The National Oceanic and Atmospheric Administration expects an “above normal” Atlantic hurricane season this year, the agency announced on Tuesday. If that plays out, it would make 2022 the seventh consecutive year with an above-normal season.

Rick Spinrad, the NOAA administrator, said at a news conference on Tuesday that scientists had calculated a 65 percent chance of an above-normal season, a 25 percent chance of a near-normal season, and a 10 percent chance of a below-normal season.

The season — which officially runs from June 1 through Nov. 30, though storms can develop outside that period — is likely to include 14 to 21 named storms, a category that includes all tropical cyclones with top winds of at least 39 miles per hour. Of those, six to 10 are expected to reach hurricane strength, meaning sustained winds of at least 74 miles per hour. And of that subset, three to six are expected to reach Category 3 or higher, meaning sustained winds of at least 111 miles per hour.

NOAA’s seasonal forecast is for overall Atlantic hurricane activity and does not predict how many storms will pass near or over land.

But “it only takes one storm to damage your home, neighborhood and community,” Mr. Spinrad said. “Preparedness is key to resilience, and now is the time to get ready for the upcoming hurricane season.”

Several elements informed the forecast, among them La Niña, a broad climatic pattern that has been in place on and off since 2020 and affects many aspects of weather, including the drought in the Western United States. La Niña is expected to persist through the entire hurricane season, maintaining conditions that are conducive to hurricane formation.

Another factor is a strong West African monsoon, which supports the development of areas of low atmospheric pressure known as African easterly waves, from which intense storms can form. At the same time, the tropical Atlantic trade winds are weaker than average, which makes it easier for a developing storm to coalesce without being ripped apart by wind shear. NOAA also expects unusually warm sea surface temperatures in the Atlantic Ocean this summer, and storms gain strength as they pass over warm water.

The classification system NOAA uses — which categorizes events of increasing intensity as tropical depressions, tropical storms and Category 1 through Category 5 hurricanes — is based solely on maximum sustained wind speeds and does not reflect the volume or intensity of rainfall.

But rainfall and flooding can oftentimes cause more damage than wind, and the destruction can extend far beyond the Southern coastal regions that are most commonly affected by hurricanes. Early last September, the remnants of Hurricane Ida devastated the New York metropolitan area with more than three inches of rain in one hour, even though its winds had fallen well below hurricane strength by that point.

Broadly, many of the patterns that have led to above-average hurricane seasons, and to other extreme weather, are related to climate change.

Climate change is producing more powerful storms, and they dump more water because of heavier rainfall and a tendency to dawdle and meander; rising seas and slower storms can make for higher and more destructive storm surges. But humans play a part in making storm damage more expensive, as well, by continuing to build in vulnerable coastal areas.

“We’re seeing such a dramatic change in the type of weather events that we’re facing as a result of climate change,” Deanne Criswell, the administrator of the Federal Emergency Management Agency, said on Tuesday, emphasizing the need for individual preparedness.

As the season unfolds, forecasters will be watching the Loop Current, a warm area in the Caribbean and the Gulf of Mexico. Its positioning varies from year to year, and smaller currents known as eddies can separate from the main current, bringing warmer-than-average water farther north in the Gulf.

This is not a factor in the seasonal forecast because the effects depend on the geography of individual storms, said Matthew Rosencrans, the NOAA Climate Prediction Center’s lead hurricane forecaster. If a storm’s path doesn’t take it over the current, it isn’t relevant. But storms that cross the Loop Current or an eddy can intensify rapidly and dangerously, as Hurricanes Katrina and Rita did in 2005 — and the current this year looks much like it did in 2005.

“The Loop Current does look like it’s active this year; we are seeing that push of warm water up into the Gulf,” Mr. Rosencrans said. “If a storm forms and then does move over top of where the Loop Current is, it can be an explosive source of energy.”

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