2.3 April Analog Forecast Scheme

Certain years in the historical record have global oceanic and atmospheric trends
which are similar to 2024. These years also provide useful clues as to likely levels of
activity that the forthcoming 2024 hurricane season may bring. For this early April
extended range forecast, we determine which of the prior years in our database have
distinct trends in key environmental conditions which are similar to current March 2024
conditions and, more importantly, projected August–October 2024 conditions. Table 12
lists our analog selections, while Figure 12 shows the composite August–October SST in
our five analog years.

We searched for years that were generally characterized by El Niño conditions the
previous winter and had La Niña conditions during the peak of the Atlantic hurricane
season (August–October). We also selected years that had well above-average SSTs in
the tropical Atlantic, although none of these years had SSTs in the tropical Atlantic in
March that were as warm as they are now. We anticipate that the 2024 hurricane season
will have activity near the average of our five analog years for most parameters. The busy
hurricane seasons in all analog years underscore the higher-than-normal confidence in an
active 2024 hurricane season. Named storm activity was likely significantly
underestimated in 1878 and 1926 given the extremely limited observational network
available in those years."