El Niño is expected to switch over to the La Niña climate pattern this summer, and with this shift comes an increased likelihood of hurricanes in the Atlantic.
With El Niño, the ocean surface warms. While the weather pattern has been in effect, global temperatures were the warmest on record last month and the previous month, according to the National Oceanic and Atmospheric Administration. In the U.S., May was also marked by wild weather.
“There were 11 individual billion-dollar weather and climate events across the U.S. during the first five months of 2024, each with losses exceeding $1 billion,” according to NOAA. “These disasters consisted of nine severe storm events and two winter storms. The total cost of these events exceeds $25 billion, and they have resulted in at least 84 fatalities.”
Michigan’s first ever tornado emergency was also issued last month by the NWS for an EF-2 storm on May 7. That week, WWJ reported that four tornadoes hit the state. Overall, spring precipitation was 1.32 inches above average this year, and many states saw some of their wettest springs on record.
In mid-May, Audacy reported that El Niño would transition into La Niña this summer and the most recent hurricane update from NOAA said there is a 77% likelihood of La Niña conditions. La Niña has an opposite effect on ocean temperature than El Niño, according to the NOAA. With it comes strong trade winds that push warm water towards Asia.
“La Niña tends to reinforce those high-activity era conditions and further increases the likelihood of an above-normal season,” explained NOAA’s 2024 Atlantic Hurricane Season Outlook. According to this outlook – which covers the North Atlantic Ocean, Caribbean Sea, and Gulf of Mexico – an above-normal season is most likely, “with low possibilities the season could be near-normal and even lower odds for a below-normal season.”
By percentages, the likelihood of an above-normal hurricane season is pretty high at 85%. There’s a slim, 10%, chance of a “normal” season and just a 5% chance of a below-normal season. The season actually began June 1 and it runs through the end of November.
What those percentages means in terms of actual storms is difficult to predict exactly. However, NOAA offered these range estimates with a probability of 70%: 17 to 25 named storms, eight to 13 hurricanes, four to seven major hurricanes, and an Accumulated Cyclone Energy (ACE) range of 150%-245% of the median.
Another hurricane season outlook update is expected in August.
Although La Niña is expected to be a factor this hurricane season, a “set of conditions that have produced the ongoing high-activity era for Atlantic hurricanes which began in 1995 are likely to continue in 2024,” said NOAA. “These conditions include warmer sea-surface temperatures (SSTs) and weaker trade winds in the Atlantic hurricane Main Development Region (MDR), along with weaker vertical wind shear, and an enhanced West African monsoon.”
As of May 23, SSTs in the MDR were at record warm levels, similar to those normally observed in late July and early August.
“The 2024 North Atlantic hurricane season could be the eighth out of the last 10 with above-average activity. Since the current Atlantic high-activity era began in 1995, 20 of 29 (about 70%) seasons have had above-normal activity, and only 5 (17%) and 4 (14%) have had near- and below-normal activity, respectively, based on the 1951-2020 climatology,” said NOAA.