Two weeks ahead of the official start of Atlantic hurricane season, Tropical Storm Arthur scraped the North Carolina Outer Banks on Monday morning, bringing torrential rainfall, gusty winds, rough surf and coastal flooding.

Nearly half a foot of rain had come down by early Monday, an amount that could swell as additional rain squalls pivot across the region into the afternoon. Tropical storm warnings remain in effect for coastal sections of North Carolina.

Packing maximum sustained winds of 50 mph at 11 a.m., Arthur was centered 20 miles east-southeast of Cape Hatteras, very close to making landfall. However, heading north-northeast at 16 mph, the storm is likely to remain just offshore.

After struggling to get organized and look the part on Sunday, Arthur intensified into a healthy cyclone overnight into early Monday. As of sunrise Eastern time, the system’s heaviest downpours were soaking areas between Virginia Beach and just west of Ocracoke.

Once it’s finished breezing through the coastal Carolinas, Arthur’s recurving track will swing it out to sea. But it won’t be done impacting land masses — Bermuda looks to be next in play.

Heavy downpours soaking the Outer Banks

Tropical storm warnings were up from Surf City to Duck, N.C., including for places such as Morehead City, Columbia and Nags Head. Pamlico and Albemarle Sounds were blanketed under the alert as well.

Arthur’s maximum sustained winds up to 50 mph Monday were found primarily offshore and northeast of the center.

Over land, Arthur is principally a rainmaker, but it is doing its job well — between 5 and 6 inches had already been reported along the barrier islands to kick off the workweek.

Due to Arthur’s relatively compact size, rainfall amounts have varied significantly over short distances. Barely a tenth of inch of rain had been measured inland about 70 miles from the coast.

An additional 2 to 4 inches were likely by the time the rain was set to wrap up southwest to northeast by midafternoon.

Winds largely remain offshore, but seaside concerns remain

Winds were not anticipated to be of significant concern on land with Arthur due to its path. Even Hatteras’s Mitchell Field, closest to Arthur’s core of breezier winds, measured wind gusts only up to 26 mph overnight.

Nearly an inch of rain came down in a single hour with that particular feeder band shortly before 5 a.m.

The winds were stronger offshore, though, contributing to large breaking waves that the National Weather Service estimated could approach 6 to 9 feet near the shoreline. Away from the coast, wave heights nearing 10 to 15 feet could pose a danger to mariners.

Up to 1 to 2 feet of coastal inundation was also expected in the typically prone spots of Pamlico Sound, the Neuse and Pamlico rivers and along the Albemarle Sound. Rip currents were likely as well.

There was even some overnight concern about a possible tornado threat from one of the feeder bands that pivoted across the Outer Banks, and the National Weather Service Storm Prediction Center highlighted the region in an overnight bulletin. However, the threat was deemed to be low and has since dwindled.

What’s next for Arthur

Arthur will draw away from the coastal United States late Monday afternoon, bringing dreary skies, light rain showers and a few pockets of light wind to the southern Delmarva Peninsula as it continues to drift out to sea.

Thereafter, it’s likely to orbit around an area of high pressure, and it could approach Bermuda from the north by Thursday.

By then, Arthur will probably transition to a subtropical cyclone, according to the National Hurricane Center, removed from the Gulf Stream’s heating and deriving more of its energy from mid-latitude processes that involve the jet stream.

Arthur in historical context

When Arthur was named Saturday night, it became the sixth tropical or subtropical storm to develop before the June 1 start of the Atlantic hurricane season in the last six years and the eighth preseason storm to form in the last decade.

Technically, the National Weather Service defines hurricane season’s start as landing on June 1, but a noted uptick in early-season storms — likely due to warming waters fueled by climate change — has been observed in recent years.

Coincidentally, the previous iteration of “Arthur,” which occurred in 2014, became the earliest known hurricane to make landfall in North Carolina when it struck at Category 2 strength near Shakleford Banks on July 3.

That system interacted with a cold front to produce very heavy rainfall even up into New England, including 9.15 inches that fell near the Cape Cod Canal on July 4.

The storm track of the 2020 iteration of Arthur shares an eerily similar path with the July 2014 version and two other Arthurs that flirted with the North Carolina coast in July 2002 and June 1996.

Storm names are repeated on a six-year cycle, unless they are retired for causing large amounts of destruction and/or significant loss of life.