20 cyclones attaining tropical depression status,
19 cyclones attaining tropical storm status,
9 cyclones attaining hurricane status,
5 cyclones attaining major hurricane status.
This prediction is well above the 1991-2020 averages of 14.4 tropical storms, 7.2 hurricanes, and 3.2 major hurricanes each season in the Atlantic basin. I expect that 2022 will thus be the third consecutive season with significantly above-average activity. Below, I'll discuss the various factors involved in making this prediction.
The first factor to consider is, as always, the El Niño Southern Oscillation (ENSO) index, which is a numerical measure of sea surface temperature anomalies in the equitorial Pacific ocean. When these waters are warmer than normal (El Niño), Pacific tropical cyclone activity is elevated and Atlantic activity is suppressed. When they are cooler (La Niña), the reverse is true. Remarkably, La Niña conditions are expected to persist through the summer, making 2022 the third consecutive La Niña year! The graphic below shows various model predictions for the ENSO index through the rest of the year. The official threshold for a La Niña event is -0.5, and the index is expected to linger near or below this threshold by a majority of models.
The map below shows current sea surface temperature anomalies in the Atlantic. They are mostly above average, though no region in particular stands out too much. Note that sea surface temperature anomalies are generally measured relative to a mean based on the last few decades. Therefore, this does not account for anthropogenic ocean warming; measured against pre-industrial levels, these anomalies would be greater.
Until May, the main developement region (between the western African coast and the Caribbean) actually had somewhat below average sea surface temperatures. Recently, however, the east-to-west trade winds have relaxed. When trade winds are strong, they churn up cooler ocean waters from below the surface; they also directly inhibit cyclone formation by making it hard for vortices to form (see here for more). Therefore, recent trends are concerning, as the eastern Atlantic has warmed significantly in the last month. If this continues, long-track hurricanes are likely by the heart of the season. Finally, we'll take a look at the following prediction for wind shear anomalies in the first half of hurricane season (June-July-August).
Blue indicates below-average wind shear and hence more favorable conditions for hurricanes to form. The signal in this model is quite strong; it seems likely that the Caribbean in particular will have little wind shear during early hurricane season. Note that below-average shear is consistent with a La Niña pattern, but this doesn't occur everywhere: in the deep tropics near Africa, there's an area of above-average shear. In this model, the region of above-average shear even drifts northward as the summer progresses. Nevertheless, almost all factors point to a quite active hurricane season.
Using these and a few other factors, I'll give a finer analysis of the risks by region. My estimates are on a scale from 1 (least risk) to 5 (most risk).
U.S. East Coast: 4
Most areas are at above-average risk this year, and the east coast is no exception. The good news is that I expect most of the cyclones forming in the main development region during August and September will curve out to sea, since the shear pattern favors the consolidation of tropical waves more at their northern ends. Storms forming closer to home will be the ones to watch for.
Yucatan Peninsula and Central America: 4
The monsoon in this region is currently quite active. This elevates the risk for some messy tropical storms near central America in late May and June, with flooding and mudslides the main concern. It's difficult to say this early, but October and November may also be an active time for the western Caribbean.
Caribbean Islands: 4
All the general factors discussed above also suggest the Caribbean will be at elevated risk, but I don't see anything specific pointing to tracks through the islands. I do expect an early start to activity in the region, with multiple storms by the time August comes around.
Gulf of Mexico: 5
The Gulf coast has experienced an exceptional number of hurricane landfalls already during the 2020 and 2021 seasons. With the La Niña continuing, this is unlikely to abate this year, unfortunately. The atmospheric setup on models this year also seems to favor steering cyclones into the Gulf, should they form in the Caribbean. This merits a maximum risk designation.
Overall, I expect the 2022 Atlantic hurricane season to be well above average. Nevertheless, this is just an amateur forecast. Individuals in hurricane-prone areas should always have emergency measures in place. For more on hurricane safety sources, see here. Remember, devastating storms can occur even in otherwise quiet seasons.
Sources: https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf, https://www.tropicaltidbits.com, https://www.trackthetropics.com/saharan-air-layer-sal-tracking/, https://www.nhc.noaa.gov/sst/
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