April 16, 2007 High Wind Event
Updated 2007/04/20
Event Headlines
...Wind gusts in excess of 45 MPH were reported across most of the state with gusts
in excess of 55 MPH reported across a large portion of the Mountains and Northern
Piedmont...
...During the height of the storm on Monday afternoon, there were more
than 200,000 customers without power across North Carolina...
...According to media reports, over 300 reports of downed trees and power lines were made in Wake County with nearly a 100 made in the city of Durham...
Event Overview
An unseasonably strong nor’easter rapidly developed off
the North Carolina coast late on Sunday, April 15, 2007.
The surface low had already strengthened to 990 MB
over northwest North Carolina by 18Z/15 (200 PM EDT Sunday). Due to
the unusual southerly track and strength of the 500 MB low
across the Tennessee Valley and North Carolina, the surface
low continued to deepen as it moved east across
northern North Carolina late Sunday and Sunday night,
reaching 983 MB near the Chesapeake Bay region by 00Z/16 (800 PM EDT Sunday).
The low pressure system rapidly intensified into a strong damaging
nor’easter as it moved up the eastern seaboard and became
nearly stationary around New York City on Monday.
At 12Z/16 (800 AM EDT Monday) the
storm was centered over New York City with a pressure of 969 MB. The storm slowly weakened
and drifted eastward Monday night and Tuesday.
Several factors led to the damaging wind event including a
very tight surface pressure gradient and 70 to 80 KT wind maximum
at 850 MB. In addition, a strong 500 MB rise/fall couplet was observed
(310 meter falls over Upton NY (OKZ) / 190 meter
rise over Atlanta, GA (FFC) at 12Z/16). The strongest
winds across central North Carolina peaked during the mid morning to mid afternoon hours
with surface heating and convective mixing allowing stronger winds aloft to reach the surface.
The winds continued to produce damage well into the night over the elevated
terrain of western North Carolina.
The storm system had a variety of impacts on North Carolina as it
produced several days of very active weather.
There were numerous severe thunderstorms on Sunday as
the surface and upper level low pressure systems moved across the
state. Heavy rain also affected portions of the Piedmont where some areas totaled between 2
and 4 inches producing minor flooding of streams and some
main stem rivers.
However, the most widespread impact across the state came on the
back side of the rapidly intensifying nor’easter on Monday. Strong gradient winds buffeted North
Carolina with
northwest winds gusting between
45 and 62 mph over the Piedmont to the coast. The winds
were stronger over the Mountains and Foothills where wind
gusts to between 60 and 80 mph were common.
These winds were strong enough to prompt High Wind Warnings
from the Mountains eastward across the Piedmont into the
Coastal Plain. There were countless trees downed by the
winds with the Mountains, Foothills, and Piedmont especially
hard hit. During the height of the storm on Monday afternoon, there were more
than 200,000 customers without power across North Carolina.
Trees fell on houses, vehicles, and in some cases across
highways. One large tree even fell into the southbound
lanes of I-85 near Oxford blocking both lanes of the busy
interstate for several hours. The cities of Chapel Hill,
Durham, Raleigh, Greensboro, Winston-Salem, and Burlington
reported many trees downed, with numerous reports that
they had fallen onto houses and vehicles. Several people
narrowly escaped injury from the falling trees.
Maximum Wind Gust Map
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