2020 Hurricane Season Update

October 6, 2020 // Article by: Mike Mihalik

The 2020 hurricane season has been off to a blistering fast start with nine named storms already, two of which have been hurricanes. The storms began developing in mid-May and several have had impacts on the U.S. In fact, five storms have made a U.S. landfall so far in 2020 - Bertha, Cristobal, Fay, Hanna, and Isaias. Hanna and Isaias were both category 1 hurricanes, with Isaias certainly creating the most impact across the Northeast. With Isaias, coastal areas in the Mid-Atlantic reported 75 mph wind gusts and inland locations even topped 50 mph gusts. 5 - 9 inches of rainfall was reported from eastern MD into eastern PA with notable flash flooding. 10 tornadoes were also confirmed, most of which occurred in PA and NJ. In total, Isaias accounted for over 3 million power outages, with NJ, NY, and CT hit the hardest. 

Flooding in Bethlehem, PA during Isaias.

So where does the tropical season go from here? Well from what we can tell, the tropics look to remain condusive for development as we head into the peak of the season (spiking in mid-September). Water temperatures will continue to be above normal from the Gulf into the western Atlantic and Caribbean. Tropical waves will be abundantly produced off of Africa, leading to more long-track storms. And finally, wind shear should stay weaker than normal, thanks to a developing La Niña, so storms shouldn't be ripped apart too much by upper level winds.

Sea surface temperature anomalies, showing warmer than average water in orange/red. The cooler waters near the Southeast U.S. coast and off the mid-Atlantic are due to Isaias and will be temporary. Courtesy Tropical Tidbits.

With the potential for the tropics to keep churning out storms, the big question is, "Where will they track and will they impact the U.S?" Well, the steering pattern doesn't look to be changing any time soon. Tropical waves will continue to move off of Africa and enter the western Atlantic with no trouble. Additional impacts to land are certainly likely, but it's too early to say whether the storms will be favored to hit the Caribbean, Gulf Coast, Bahamas, Southeast U.S, or ride up the East Coast.

Example of the most common steering pattern for the rest of the hurricane season. Notice the bubble of "ridginess" over the North Atlantic steering storms off of Africa, west into the Carribean or Bahamas. Courtesy of Tropical Tidbits.

As for numbers, our original hurricane season forecast called for 14 - 19 named storms, 7 - 11 hurricanes and 3 - 6 major hurricanes (average numbers are 12-6-3). While this was certainly an above average forecast, taking into account the 9 storms already and the potential for activity to ramp up through August and September, we now think 19 - 25 named storms, 8 - 12 hurricanes, and 3 - 6 major hurricanes are possible for the season as a whole. To put that in perspective, the most active Atlantic hurricane season on record was 2005, in which there were 28 named storms. In fact the National Hurricane Center ran out of storm names that year, and began using the Greek alphabet. Let's hope we don't enter that territory in 2020.