Update June 16, 2024 at 12:45 a.m.
After several months of El Niño rule, eastern Pacific waters have officially entered a neutral phase, with temperatures hovering near normal.
But this phase should not last. In its most recent forecast, NOAA predicts that temperatures are expected to continue to drop so that a transition to La Niña could occur sooner than expected.
As a reminder, La Niña occurs when surface temperatures in the tropical zone of the eastern Pacific Ocean are abnormally low.
According to NOAA, there is a 75% chance that the phenomenon will take hold between August and October. However, this period, far from being trivial, also corresponds to the peak of cyclonic activity in the Atlantic basin.
Why is this bad news?
Although localized, changes in eastern Pacific water temperatures have impacts on global atmospheric circulation. While the Pacific basin could experience a drop in cyclone activity, the opposite effect will occur in the Atlantic.
With Atlantic waters already very warm and the favorable conditions created by La Niña, the hurricane season is expected to be more active than expected. In fact, the presence of strong winds previously limited the formation of hurricanes. However, the arrival of the phenomenon is generally accompanied by a smaller variation in the wind. The ingredients will therefore be gathered for a particularly active season.
A hyperactive year
And NOAA’s forecasts reflect this phenomenon. While there are an average of 14 named storms, this number could rise to 25 in 2024. The same story goes for hurricanes which could be twice as numerous this year.
The announcement of a more active season also comes with a higher risk of coastal impacts. The regions in the heart of the Gulf of Mexico and on the American east coast will be worth watching, but it is the Caribbean which will be the most exposed.
