A leading hurricane season forecast has again reduced its prediction for the number of named storms expected this year to its lowest tally in a decade as a cyclone crushing El Niño deepens to record intensity.
In an update released Wednesday, July 8, Colorado State University is calling for a total of nine named storms to form between now and Nov. 30.
The new prediction, which includes the short-lived and soggy Tropical Storm Arthur, is down from the 13 named storms CSU originally predicted in April. That was lowered to 11 in June, and further reduced to the current nine named storms. Of the nine storms, four are predicted to become hurricanes with one of those becoming a major Category 3 or higher.
The number of hurricanes is down from six that were included in the original forecast. The number of major hurricanes was reduced by one.
“The last year we forecast such a quiet season was in 2015,” said CSU senior research scientist and lead forecaster Phil Klotzbach.
The regularly scheduled July update is completed every year after the atmosphere settles from its spring to summer transition and June helps solidify its intentions. CSU said Wednesday it now anticipates a “well below-normal season.”
Sea surface temperatures in the Caribbean and across the tropical Atlantic are near their long-term averages — a departure from recent years where abnormal warmth in the runway between Africa and the U.S. worked to fuel storms.
“We anticipate the powerful El Niño being the dominant factor for the upcoming hurricane season, driving high levels of tropical Atlantic vertical wind shear,” the report notes.
CSU’s reduction in storms follows a similar decrease by AccuWeather, which announced its updated forecast July 7, calling for a range of 8 to 14 named storms. That’s down from the 11 to 16 storms AccuWeather forecast in March. The new forecast said the “most likely” number of storms is 11.
“El Niño conditions have always been the driver for why we’re expecting numbers near or below the historical average this year,” said Alex DaSilva, AccuWeather lead hurricane expert in a statement. “The stronger the El Niño gets, the fewer named storms we’re likely to get. Back in 2015, we had a strong El Niño and got 11 named storms. I think that is the sweet spot again this year.”
There is record-breaking warmth in the Pacific waters
The Climate Prediction Center will issue its monthly update on the strength of El Niño on Thursday, but meteorologists were already tittering this week about record-breaking warmth in the equatorial Pacific, which is the hallmark of El Niño.
Jeff Berardelli, chief meteorologist for WFLA-TV in Tampa Bay, said in a social media post that the sea surface temperatures are currently 1.1 degrees Fahrenheit warmer than the previous record year of 2015.
“To say El Niño is at record intensity for July is really an understatement,” Berardelli said. “It’s ludicrous, but it’s real. And on track for something beyond super.”
While there is no official definition of a “super El Niño”, a very strong event would be designated if Pacific sea surface temperatures are 2 degrees Celsius or 3.6 degrees Fahrenheit warmer than normal. During the 2015-2016 “Godzilla” El Niño, water temperatures peaked at 2.37 degrees Celsius (4.26 Fahrenheit) warmer than normal.
The warm water shifts thunderstorm patterns in the Pacific, creating more windshear in the Atlantic basin during hurricane season that works to chop up embryonic systems before they can form strong storms.
WPLG Channel 10 hurricane expert Michael Lowry said typically there is a stall between the formation of El Niño and it linking up with the atmosphere to start the windshear machine.
“This year, however, it appears we’re seeing that atmospheric feedback to the strengthening El Niño earlier than usual, which could be a result of the record-setting pace of the warming so far in the eastern equatorial Pacific,” Lowry said in his Eye on the Tropics blog.
The reduction in CSU’s forecast also means a lower chance that a landfalling storm will hit the U.S. The new forecast calls for an 8% chance that a major hurricane of Cat 3 or higher will make landfall along the Florida Peninsula from Jacksonville to Cedar Key. The average landfall chance is 21%.
From Cedar Key through the Panhandle, the chance has been reduced to 10%, when the average is 27%.
Kimberly Miller is a journalist for the USA TODAY NETWORK FLORIDA. She covers weather, the environment and critters as the Embracing Florida reporter. If you have news tips, please send them to kmiller@pbpost.com. You can get all of Florida’s best content directly in your inbox each weekday by signing up for the free newsletter, Florida TODAY, at palmbeachpost.com/newsletters.
This article originally appeared on Palm Beach Post: Colorado State hurricane forecast slashed with ‘beyond super’ El Niño
Reporting by Kimberly Miller, USA TODAY NETWORK – Florida / Palm Beach Post
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By Kimberly Miller, USA TODAY NETWORK – Florida | USA TODAY Network
