Below-Average Activity Seen for Rest of Hurricane Season

Scientists at Colorado State University’s Tropical Meteorology Project have decreased their forecast and now believe that 2018 hurricane season will have below-average activity.

According to the forecasters, the tropical and subtropical Atlantic is currently much colder than normal, and the odds of a weak El Nino developing in the next several months have increased. With the decrease in the forecast, the probability for major hurricanes making landfall along the U.S.coastline and in the Caribbean has decreased as well, report Philip J. Klotzbach and Michael M. Bell.

The Colorado team now estimates that the rest of 2018 will see an additional four hurricanes (median is 6.5), 10 named storms (median is 12.0), 41.50 named storm days (median is 60.1), 15 hurricane days (median is 21.3), one major (Category 3-4-5) hurricane (median is 2.0) and two major hurricane days (median is 3.9). The forecast cites a 22 percent probability of a direct hit to the eastern United States; the average is 31 percent.

This revised prediction is a decrease from the group’s prior seasonal forecasts issued in April and June and some uncertainty remains with this forecast. It is based on an extended-range early July statistical prediction scheme that was developed utilizing 36 years of past data.

In explaining the changed forecast, the researchers note that the tropical Atlantic is much colder than normal.

“A colder than normal tropical Atlantic provides less fuel for developing tropical cyclones but also tends to be associated with higher pressure and a more stable atmosphere,” the forecasters note. “These conditions tend to suppress Atlantic hurricane activity.”

Also, the odds of a weak El Nino for the peak of the Atlantic hurricane season in 2018 have increased somewhat. If El Nino were to develop, it would tend to lead to “more vertical wind shear in the Caribbean extending into the tropical Atlantic, tearing apart hurricanes as they are trying to develop and intensify,” according to the new forecast.

Topics Catastrophe Natural Disasters Hurricane