The hurricane season is off to a stormy start in the Atlantic this year, setting new records.
The latest was Hurricane Isais, which left at least five people dead as it ripped through the eastern United States this week and was the earliest ninth named storm in history.
And many are storms are to come, according to the U.S. National Oceanic and Atmospheric Administration (NOAA), which has updated its Atlantic storm predictions for 2020.
Usually, only two named storms form by August, and typically 12 named storms will form throughout the season, with six becoming hurricanes and three developing into major hurricanes.
On Thursday, however, the NOAA announced it is expecting 19 to 25 named storms with seven to 11 becoming hurricanes, three to six of them being major hurricanes.
That’s up from the earlier forecast of 13 to 19 named storms (storms with wind speeds over 63 km/h), of which six to 10 would become hurricanes.
“This is one of the most active seasonal forecasts that NOAA has produced in its 22-year history of hurricane outlooks,” U.S. Secretary of Commerce Wilbur Ross stated as the likelihood of an above-normal Atlantic hurricane season soars to 85%. When NOAA’s original forecast was made in May, the likelihood of an above-average hurricane season was assessed at just 60%.
There are a number of factors that contribute to an increase in storm formation. Water temperatures in the Atlantic and Caribbean are warmer than usual, especially in the area near West Africa and the Leeward Islands where many hurricanes are born.
In addition, western Africa is seeing an especially active monsoon season, which can help form thunderstorms off its coast.
La Niña has also cooled waters of the Pacific, weakening trade winds over the Atlantic and lessening vertical wind shear which can stop a storm in its tracks.
Researchers at NOAA and the University of Wisconsin released a study in June indicating that global warming may also help produce stronger storms that can intensify very rapidly.
While the forecast calls for more windy weather, it also means there could be a shortage of storm names.
If 21 named storms form before the end of the hurricane season, forecasters would have to resort to naming them after the Greek alphabet, a situation that has occurred just once before when there were 27 named storms in 2005.
Colorado State University (CSU) meteorologists also predict stormy weather. In a revised forecast released Wednesday, they speculate that this could be the busiest season on record, with 24 named storms and a total of 12 hurricanes, five of which they predict will be major, meaning sustained winds of more than 179 kilometers per hour.
Thus far this season is on track to surpass 2005, when 15 hurricanes formed causing an estimated 3,912 deaths and approximately US $171.7 billion in damage. Thus far, the number of storms formed is the most ever recorded since the satellite era began in 1966, the NOAA says.
“As is the case with all hurricane seasons, coastal residents are reminded that it only takes one hurricane making landfall to make it an active season for them,” write the CSU forecast’s authors. “They should prepare the same for every season, regardless of how much activity is predicted.”
The Atlantic hurricane season officially ends on November 30.
Source: The Washington Post (en)