a. Synoptic History
Erin formed from a tropical wave that crossed from the coast
of Africa to the tropical eastern Atlantic Ocean on 22 July 1995. A large
area of disturbed weather and two distinct low-level circulation centers
accompanied the wave. The circulation centers were oriented from northwest
to southeast and moved in tandem toward the west-northwest over the following
By the 27th, both circulations were generating deep convection
a few hundred miles to the northeast of the Leeward Islands. A day later,
meteorologists at the NHC Tropical Analysis and Forecast Branch (TAFB,
formerly TSAF as in figures) and the NESDIS Synoptic Analysis Branch (SAB)
assigned Dvorak technique T-numbers of 1.5 to the trailing cloud cluster.
These numbers increased to T-2.5, potentially indicative of a tropical
cyclone with 40 mph (tropical storm force) winds
by midday on the 30th. In reality, although the cloud pattern was slowly
consolidating and surface pressures were falling ahead of the system in
the Bahamas, development was retarded by southwesterly vertical wind shear
associated with an upper-level low that was moving southwestward at 12-17
mph across Florida. Reconnaissance aircraft data from the U.S. Air Force
Reserves (Hurricane Hunters) on the 28th, 29th, and again during midday
on the 30th indicated that the system did not have a closed circulation
at low levels. Instead it was a very vigorous tropical wave--winds speeds
around 46 mph were reported from ships in the
northern part of the cloud pattern.
Because of the system's potential for development and its close
proximity to the Bahamas and Florida, a special nighttime reconnaissance
mission was requested by the NHC and flown by the Hurricane Hunters late
on the 30th. The first "vortex message" was transmitted to the NHC shortly
after 0100 UTC on the 31st. From that information it is estimated that
the system became Tropical Storm Erin at 0000 UTC on the 31st.
The upper-level low near Florida affected Erin's movement and
development. Associated steering currents accelerated Erin from 6 to 17
mph and diverted the cyclone around the northeast side of the low. The
temporary and fairly subtle change of heading from west-northwest to northwest
might have been insignificant if Erin had not been so close to land. Instead,
the track of the center was deflected to a course that was over or near
much of the Bahama Island chain and then toward a landfall over east-central
(rather than southeast) Florida. As this occurred, enough shearing persisted
to permit only slow strengthening. On the evening of the 31st, Erin became
a hurricane while centered near Rum Cay in the Bahamas. A ragged-looking
eye appeared on satellite pictures on August 1st. Erin made landfall around
0600 UTC on the 2nd near Vero Beach, Florida as a Category 1 hurricane
on the Saffir/Simpson Hurricane Scale, with estimated maximum 1-minute
wind speeds of 86 mph.
Erin's track bent back to west-northwest while the cyclone
crossed the Florida peninsula during the morning and early afternoon of
the 2nd. The cyclone weakened to a tropical storm with 58-mph winds during that period, but remained well-organized.
Upon emerging into the eastern Gulf of Mexico, Erin reintensified on a
track that gradually swung back to northwestward at about 10 knots. Final
landfall occurred near Pensacola, Florida during the late morning of the
3rd. An eye had redeveloped but upper-level outflow was not particularly
impressive on satellite images. Erin had around 98 mph
winds (Category 2) in a small area of its northeastern eyewall when that
part of the hurricane came ashore near Fort Walton Beach in the western
Erin weakened to a tropical storm in southeastern Mississippi
overnight on the 3rd/4th. It was a tropical depression when its track
shifted to the north on the 5th and the east on the 6th. The depression
merged with a frontal system over West Virginia on the 6th.
b. Meteorological Statistics
Several reports of hurricane force winds (WMO-standard 10-
minute average) were received from the Bahamas, including 78 and 81 mph during the passage of the northeast part
of the eyewall over Cat Island at 0200 UTC and 0400 UTC, respectively,
on August 1st. These 10-min winds are about 80 percent of the 99
mph maximum 10-second 850 mb flight-level winds encountered by
the reconnaissance aircraft. Several amateur radio reports included gusts
to around 104 mph in the Bahamas. The ship Tampa
was in the northeastern eyewall at 1200 UTC on the 1st when it reported
81 mph winds.
