Hurricane season will be above average

The 2020 Atlantic hurricane season begins officially in the Cayman Islands on June 1 and a total of 16 named storms, eight hurricanes and four major hurricanes are expected which is slightly above average.

The season ends at the end of November and it is above the 30-year average of 12 named storms, six hurricanes and three major hurricanes.

The forecast was released by the Colorado State University (CSU) Tropical Meteorology Project. With the US currently facing more than one million cases of COVID-19 and a death toll of more than 60,000 so far, the hurricane season will further stretch resources and emergency services already under extreme pressure.

The CSU forecast also predicts 80 named storm days, up from the average of 59.4 days, during the 2020 season. It places the probability of landfall of a major hurricane in the US at about 130 percent of the long-term average, based on hurricane season activity from 1981-2010.

Cayman residents are already well prepared for the hurricane season partly because of the measures they had to take for the coronavirus lockdown. Hurricane Ivan had a devastating effect on Grand Cayman in 2004 and Palermo struck Cayman Brac and Little Cayman in 2008 so for many Cayman residents the need for preparedness is foremost in their minds.

The National Oceanic and Atmospheric Agency (NOAA) recently published its spring outlook, pointing to regions along the US east coast being 60-70 percent warmer than normal. The predicted summer outlook for the same areas looks like being even higher than that figure.

Early preparedness is vital as storms can occasionally develop outside June-November, as happened in the past three seasons with May 2019's Subtropical Storm Andrea, May 2018's Tropical Storm Alberto and April 2017's Tropical Storm Arlene.

"The consensus is an above-average season is coming up," said Philip Klotzbach, a hurricane researcher at CSU. The likelihood of more cyclones means boosted odds of storms hitting land, and communities. "In general, more active hurricane seasons have more landing hurricanes," Klotzbach said.

Early indications are worrying. Over the past five years or so tropical storms in May have occurred more often than in the past record. There are indications this could be another such season by the end of this month.

Although the early season could be busy, most of the prediction models point to near-neutral conditions or a weak La Nina in the Pacific for the heart of the season August-October. Thanks in part to the mild winter and the Atlantic and Gulf of Mexico/Caribbean Sea-surface water temperatures are above normal, and in some areas warm enough to support cyclogenesis.

CSU said the team bases its forecasts on a statistical model, as well as two new models that use a combination of statistical information and forecasts from dynamical models from the United Kingdom Met Office and the European Centre for Medium-Range Weather Forecasts.

These models are built on 25-40 years of historical hurricane seasons and evaluate conditions including Atlantic sea surface temperatures, sea level pressures, vertical wind shear levels (the change in wind direction and speed with height in the atmosphere), El Niño (warming of waters in the central and eastern tropical Pacific), among other factors.

Last year was the fourth consecutive season with above-average named storms in the Atlantic and Caribbean regions. Most of the storms were weak and short-lived, but there was a total of 18 named storms and six hurricanes in 2019.

The 2019 season was also the fifth year in a row where a tropical or subtropical cyclone developed before the official start of the season on June 1. The old record was four years in a row from the 1951 through the 1954 seasons.

So far, it said the 2020 hurricane season is exhibiting characteristics similar to 1960, 1966, 1980, 1996 and 2008. “1966, 1980, 1996 and 2008 had above-average Atlantic hurricane activity, while 1960 was a near-average hurricane season,” said Klotzbach.

The 2019 season was most notable for Hurricane Dorian, which devastated the north-western Bahamas, and for Tropical Storm Imelda, which caused tremendous flooding in portions of southeast Texas. The CSU team will issue forecast updates on June 4, July 7 and August 6.