For 15 of those 40 hours, Dorian was a Category 5 hurricane — the slowest-moving Category 5 storm on record in the North Atlantic Basin.
Most hurricanes of Dorian’s strength move at a forward speed of about 10 to 15 mph. Dorian crawled along at 1.3 mph — less than half of a typical human walking pace. At times, the hurricane was stationary.
Great Abaco Island, a slender north-south oriented island to the east of Grand Bahama, first took the brunt of Dorian’s Category 5 impact Sunday. Though Great Abaco is only about 10 miles wide where Dorian crossed, the storm rode northwest parallel to the island. That meant the eyewall was in contact with Great Abaco for a whopping 8 hours 22 minutes based on conservative radar estimates.
At that time, the National Hurricane Center issued several dire statements, warning of the potential for 220 mph wind gusts and an 18- to 23-foot ongoing storm surge, which is the storm-driven rise in ocean water above normally dry land. At that point, Dorian was moving west at 5 mph.
By the time the Category 5 monster arrived on Grand Bahama, it had slowed to a crawl. According to Philip Klotzbach, a hurricane specialist and researcher at Colorado State University, Dorian was the strongest Atlantic storm on record to venture so far north. It also tied for the dubious title of strongest hurricane wind speed at landfall in the North Atlantic Ocean Basin since records began in the late 1800s.
Think back to the devastation associated with Hurricane Michael in October 2018. That storm’s eyewall probably spun over any given area for about two hours. Now add 20 mph to the already Category 5 winds, an extra nine or 10 feet of storm surge, and hold the storm still for more than 36 hours. It’s simply unimaginable.
Upon reviewing radar data, it appears that Pelican Point on Grand Bahama Island, on the eastern side of the island, experienced a continuous 25 hours and 22 minutes (give or take a few minutes) in the eyewall. During five of those hours, the storm had winds of Category 5 intensity; Dorian was a major hurricane throughout the remaining 19-plus hours.
Pelican Point is not a highly populated community; in fact, it’s on a rural part of the island with only two dozen or fewer homes. Those residents probably endured a period of weather unlike anything in memory.
“A Cat 5 just stopping dead in its tracks over land, no, can’t think of any,” wrote Brian McNoldy, Capital Weather Gang’s tropical weather expert.
Pelican Point then saw a lull of about eight hours, during which point it was nestled in Dorian’s eye. This occurred between 12:21 a.m. and 8:25 a.m. Monday, when the eyewall returned with a vengeance as Dorian engaged the parking brake.
Can you imagine sleeping in the dead of night beneath partly cloudy skies and nearly calm winds, knowing that, within 10 or 15 miles in all directions, you were entirely surrounded by a ring of 175-plus mph fury? It’s simply unfathomable.
If you think that’s berserk, try this stat: Halls Point on Grand Bahama was in the eye for 11 hours and 43 minutes. From just before 6 a.m. Monday to 5:30 p.m., the tip of Halls Point was engulfed in Dorian’s cylindrical void.
At times, the eyewall lurked a mile or less away. Imagine being able to outwalk the eyewall. Of course, this would have been impossible — because the tornado-like wind speeds were accompanied by 18 to 23 feet of storm surge. For about an hour, from 5:30 p.m. to 6:30 p.m. Monday, Halls Point straddled this boundary, irregularities in the eyewall’s wobbly edge thrusting Halls Point in and out of extreme conditions.
Freeport, a community of about 27,000, narrowly missed the worst of the winds in the inner eyewall. In fact, radar data shows that Freeport didn’t actually make it into the eyewall. However, continuous onshore 100 mph winds stubbornly pushed an extreme surge ashore, probably causing significant damage in the popular vacation destination.
It’s not uncommon that tropical storms and hurricanes stall out. In fact, that’s relatively common, because these storms are steered by larger weather features that can sometimes be absent. But most of them at least move a little, and very few don’t stand still for this long, especially when they’re this strong.
The powerful circulation of a high-end hurricane usually interacts some with its environment even if the background airflow is weak, spurring some movement. But Dorian was a different sort of beast.
Klotzbach wrote that Dorian only tracked 25 miles in 24 hours; that would make it the slowest-moving Category 5 Atlantic hurricane on record.