University of Pennsylvania EES scientists Dr. Michael E. Mann and Shannon Christiansen, and Penn State ESSC alumnus Dr. Michael Kozar have released their seasonal prediction for the 2024 North Atlantic hurricane season, which officially starts on 1 June and runs through 30 November.
The prediction is for 33.1 +/- 5.8 total named tropical cyclones, which corresponds to a range between 27 and 39 storms, with a best estimate of 33 named storms. This prediction was made using the statistical model of Kozar et al. (2012, see PDF here). This statistical model builds upon the past work of Sabbatelli and Mann (2007, see PDF here) by considering a larger number of climate predictors and including corrections for the historical undercount of events (see footnotes).
The assumptions behind this forecast are (a) the persistence of current North Atlantic Main Development Region (MDR) sea surface temperature (SST) anomalies (+1.9°C in April 2024 from NOAA’s Coral Reef Watch) throughout the 2024 hurricane season, (b) development of a moderate La Nina (Niño3.4 anomaly of -0.5°C) conditions in the equatorial Pacific in late Boreal summer and fall 2024 (ENSO forecasts here; we used mid-April 2023), and (c) climatological mean conditions for the North Atlantic Oscillation in Fall/Winter 2023-2024.
If neutral ENSO conditions (Niño3.4 anomaly of 0.0°C) take shape later in 2024, then the prediction will be lower: 30.5 +/- 5.5 storms (range of 25 – 36 storms, with a best guess of 31).
Using an alternative model that uses “relative” MDR SST (MDR SST with the average tropical mean SST subtracted) in place of MDR SST yields a lower prediction (19.9 +/- 4.5 total named storms). This alternative model also includes positive ENSO conditions.
Previous Forecasts:
| Year | Prediction | Best Guess | Range | Actual Count |
|---|---|---|---|---|
| 2023 | 15.9 +/- 4.0 | 16 | 12-20 | 20 |
| 2022 | 14.9 +/- 3.8 | 15 | 11-19 | 14 |
| 2021 | 11.9 +/- 3.4 | 12 | 9-15 | 21 |
| 2020 | 19.8 +/- 4.4 | 20 | 15-24 | 30 |
| 2019 | 10.1 +/- 3.2 | 10 | 7-13 | 18 |
| 2018 | 10.2 +/- 3.2 | 10 | 7-13 | 15 |
| 2017 | 15.3 +/- 3.9 | 15 | 11-20 | 17 |
| 2016 | 18.9 +/- 4.4 | 19 | 14-24 | 15 |
| 2015 | 6.9 +/- 2.6 | 7 | 4-10 | 11 |
| 2014 | 9.3 +/- 3.0 | 9 | 6-12 | 8 |
| 2013 | 16.0 +/- 4.0 | 16 | 12-20 | 14 |
| 2012 | 11.2 +/- 3.3 | 11 | 8-15 | 19 |
| 2011 | 16.25 +/- 4.0 | 16 | 12-20 | 19 |
| 2010 | 23.4 +/- 4.8 | 23 | 19-28 | 19 |
| 2009 | 11.5 +/- 3.4 | 12 | 8-15 (6-13 if El Niño) | 9 |
| 2007 | n/a | 15 | n/a | 15 |
References:
Kozar, M.E., Mann, M.E., Camargo, S.J., Kossin, J.P., Evans, J.L., 2012: Stratified statistical models of North Atlantic basin-wide and regional tropical cyclone counts, J. Geophys. Res., 117, D18103, doi:10.1029/2011JD017170.
Mann, M.E., Sabbatelli, T.A., Neu, U., 2007: Evidence for a Modest Undercount Bias in Early Historical Atlantic Tropical Cyclone Counts, Geophys. Res. Lett., 34, L22707, doi:10.1029/2007GL031781.
Sabbatelli, T.A., Mann, M.E., 2007: The Influence of Climate State Variables on Atlantic Tropical Cyclone Occurrence Rates, J. Geophys. Res., 112, D17114, doi: 10.1029/2007JD008385.
Vecchi, G.A., Knutson, T.R., 2008: On Estimates of Historical North Atlantic Tropical Cyclone Activity, J.Climate, 21, 3580-3600, doi:10.1175/2008JCLI2178.
Footnotes:
The tropical cyclone series was corrected based on an estimated historical undercount taken from Vecchi and Knutson (2008).
Prediction made: April 11, 2024
This webpage last updated: April 23, 2024