At a Glance

A total of 13named storms, five hurricanes and two major hurricanes are expected this season.This is nearthe 30-year average of 12 named storms, six hurricanes and three major hurricanes.The forecast was released Thursday by the Colorado State University Tropical Meteorology Project.

The 2019 Atlantic hurricane season may see fewer storms and hurricanes, but that doesn't necessarily mean it will be less dangerous, according to a newly released outlook from the .

(MORE: Hurricane Central)

The group led by calls for a total of 13 named storms, five hurricanes and two major hurricanes.

This is near the 30-year average of 12 named storms, six hurricanes and three major hurricanes. A major hurricane is one that is Category 3 or stronger on the.

Numbers of Atlantic Basin named storms (those that attain at least tropical or subtropical storm strength), hurricanes, and hurricanes of Category 3 intensity forecast by Colorado State University compared to the 30-year average and totals from the 2018 season.

(Forecast: Tropical Meteorology Project/Colorado State University)

Though the officialAtlantic hurricane season runs from June through November, occasionally we can see storms develop outside those months, as was the case in the previous two seasons with May 2018's Tropical Storm Alberto and April 2017's Tropical Storm Arlene.

(MORE: Why the 2018 Hurricane Season Was More Active Than Predicted)

The CSU outlook is based onmore than 30years of statistical predictors, combined with seasons exhibiting similar features of sea-level pressure and sea-surface temperatures in the Atlantic and eastern Pacific Oceans.

Here are some questions and answers about what this outlookmeans.

What Does This Mean For the U.S.?

There is no strong correlation between the number of storms or hurricanes and U.S. landfalls in any given season. One or more of the 13 named storms predicted to develop this season could hit the U.S. or none at all. Therefore, residents of the coastal United States should prepare each year no matter the forecast.

A couple of examples of why you need to be prepared each year occurred in 1992 and 1983.

The 1992 season produced only six named storms and one subtropical storm. However, one of those named storms was Hurricane Andrew, which devastated South Florida as a Category 5 hurricane.

In 1983 there were only four named storms, but one of them was . The Category 3 hurricane hit the Houston-Galveston area and caused almost as many direct fatalities there as Andrew did in South Florida.

In contrast, the 2010 Atlantic season was quite active, with 19 named storms and 12 hurricanes. Despite the large number of storms that year, not a single hurricane and only one tropical storm made landfall in the United States.

In other words, a season can deliver many storms but have little impact or deliver few storms and have one or more hitting the U.S. coast with major impact.

Named storm tracks in the 2018 Atlantic hurricane season. The colors correspond to intensities of each named storm during that section of the track, except for the black sections, which correspond to either a remnant or the time during which a system was a tropical wave before forming into a depression or storm.

The U.S. averages one to two hurricane landfalls each season, according to.

The past two hurricane seasons have been particularly destructive.

In 2018, four named storms impacted the U.S. coast, most notably Hurricanes , then within a month of each other.

In 2017, seven named storms impacted theU.S. coast, including Puerto Rico, most notably hurricanes , and , which batteredTexas, Florida and Puerto Rico, respectively.

(MORE: Three Category 4 Hurricanes Made a U.S. Landfall in 2017)

In 2016, five named storms impacted the Southeast U.S. coast. The most notable was with its powerful scraping of the coast and subsequent inland rainfall flooding.

In the past three seasons, eight hurricanes were so destructive and/or deadly from further use by the World Meteorological Organization.

Before then, the number of U.S. landfalls had been well below average over the previous 10 years.

The 10-year running total of U.S. hurricane landfalls from 2006 through2015was seven,according to a meteorologist with the National Weather Service. This was a record low for any 10-year period dating to 1850, considerably lower than the average of 17 per 10-year period dating to 1850,.

What's more, none of the U.S. landfalls from 2006 through 2015 involved major hurricanes.

