooding in some places, droughts elsewhere and generally warmer global temperatures.

Information from The Associated Press was used in this report.