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Universities and private forecasting companies have begun to issue their thoughts on just how active our upcoming Atlantic hurricane season will be and, generally speaking, most predictions are slightly below the average.
To wit, an average season produces 14 tropical storms and, of those storms, seven become hurricanes. Of those seven hurricanes, three will become major Category 3 to five storms (at least 111 mph winds).
Despite dozens of hurricane forecasts each year, Colorado State University started the first such prognostications back in 1984 under William Gray. Since his passing in 2016, Phil Klotzbach (one of his students at the time) has held the reigns. The CSU forecast, being the first, is also one of the most respected and that forecast came out yesterday:
You may recall that 2022, thanks to a lot of Saharan dust during July and August, came in below normal. Yet, Fiona into Canada and Ian into southwest Florida produced life-changing damage and destruction. Indeed, one strong hurricane is all it takes to destroy a community despite such forecasts for low activity.
Saharan dust could be a player again this year (especially in the month of July), but it’s the developing El Nino that is the big reason for lower activity. Those warmer than normal Pacific waters create winds across Central America which can tear up developing hurricanes in the Caribbean and tropical Atlantic.
Obviously, if the El Nino is not as robust as forecast, neither will those winds be and so these below normal forecasts will be completely off the mark. Klotzbach warns of that in his forecast summary. The most recent forecast for El Nino also came out yesterday and I’ve highlighted the red line (above 0°) indicating warmer waters beginning this summer -- that red line is the model consensus but certainly some models predict a stronger El Nino.
So far, the forecasts are looking similar although you will note that University of Arizona is a bit above, so they are not convinced of the El Nino effect. Here’s a chart I made comparing CSU, TWC-The Weather Channel, University of Arizona, AccuWeather, and TSR-Tropical Storm Risk. NOAA’s forecast comes out in May.
As mentioned earlier, one hurricane is all it takes to change lives, so all of this begs the question of just WHERE will these hurricanes go? Colorado State increases the average chance for a U.S. strike by the normal only 1% and the Caribbean by 2%:
• 44 percent for the entire U.S. coastline (average from 1880-2020 is 43 percent)
• 22 percent for the U.S. East Coast including the Florida peninsula (average from 1880- 2020 is 21 percent)
• 28 percent for the Gulf Coast from the Florida panhandle westward to Brownsville (average from 1880-2020 is 27 percent)
• 49 percent for the Caribbean (average from 1880-2020 is 47 percent)
Of course, these are all early predictions and they will all be updated as the actual beginning of the season, June 1, gets closer. In fact, CSU will give us fairly regular predictions all summer and we’ll watch for those to pass them along to you.
Here’s to a pretty nice weekend, just watch those storms tomorrow evening!
Frank
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