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There’s a scary new hurricane season forecast but the tropics remain calm

Aug. 6 satellite image of the tropics.
Aug. 6 satellite image of the tropics. (CIRA/RAMMB)

The updated prediction from Colorado State University is for a super-active hurricane season the rest of the way. The CSU team is forecasting 15 more named storms and 10 more hurricanes, with half of them being Category 3 or stronger.

If this seems like a lot, it is. It means a total of 24 named storms counting the nine we’ve already had. Only one season in the record book had a higher total of named storms, and that was 2005, which was off the charts using up 28 names. It’s likely that 1933 was also in that realm. Officially, there were 21 tropical storms and hurricanes that year, but none were detected in the eastern Atlantic in that pre-satellite era, so unquestionably there were more. 

The CSU prediction is based on three factors: the trade winds over the Caribbean, the ocean temperature in the eastern Atlantic near southern Europe and northwestern Africa, and the upper winds over Africa.

Factors in Colorado State Forecast.
Factors in Colorado State Forecast. (CSU)

The wind almost always blows from east to west over the Caribbean Sea, but in years when the wind is relatively light, the tropical ocean temperatures are warm because the wind stirs up less cool water beneath the surface.

Second, when the ocean temperature is warm in the box off northwestern Africa, the wind flow over the tropical Atlantic tends to be more favorable for storm development.

And third, the upper winds over Africa correlate with how many disturbances will develop over the tropical Atlantic. On average, when the winds are like they are this year, more systems organize.

Much of this relates to the forecast for El Niño or La Niña in the Pacific. The oceanographic/atmospheric system is connected around the world. El Niño years have fewer hurricanes because the heat in the tropical-Pacific waters creates hostile winds over the Atlantic. In La Niña years, however, the opposite occurs. 

This year, the El Niño/La Niña effect is favoring La Niña, so negative effects from El Niño’s upper winds are not expected. 

Plus, Mother Nature has been on a tear generating named storms. The net net is that many more storms than normal are forecast.

Dr. Phil Klotzbach, who leads the Colorado State team, talked about the factors involved in the forecast on the Bryan Norcross Podcast a couple of weeks ago.

Hurricane specialists and researchers at the National Hurricane Center and their parent organization, NOAA, will announce their updated forecast today, which is likely to indicate a well-above-average season as well.

The main take-away is, the odds favor a significant number of storms developing in the tropical Atlantic, where serious storms often form that hit the U.S. East Coast and Florida. Since preparation and information are our only defenses, our path is clear. 

Right now in the Atlantic, there is a weak disturbance well off the Southeast coast. It is surrounded by dry air and is unlikely to amount to anything.

Way out in the tropical Atlantic between Africa and the Caribbean, where we will be watching disturbances later this month, dry air and hostile upper winds are dominating for now. So no tropical development is expected into early next week, at least. 


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