Tropical storm update: What NC forecasters say about possible hurricanes in the Atlantic

Three weather systems — an upper-level low, Tropical Storm Bret and a still-developing disturbance behind it in the Atlantic Ocean — could affect North Carolina weather over the next couple of weeks.

First, this week’s forecast. The National Weather Service says that an upper-level low — a swirling pool of comparatively cold air high in the atmosphere — will generate heavy rain across the Southeastern U.S. this week, including most of North Carolina.

Up to 6 inches of rain is expected in some areas of the state through Friday, enough to cause flooding and tree-falls due to saturated soils.

Wake, Durham, Orange, Chatham and Johnston counties are under a flood advisory.

Tropical Storm Bret: Timeline for US, NC

Meanwhile, the National Hurricane Center declared Bret a tropical storm at 5 p.m. Monday, making it the second of the 2023 season and one of the earliest on record for the region where it developed, which doesn’t usually begin to churn out storms until August.

The National Oceanic and Atmospheric Administration, which tracks tropical storms, said early Wednesday that Bret is still expected to strengthen as it moves west across the Atlantic toward the Lesser Antilles, Puerto Rico and the Virgin Islands.

Bret will cross the islands Thursday afternoon and Thursday night, NOAA said, as a strong tropical storm with heavy rains, strong winds and dangerous waves along the coast. A tropical storm watch is in effect for Barbados, Dominica, Martinique and St. Lucia. Additional watches in the region are expected today.

An area of high pressure over the central Atlantic should keep Bret from moving north toward the U.S., forecasters said, and though warm ocean temperatures could feed the storm as it moves across the Atlantic, it’s also facing wind-shear effects that will likely suppress it.

If it were to grow into a hurricane, it would be first June hurricane since 2012, forecasters said. However, it’s expected to weaken as it moves into the Caribbean Sea and degenerate into a tropical wave by the time it reaches the western Caribbean.

Jonathan Blaes, meteorologist-in-charge at the National Weather Service in Raleigh, said Tuesday Bret is expected to pass just south of Haiti and the Dominican Republic on Saturday and then move into the Caribbean.

While it can’t be ruled out, he said, “it appears quite unlikely” that Bret would have a direct impact on North Carolina.

Third tropical disturbance: ‘A wake-up call’

Weather watchers already have their eyes on another disturbance developing in the Atlantic to the east of Bret.

The National Weather Service says showers and thunderstorms in the area suggest a tropical wave is organizing several hundred miles southwest of the Cabo Verde Islands, and forecasters say conditions are good for the system to develop further over the next couple of days.

An update on Wednesday morning indicated the disturbance had become better organized overnight and is expected to move west-northwest over the central Atlantic through Saturday.

The weather service says the likelihood of that disturbance becoming a tropical storm is 80 percent over the next week.

Forecasters say that storm, if it develops, would be called Cindy, but they can’t say yet whether it would affect North Carolina or the rest of the U.S. east coast. Because the disturbance is farther south than Bret, Blaes said he would not expect it to affect our state either.

“But it’s a wake-up call,” Blaes said, to have two possible storms develop so early. “It’s an opportunity for folks to think about what they would do if a system were to develop, so we can prepare and get ready for the hurricane season.”

Storm predictions this season will be a challenge

Two competing forces at work this summer may make it challenging to predict how many storms will develop into Atlantic hurricanes and what threat they could pose to North Carolina and the rest of the U.S. east coast.

Warmer-than-normal water temperatures in the Atlantic such as those reported now generally increase the risk of tropical storms and hurricanes. But the development of an El Niño this month is expected to help suppress the development of severe tropical storms.

The National Weather Service has said its forecasters expect to see 12 to 17 named storms in the Atlantic this season, which runs June 1 through Nov. 30. Five to 9 are expected to become hurricanes and one to four are expected to become major hurricanes of Category 3 or above. North Carolina and the rest of the east coast has a slightly elevated chance to see above-average rainfall this summer.

Over the past 10 years, according to the National Oceanic and Atmospheric Administration, flooding from excessive rainfall was the single deadliest hazard in tropical storms.