Bottom line: It's impossible to know for certain if a U.S. hurricane strike, or multiple strikes, will occur this season. Keep in mind, however, that even a weak tropical storm hitting the U.S. can cause major impacts, particularly if it moves slowly, resulting in flooding rainfall.

How Much of a Role Will El Niño Play?

One ingredient worth attention is El Niño, the periodic warming of the central and eastern equatorial waters of the Pacific Ocean.

As of early spring, a and may be gaining some strength. Klotzbach noted March upper ocean heat content in the area of the equatorial Pacific monitored for El Niño was .

Long-range forecasters at both NOAA and The Weather Company, an business, now believe there's a good chance this El Niño will persist into at least the summer, if not into the fall, during the heart of the hurricane season.

(IN DEPTH: Category 6 Blog on the 2019 Season Outlook)

Sea-surface temperature anomalies during the last week of March 2019. Surface temperatures warmer than average are shown by the yellow, orange and red contours. Those colder than average are shown by the blue contours. Red arrows highlight the weak El Niño, or warmer-than-average water around the equatorial Pacific Ocean.

(NOAA/ESRL/PSD)

El Niño tends to produce areas of stronger wind shear (the change in wind speed with height) and sinking air in parts of the Atlantic Basin that are hostile to either the development or maintenance of tropical cyclones.

With the major exception of Michael, this wind shear was a factor keeping the Caribbean Sea rather quiet in the 2018 season, as evidenced by the relative dearth of Caribbean tracks in the 2018 track map above.

The effects of El Niño in the eastern Pacific, Caribbean and western Atlantic Ocean.

But there are several important caveats to this.

Stronger-than-average wind shear was present in the Caribbean Sea in 2018 without an official El Niño. The wind shear suppressed development in the Caribbean but not elsewhere in the Atlantic.

Any Other Factors in Play?

El Niño is only one of several influences on the atmospheric circulation. Water temperatures in the Atlantic have a much more direct role in tropical cyclone development on the Atlantic side of the continent.

The current water temperatures across the North Atlantic basin show cooler-than-average water temperatures in the far North Atlantic and in the eastern tropical Atlantic between the Lesser Antilles and Africa. Warmer-than-average water is widespread in the Gulf of Mexico, off the southeast coast of the U.S. and in the central Atlantic Ocean.

March 2019 Atlantic Basin sea-surface temperature anomalies. Water warmer than average, including the Gulf of Mexico, western and central Atlantic Ocean is shown by the green, yellow, orange and red contours. Colder-than-average ocean surface temperatures are shown in the blue and purple contours.

(NOAA ESRL Physical Sciences Division)

While emphasizing large uncertainty in what water temperatures will be in the North Atlantic during the peak of hurricane season, Klotzbach noted the early spring configuration of water temperature anomalies lined up with previous below-average hurricane seasons.

However, it isn't the anomalies that allow hurricanes to intensify, but rather the actual heat of the oceans.

Water temperatures of 80 degrees or higher are generally supportive oftropical storm and hurricane formation and development.

Much of the tropics stay at or above this temperature for most of the year.

So why bring it up if favorable conditions are always around?

If temperatures in the main development region (MDR) between Africa and the Caribbean Sea are warmer than average, we often get more than the average number of tropical storms and hurricanes from this region. Conversely, below-average ocean temperatures can lead to fewer tropical storms than if waters were warmer.

Warmer waters in the MDR allow tropical waves, the formative engines that can become tropical storms, to get closer to the Caribbean and United States.

Other factors that can be detrimental to tropical storm or hurricane development include dry air and wind shear.

In and there was prohibitive dry air and/or wind shear during a significant part of the season, but El Niño was nowhere to be found.

This was the third April outlook issued since the passing ofDr. William Gray,noted hurricane researcher and emeritus professor of atmospheric science at Colorado State University.

Gray, who died in April of 2016,was thecreator of the yearly Atlantic hurricane season outlooks, which have been published every year since 1984. He developed the parameters for these outlooks in the late 1960s, which was considered groundbreaking research at that time.