NWS: Bermuda High and El Nino Pushing Most Storms Away from North America
Florida - Monday October 23, 2023: Of the 12 tropical storms and 7 hurricanes that have formed in the Atlantic Basin this season only four have made landfall on the North American Coast.
1. Way back in January an unmade system slipped between Nova Scotia and Newfoundland, only later to be upgraded into a Subtropical Storm.
2. In August Hurricane Idalia came out of the Gulf and cut through northern Florida.
3. In early September Lee former and became a major hurricane that tracked north into Maine and Nova Scotia.
4. Later that same month, Ophelia began forming northeast of the Bahamas and came ashore as a strong tropical storm in North Carolina.
None of the 10 other tropical storms and 5 hurricanes that have formed in the Atlantic Basin this season made land fall in North America.
National Weather Service Warning Coordination Meteorologist Will Ulrich says the Bermuda High has helped push most of them away.
“The Bermuda High is basically a permanent area of high pressure throughout the course of the summer," said Ulrich, "and depending on where exactly it is, it really is the thing that steers tropical cyclones in the Atlantic Ocean.”
When the Bermuda High pressure area is closer to the east coast, storms have a better chance of making land fall. “This year we’ve seen the high-pressure migrant a little bit further out into the open Atlantic. So, when that high pressure pulls away from the east coast of the United States, it basically opens up a path for those tropical cyclones to move northward away from the state of Florida. So, that’s what we’ve been seeing a lot of this year.”
The EL Nino weather pattern that has developed this year has also helped, said Ulrich. “El Nino has enhanced the amount of wind shear that we’ve seen this year in the Gulf of Mexico and the Caribbean, because wind shear is one of those things that tears tropical cyclones apart.”
However, Ulrich notes that Idalia this year, and Ian last year remind us to watch what comes out of the Gulf as well. “The storms that have impacted Florida don’t just come at us from the east. We have to look for tropical cyclones from any direction of the east to the west from any direction throughout the course of the year.”