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1996 PRELIMINARY
REPORTS |
Fran was a Cape Verde hurricane that moved across the Atlantic during the peak of the hurricane season. It made landfall on the North Carolina coast as a category three hurricane on the Saffir/Simpson Hurricane Scale, resulting in significant storm surge flooding on the North Carolina coast, widespread wind damage over North Carolina and Virginia, and extensive flooding from the Carolinas to Pennsylvania. a. Synoptic HistoryHurricane Fran formed from a tropical wave that emerged from
the west coast of Africa on 22 August. Deep convection associated with
the wave was organized in a banding-type pattern and animation of satellite
images suggested a cyclonic circulation. Ship reports soon confirmed that
the circulation was on the surface. The tropical depression moved westward near 17 mph for the
next few days without significant development. This lack of development
may be attributed, in part, to disrupted low-level inflow due to the large
and powerful Hurricane Edouard which was
centered about 750 nautical miles to the west-northwest. Satellite intensity
estimates suggest that the depression became Tropical Storm Fran at 1200
UTC 27 August while located about 900 nautical miles east of the Lesser
Antilles. Fran began to track toward the west-northwest in the wake
of Hurricane Edouard. Deep convection became
more concentrated and Fran is estimated to have reached hurricane status
at 0000 UTC 29 August while centered about 400 nautical miles east of
the Leeward Islands. The center of Fran was about 150 nautical miles to
the northeast of the Leeward Islands near 1200 UTC 30 August. The tropical cyclone weakened to just below hurricane strength
later on the 30th, possibly due to the low-level inflow being disrupted
again by Edouard. About this time, changing
steering currents caused Fran to turn toward the northwest and slow to
about 6 mph. By 1200 UTC 31 August, as Edouard
moved farther away, Fran had regained hurricane strength. As Hurricane
Edouard moved northward off the U.S. mid-Atlantic coast, the subtropical
ridge became better established to the north of Fran, causing Fran to
resume a west-northwestward motion with an increased forward speed of
about 12 mph. Fran moved on a track roughly parallel to the Bahama Islands
with the eye remaining a little more than 100 nautical miles to the northeast
of the islands. Fran strengthened to a category three hurricane by the time
it was northeast of the central Bahamas on 4 September. The powerful tropical
cyclone began to be influenced by a cyclonic circulation centered over
Tennessee that was most pronounced inautical milesd to upper levels of
the atmosphere. Fran was steered by the resulting flow around the low
over Tennessee and the western extension of the subtropical ridge over
the northwest Atlantic. The hurricane gradually turned toward the northwest
to north- northwest and increased in forward speed. The minimum central pressure dropped to 946 mb and maximum
sustained surface winds reached 121 mph, Fran's peak intensity, near 0000
UTC 5 September when the hurricane was centered about 250 nautical miles
east of the Florida east coast. Fran was moving northward near 17 mph when it made landfall
on the North Carolina coast. The center moved over the Cape Fear area
around 0030 UTC 6 September, but the circulation and radius of maximum
winds were large and hurricane force winds likely extended over much of
the North Carolina coastal areas of Brunswick, New Hanover, Pender, Onslow
and Carteret counties. At landfall, the minimum central pressure is estimated
at 954 mb and the maximum sustained surface winds are estimated at 115
mph. The strongest winds likely occurred in streaks within the deep convective
areas north and northeast of the center. Fran weakened to a tropical storm while centered over central
North Carolina and subsequently to a tropical depression while moving
through Virginia. The tropical cyclone gradually lost its warm core as
it moved over the eastern Great Lakes and became extratropical near 0000
UTC 9 September while centered over southern Ontario. The remnants of
Fran were absorbed into a frontal system near 0600 UTC 10 September. b. Meteorological StatisticsAll operational aircraft reconnaissance flights into Fran
were provided by the U.S. Air Force Reserves. These "Hurricane Hunters"
made 71 center fixes during 17 flights. The minimum central pressure reported
by aircraft was 946 mb at 2306 UTC 4 September. A circular eye with a
diameter of 25 nautical miles was observed on aircraft radar at this time.
The 946 mb minimum pressure was measured by dropsonde and was the lowest
pressure reported during Fran's existence. The maximum winds of 131 mph
from a flight level of 700 mb (near 10,000 feet) were measured about 6
hours prior to the 946 mb pressure report. Flight-level winds in excess
of 115 mph were reported several times during the two days prior to landfall.
