The forecast for the 2023 Atlantic hurricane season is ‘close to normal’, but there is a wild card

After a few years of heightened risk, the Atlantic hurricane season is shaping up to look pretty average by 2023. That’s thanks to an unusually long-lasting weather pattern called La Niña finally ending, and its counterpart, El Niño, expected. develop soon. The caveat is that there is more uncertainty in this year’s seasonal forecast than normal due to unusually warm temperatures in the Atlantic.

Those factors tend to have opposite effects in hurricane season. El Niño generally ushers in milder storms in the Atlantic. But warmer waters provide more fuel for tropical storms to strengthen. So we’ll have to wait and see how these competing forces factor into this year’s season.

There is a 40 percent chance of a “near normal” Atlantic hurricane season this year, according to a forecast released today by the National Oceanic and Atmospheric Administration (NOAA). But there is also a 30 percent chance that “above normal season, as well as a 30 percent chance of abelow normal season when it comes to storm activity.

Between 12 and 17 storms are expected to grow strong enough to earn a name (reaching wind speeds of at least 39 miles per hour), NOAA predicts. Of those named storms, five to nine are expected to intensify into hurricanes. NOAA is also anticipating up to four major hurricanes this year. For comparison, between 1991 and 2020, there were an average of 14.4 named storms, 7.2 hurricanes, and 3.2 major hurricanes per season.

Even with a “near normal” season, coastal communities still need to be prepared, officials warned at a news conference today. “Remember, it only takes one storm to devastate a community, regardless of the statistics I shared,” NOAA Administrator Rick Spinrad said. “If one of those named storms is hitting your home or your community, it’s very serious.”

Over the past several years, La Niña has set the stage for more intense storms to develop in the Atlantic. Both La Niña and El Niño are part of a recurring weather pattern that can influence weather around the world. In the Atlantic, La Niña tends to reduce vertical wind shear that might otherwise have prevented a tropical storm from intensifying.

La Niña finally came to an end in March, and El Niño is now expected to develop in the coming months. El Niño can generally soften hurricane season because vertical wind shear increases, which can tear storms apart as they try to strengthen.

Climate change also affects the hurricane season. Storms draw strength from thermal energy at the sea surface. So with global warming, hurricanes have become more intense. And recently, sea surface temperatures in the tropical Atlantic Ocean and Caribbean Sea have been warmer than normal for this time of year.

Similar to NOAA, another seasonal forecast in April from Colorado State University predicted a “slightly below average” season. He also emphasized the great uncertainty in this season’s forecast based on the strange combination of forces brewing in the Atlantic this year.

Typhoon Mawar has just dealt a heavy blow to Guam, a US territory in the Pacific where the storm season starts a bit early. Mawar made landfall there Wednesday night as the strongest storm to hit the territory in two decades before intensifying into a super typhoon with wind speeds exceeding 150 miles per hour.

“We are waking up to a rather disturbing scene across Guam. We’re looking out our door, and what used to be a jungle looks like toothpicks. looks like a scene from the movie Twisterwith trees torn apart…Most of Guam is likely dealing with a major mess that will take weeks to clean up,” a National Weather Service meteorologist said in a Facebook Live update this morning.

FEMA Administrator Deanne Criswell said the storm shows how important it is to prepare for the upcoming Atlantic season. “As we see the impacts of Super Typhoon Mawar, what we see is that these types of events are increasing and intensifying faster,” she said at today’s press conference. “No matter how many named storms there are, no matter what time of year, whether we’re at the peak of hurricane season or not, it only takes one.”