The basis for the 86-mph wind speed
estimate along the Florida east coast was a 1-minute wind speed of 86
mph recorded by a Florida Institute of Technology anemometer which
made one observation per hour at Sebastian Inlet. This wind appears to
coincide with the passage of one of Erin's strongest convective cells
at that time (0500 UTC), which was located in the northwestern eyewall.
While somewhat higher winds could have been expected to occur offshore
in the (normally stronger) northeastern eyewall, Doppler radar data for
that area suggests that the peak winds (inbound toward Melbourne) at the
lowest tilt angle were only slightly stronger, around 98
mph. The maximum 850 mb flight-level wind speed then was around
A wind speed of 98 mph is estimated
at 1330 UTC on 3 August near Fort Walton Beach. This took place in a small
area within Erin's strongest sector, the northeastern eyewall, as it swept
across the shoreline. That estimate is based largely on NWS Mobile office
Doppler wind data which showed inbound wind speeds exceeding 115
mph in a few volume samples centered at about 9,800 feet above
the coast from 1320 to 1400 UTC. The peak 850 mb flight-level wind speed
leading up to this time was 106 mph in the northeastern
eyewall near 1200 UTC, but subsequent excursions into that part of the
hurricane were precluded by the hurricane's close proximity to land.
Doppler velocities decreased by about 17 mph over the following
two hours and 86 mph is the estimated maximum
surface wind speed when the center of the eye came ashore around 1600
UTC. Hence, the coastal region immediately west of Fort Walton Beach,
including Pensacola, experienced Category 1 conditions, though gusts to
near 115 mph likely occurred. The FAA system of
six anemometers at Pensacola Regional Airport (PNS) registered a maximum
30-second wind speed of about 69 mph. The highest wind speed measured at an official
reporting station in the Florida panhandle was an 101-mph gust at the Pensacola Naval Air Station (NPA).
Amateur radio operators relayed unofficial observations of gusts near
109 mph to the NHC.
The hurricane's lowest pressure of 973 mb was reported by the
Hurricane Hunters near 1330 UTC and again near 1600 UTC on the 3rd. The
latter measurement placed the center of Erin near the coast and in the
southern part of the eye as seen on surface radar.
1. Storm Surge Data
The Melbourne National Weather Service Office estimated that
Erin generated a 2 to 4 foot storm tide during the Florida east coast
landfall. Storm tides averaged 1 to 2 feet along the west- central Florida
2. Rainfall Data
According to the Melbourne office, up to about 12 inches
of rain fell southwest through northwest of their site.
Several small, brief tornadoes occurred over east- central
Florida well after Erin made landfall. One tornado caused minor damage
in Titusville. Another occurred near Lake Lizzie, killing two horses.
A couple of weak tornadoes were also reported over northeast Florida and
in the panhandle near Hurlburt Air Force Base.
c. Casualty and Damage Statistics
There were 6 deaths attributed to Erin; 6 in Florida.
All Bahamas islands from Mayaguana to Grand Bahama suffered
damage characterized by the Bahamas Department of Meteorology as mostly
minor. Some structural damage, sunken boats, crop loss and flooding was
reported. Losses known to date for Abaco, Grand Bahama, Mayaguana, and
Exuma total $400,000.
The American Insurance Services Group estimated $375
Million as the loss to insured property in the United States caused
by Erin ($350 Million in Florida, $20
Million in Alabama, and $5 Million
in Mississippi). Because the total loss is usually estimated by the NHC
to be up to about double the insured loss, the total U.S. loss is tentatively
estimated at $700 Million.
Wind damage occurred over east-central and northeast Florida.
Thousands of homes and businesses suffered damage in Brevard county. Less
significant damage occurred in other counties in the region. Freshwater
flooding from rainfall occurred in the Melbourne and Palm Bay areas and
westward in some spots to the Florida gulf coast. Beach erosion occurred
along the central Florida east coast, with damage mainly to boardwalks,
beach accessways and the dune system. Light to moderate beach erosion
was also reported northward to the Georgia border. Minor erosion occurred
along the west-central Florida coast.
The most significant structural damage for the final landfall
occurred on Pensacola Beach, Navarre Beach, around Mary Esther and in
northeast Pensacola. More than 2,000 homes were damaged there and crop
losses were reported. Some beach erosion was reported west of Navarre
Beach. Farther inland, about 100 homes were damaged in Alabama. Widespread
tree, power line and crop damage extended inland.
Maximum Intensity For Hurricane Erin