Dorian: Wind

The 7AM Update from the National Hurricane Center:

Hurricane Dorian Tropical Cyclone Update
NWS National Hurricane Center Miami FL       AL052019
700 AM EDT Fri Sep 06 2019

...EYEWALL OF DORIAN CONTINES TO MOVE ACROSS THE OUTER BANKS
OF NORTH CAROLINA...

A Weatherflow station at Ocracoke, North Carolina, recently
reported a sustained wind of 69 mph (111 km/h) and a wind gust of
89 mph (120 km/h).  Cape Hatteras recently reported sustained winds
of 52 mph (83 km/h) and a wind gust of 66 mph (106 km/h).
SUMMARY OF 700 AM EDT...1100 UTC...INFORMATION
----------------------------------------------
LOCATION...35.0N 76.0W
ABOUT 30 MI...50 KM WSW OF CAPE HATTERAS NORTH CAROLINA
ABOUT 40 MI...65 KM NE OF CAPE LOOKOUT NORTH CAROLINA
MAXIMUM SUSTAINED WINDS...90 MPH...150 KM/H
PRESENT MOVEMENT...NE OR 50 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...956 MB...28.23 INCHES

The official 5AM advisory from the NHC takes the center of Dorian to a position of 38.8N and 69.9W – just south of the “40/70 Benchmark”. That position would be about 170 miles south of Chatham…certainly a safe distance to keep the core of hurricane force winds well out to sea.

As mentioned yesterday, the size of the storm’s wind field has expanded (and will continue to grow) and a pass within 200 miles is likely going to be close enough to yield a period of gusty east, northeast and then northerly winds. As an example, this morning, coastal locations along the Delmarva Peninsula – between 150 and 180 miles north of the center of Dorian – are gusting to about 40 mph. Areas in Southeast Virginia about 100 to 120 miles from the center are gusting over 50 mph.

Winds of a similar magnitude – gusts on the order of 35 to 50 mph – are a pretty safe bet here on the Cape later tonight and into Saturday morning…which would be enough to bring down some branches and limbs and may result in a few pockets of power outages or brief power disruptions. There is still a window of time (4 to 6 hours between about 6AM and Noon Saturday) when winds will shift to the north as Dorian pulls away that could bring us some stronger wind gusts. Given the near-shore waters are very mild (over 70F in most locations), the low-levels of the atmosphere may prove more conducive to mixing down some stronger gusts from aloft than we would normally expect…which may allow a ribbon of 50-55 knot winds passing overhead to briefly mix to the surface. The result would be some 50 to 60 mph northerly wind gusts, which would enhance the threat for some downed limbs and branches and likely even bring down a few trees here and there.

Post a Comment

Your email address will not be published. Required fields are marked *