Atlantic may bear more hurricanes that could threaten US, Caribbean through November
Including Ophelia, there have been 15 tropical storms, 10 hurricanes and five major hurricanes so far in the 2017 Atlantic season.
“Since the satellite era began during the early 1960s, 2017 is the only year where there have been 10 consecutive hurricanes in the Atlantic basin,” according to AccuWeather Hurricane Expert Dan Kottlowski.
As warmth persists over much of the southern and eastern United States this month, so too will the potential for additional tropical storms and hurricanes to form and track near populated areas.
During most years, around this point in October, atmospheric conditions begin to change near North America that tend to inhibit tropical storm formation and/or keeps tropical storms away.
However, the overall atmospheric environment will remain favorable for tropical storm formation for weeks this year.
Tropical and subtropical waters are still warm and winds aloft are rather weak in the key development areas, according to Kottlowski.
“I think there will be at least two more tropical storms, of which one or two can become a hurricane into December,” Kottlowski said.
“There is still a chance of one more major (Category 3) hurricane.”
This is not to say that all or any of these will strike land in the U.S., Caribbean or anywhere, but the risk is there.
Aside from an occasional mid-ocean storm, the typical tropical storm formation areas during the rest of October and November are farther west than during August and September.
Since most tropical storms form in the Caribbean, near Central America and the southern coast of the U.S., it is nearly impossible for such a storm to avoid hitting land or at least avoid causing indirect impact.
This year, an area of high pressure off the southeastern Atlantic coast will persist. A high pressure area is a large zone of sinking air that rotates clockwise. The flow around this high is what is helping to pump temperatures in the southern and eastern U.S. and provide an avenue for tropical systems to travel upon.
As of Friday, Ophelia was churning over the open waters of the Atlantic as a Category 2 hurricane.
Ophelia may pass close enough to the Azores to bring rough seas, rain and gusty winds to the islands this weekend. Ophelia is then expected to lose its tropical characteristics but still batter Ireland and the United Kingdom with powerful winds and downpours early next week.
In the short term, Ophelia isn’t the only area of concern in the Atlantic.
“A strong tropical system centered a few hundred miles east of the Leeward Islands is being watched for possible development late in the upcoming weekend or early next week,” Kottlowski said.
Kottlowski anticipates that the only landmass that would see direct impacts from this system if it does develop would be Bermuda.
A cold front set to sweep through the eastern U.S. Sunday into Monday will keep the system from threatening the U.S.
However, the system is expected to enhance shower activity across the Lesser Antilles and to Puerto Rico this weekend and into early next week.
There have been isolated incidents of flash flooding across these Caribbean islands, since much of the landscape has been stripped of foliage by Maria and Irma.
Debris littering streets and clogging drains led to flooding in San Juan, Puerto Rico, last weekend as rain poured down. This occurred as residents grapple with Maria’s aftermath, and 40 percent of Puerto Ricans do not have drinkable water, according to CBS News.
Another area to watch will be just off the southeastern U.S. coast later next week.
There have been destructive hurricanes during late October and November. These include Category 5 Hurricane Mitch (1998) and Category 2 Hurricane Sandy (2012).
By Jordan Root, Meteorologist for AccuWeather.com