130-mph winds were reported from aircraft 52 nautical miles east of the
hurricane center at 2314 UTC 5 September, and 123-mph winds were reported
41 nautical miles northeast of the center at the time of landfall. However,
the core of the hurricane weakened somewhat on radar presentations, and
a closed eyewall was not reported by aircraft during the two hours prior
to the center moving onshore. Objective intensity estimates from digital infrared satellite
imagery peaked near the time that the minimum central pressure was reported
by reconnaissance aircraft. The WSR-88D (Weather Surveillance Radar - 1988 Doppler) at
Wilmington, North Carolina, measured winds in excess of 138 mph aloft
as the inner convective bands approached the Cape Fear area at 2130 UTC
5 September. A ship with call sign LAVX4 reported 98 mph winds
and a pressure of 984 mb at 1800 UTC 5 September while located about 60
nautical miles northeast of the hurricane center. Several other ship reports
were helpful in defining the extent of tropical storm force winds, as
were reports from a network of drifting buoys deployed offshore of the
Carolinas in advance of Fran. Table 2 lists ship reports of at least tropical
storm force winds in the vicinity of Fran. Several wind gusts to hurricane force were measured from
coastal areas in North Carolina. As usual for landfalling hurricanes,
however, reports of sustained hurricane force winds are difficult to find.
Table 3 lists selected U.S. surface observations. The NOAA C-MAN station
at Frying Pan Shoals (about 50 nautical miles south-southeast of Wilmington,
North Carolina) reported sustained winds of 91 mph and gusts to 124 mph
from a tower about 80 feet above sea level. Numerous pressure and wind reports from North Carolina were
relayed to the NHC through amateur radio volunteers. The lowest measured
pressure was 954 mb from Southport. The highest measured wind gust was
137 mph at an elevation of 30 feet (mounted on a house approximately 4
feet above the chimney) from a Davis wind instrument located on Hewletts
Creek in Wilmington. A gust to 125 mph was measured in Wrightsville Beach.
Although these measurements are very much desired to supplement the more
official observations, they will not be listed in Table 3 until their
accuracy is verified. 1. Storm SurgeAt the time of this report, a post-storm high water mark survey was being conducted by the U.S. Army Corps of Engineers and the U.S. Geological Survey. Many high water marks remain to be surveyed and "tied into" bench marks. The locations of the maximum values cannot be finalized until the survey is complete. However, initial survey results show an extensive storm surge along the North Carolina coast primarily southwest of Cape Lookout. Still water mark elevations on the inside of buildings, indicative of the storm surge, range from 8 to 12 feet. Outside water marks on buildings or debris lines are higher due to the effect of breaking waves.2. Rainfall DataRainfall totals exceeding six inches were common near the path of Fran. WSR-88D radar precipitation estimates were as high as 12 inches over portions of Brunswick and Pender counties in North Carolina. Extensive flooding spread well inland from the Carolinas into Virginia, West Virginia and Pennsylvania. Some of this flooding was considered the most severe in years. Near Washington, D.C., for example, the Old Town district of historic Alexandria was partially evacuated as the Potomac River rose, flooding streets with more than three feet of water. The next update of this report will include an analysis of rainfall along the path of Fran to be provided by the NWS Eastern Region Headquarters.3. TornadoesSeveral tornadoes were indicated by Doppler radar in North Carolina and Virginia. Confirmation, however, has been difficult due to the extensive nature of straight line wind damage across the region.c. Casualty and Damage StatisticsThere were 34 deaths attributed to Fran. Storm surge on the North Carolina coast destroyed or seriously
damaged numerous beachfront houses. Widespread wind damage to trees and
roofs, as well as downed power lines, occurred as Fran moved inland over
North Carolina and Virginia. Extensive flooding was responsible for additional
damage in the Carolinas, Virginia, West Virginia, Maryland, Ohio and Pennsylvania. Nearly a half-million tourists and residents were ordered
to evacuate the coast in North and South Carolina. Press reports from
Reuters News Service stated that 4.5 million people in the Carolinas and
Virginia were left without power. The Property Claim Services Division of the American Insurance Services Group reports that Fran caused an estimated $1.6 Billion in insured property damage to the United States. This estimate includes $1.275 Billion in North Carolina, $20 Million in South Carolina, $175 Million in Virginia, $50 Million in Maryland, $20 Million in West Virginia, $40 Million in Pennsylvania and $20 Million in Ohio. A conservative ratio between total damage and insured property damage, compared to past landfalling hurricanes, is two to one. Therefore, the total U.S. damage estimate is $3.2 Billion.
Maximum Intensity For Hurricane Fran
Landfall for
Hurricane Fran
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