Professor Quibb's Picks – 2025

My personal prediction for the 2025 North Atlantic Hurricane season (written May 21, 2025) is as follows:

15 cyclones attaining tropical depression status,
13 cyclones attaining tropical storm status,
6 cyclones attaining hurricane status, and
3 cyclones attaining major hurricane status.

This prediction falls just short of the 1991-2020 averages of 14.4 tropical storms, 7.2 hurricanes, and 3.2 major hurricanes each season. I expect 2025 to be near this 30-year average, on the basis of a few different indicators.

We'll begin by checking on two sea surface temperature indicators. The first is north Atlantic sea surface temperature, which has a straightforward correlation with hurricane activity: warmer waters mean more fuel for developing tropical cyclones. In contrast to last year, when ocean temperatures were pratically off the scale, there isn't much to see this year.

The chart above shows sea surface temperature anomalies in the "main development region" for hurricanes in the Atlantic, namely the region of the tropical Atlantic and Caribbean sea extending from Africa in the east to central America in the west. The red line shows anomalies to date in 2025, which, though positive, are nowhere near the extreme warmth of 2024 (orange line) at the moment. The current readings show some support for a higher-than-normal number of hurricanes, but not a strong signal.

The second indicator involving ocean temperatures is the El Niño Southern Oscillation (ENSO) index, a composite measure of the sea surface temperature anomalies in the equitorial Pacific. A more complicated, but well-documented, phenomenon links cooler than average waters in certain Pacific regions to higher-than-normal hurricane activity. I won't spend much time on this indicator, since it's basically a wash:

A small La Niña (negative ENSO index) event prevailed this past winter, but anomalies have now receded to close to the mean, and the various model forecasts are quite mixed as to how things will change from here. In all liklihood, we're in for a neutral ENSO index season, which would suggest average tropical cyclone activity.

As far as other factors go, the picture is similarly muddled. The first part of 2025 saw stronger than normal trade (east-to-west) winds across the tropical Atlantic. This usually leads to more upwelling of cooler subsurface ocean waters and disrupts nascent vortex formation, suppressing cyclone activity. Recent trends show this may be reversing now, however. We can also look at how robust the "tropical wave train" looks coming off of Africa, since this is where many hurricanes get their start.

This enhanced satellite image highlights the Saharan Air Layer (SAL), the dust-laden air mass pushed by trade winds over the Atlantic from the Sahara. This very dry airmass has a habit of stifling would-be hurricanes, and is looking strong so far this year. Similarly, the chart below shows the position of the Intertropical Convergence Zone (ITCZ), an area of instability near the equator that spawns tropical waves.

It is currently positioned south of the climatological normal. If this continues, fewer tropical waves will gain enough latitude to develop; though those that do may have a larger chance of affecting land. Putting all this together suggests a slightly-below-normal hurricane season, but close enough to average that beating the 30-year mean activity would not be a surprise.

Next, 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 and Atlantic Canada: 3
Expectations for an average season apply also to the Atlantic coast of North America. I expect a greater proportion of hurricane activity to be in the western half of the basin this year, but nothing suggests that tracks into land on the east coast are particularly favored.

Yucatan Peninsula and Central America: 4
Unlike the regions farther east, sea surface temperature anomalies have been more robustly positive in the western Caribbean. I expect a greater than usual number of "home-grown" cyclones there, especially of the ITCZ persists south of normal across the Atlantic.

Carribean Islands: 2
The risk is not particularly low for the Carribbean Islands, but long-term precipitation forecasts have this region dominated more often than not with dry, stable airmasses. I'd expect dry air from the Sahara to get the better of tropical cyclones that attempt to head toward the Lesser Antilles in many cases, particularly in the first half of hurricane season.

Gulf of Mexico: 3
There isn't much to suggest particularly above or below average risk to the Gulf of Mexico this year. Waters there are warm, but not notably so, and atmospheric conditions will probably be near average. The period just before the peak of hurricane season will be one to watch here, since cyclones forming in the Caribbean may strengthen and enter the Gulf.

Overall, I expect the 2025 Atlantic hurricane season to be close to average, or perhaps just below. 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.ospo.noaa.gov/products/ocean/sst/anomaly/, https://tropical.colostate.edu/Forecast/2025-04.pdf, https://tropic.ssec.wisc.edu/real-time/sal/, https://www.cpc.ncep.noaa.gov/products/international/itf/itcz.shtml, https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf