Hurricanes and tropical storms are no strangers to
Southern New England. Forty-one such storms have
affected the region since 1900, 12 of which made
landfall with significant impact. These 12
land-falling systems displayed similar
characteristics with respect to the storm track
for acceleration, high winds, storm surge
and heavy precipitation. This paper will review
Southern New England tropical cyclones since 1900,
focusing on the similarities of these 12
2. DATA SOURCES
Track information for each tropical cyclone was
obtained from the National Climatic Data Center
(NCDC) Historical Climatology Series 6-2 (NCDC
1993). Storm surge information was gathered through
a collection of Southern New England Hurricane
Evacuation Studies produced by the U.S. Army Corps
of Engineers. Rainfall analyses were obtained from
prior publications (Vallee 1993, Vallee and Czephya
3. CLIMATOLOGY OF THE 12 MAJOR LAND-FALLING
Table 1 shows the major tropical cyclones which
have struck Southern New England since 1900.
Twelve significant tropical cyclones impacting
Southern New England, 1900-1999. Storm intensity at
landfall is given by the Saffir/Simpson scale or TS
for tropical storm. Forward motion is at the time
of landfall (km/hr).
Tropical cyclones that impacted the region have
come from either tropical waves that matured into
tropical storms in the western Atlantic (so called
"Cape Verde" storms), or from systems
that developed in the vicinity of the Bahama
Islands. Of the 12 major land-falling systems, nine
originated from the "Cape Verde" tropical
waves, including the Great New England Hurricane of
1938 (CAT 3), while the remainder originated in the
Bahamas, including Hurricane Carol in 1954 (CAT 3).
3.1 Seasonal Distribution
Southern New England has experienced at least one
major land-falling system in each decade of the
1900s, except the 1920s. The 18 year period from
1938 to 1955 was quite active with five major
systems, including four Category 3 hurricanes. The
15 year period from 1985 to 1999 was also active
with four major systems, including two Category 2
hurricanes. Perhaps the most interesting statistic
with regard to frequency is that since 1954, there
have been no land-falling Category 3 Hurricanes.
3.2 Monthly Distribution
August and September were the most active months for
tropical cyclone activity in Southern New England,
with 10 occurrences. The remaining two occurred in
4. COMMON CHARACTERISTICS OF THE 12
LAND-FALLING TROPICAL CYCLONES
Each of these 12 systems, with varying degrees of
impact, brought high winds, coastal flooding, and
heavy precipitation to the region. Each system
experienced some degree of forward acceleration.
The core of strongest winds and the largest storm
surges were always focused east of the storm track.
The heaviest precipitation was always focused along
and west of the storm track.
4.1 Forward Motion
Each system displayed significant northward
acceleration. The average forward speed at time of
landfall was 51 km/hr, while 82 km/hr was observed
with the Great New England Hurricane of 1938.
Synoptically, one of two upper level patterns were
associated with the rapid acceleration: a deepening
long wave trough or the rapid formation of a
cut-off low in the vicinity of the Great Lakes and
Ohio Valley. The rapid acceleration enhanced high
winds, storm surge and heavy precipitation.
The rapid acceleration of these systems produced a
rather short duration of both tropical storm and
hurricane force winds, when compared to slower
moving tropical cyclones elsewhere in the western
||The average duration of tropical storm
force winds ranged from 12 to 15 hours. Hurricane force
winds were generally produced for three to six hours
centered around the time of landfall.
Systems accelerating up the coast were often
embedded in deep layer southerly flow. In the
Northern Hemisphere, the components of surface wind
and the mean flow act in the same direction,
producing enhancement (Elseberry et al. 1987).
Also, as this acceleration occurs, the eye diameter
expands, causing an eastward displacement of the
radius of maximum wind (RMW). This pattern was
observed in Hurricane Bob, with a RMW of
approximately 40 km (National Weather Service
1992), and in the Great New England Hurricane of
1938 with a RMW of over 64 km.
4.3 Storm Surge
The rapid acceleration impacts the magnitude of the
storm surge. Wind stress and pressure gradient are
the key components in surge production, with wind
stress accounting for approximately twice the surge
produced solely by pressure gradient (Anthes 1982).
The angle at which the systems made landfall in
Southern New England was generally 60 to 90
degrees, or close to perpendicular to the
coastline, aiding in surge production on
north-south oriented bays and inlets.
While the stronger tropical storms produced surges
of 0.5 to 1 m, the Category 2 and Category 3 storms
generated storm surges in excess of 4 m. For the
two most powerful storms, the Great New England
Hurricane of 1938 and Hurricane Carol, the RMW was
focused on eastern Connecticut and Narragansett
Bay. Surge modeling indicates for a storm similar
to Hurricane Carol, surges in excess 8 m will
occur on portions of Buzzards Bay (U.S. Army Corps
of Engineers 1997).
Nearly half of all tropical cyclones that impacted
Southern New England since 1900 produced
significant river and small stream flooding. Heavy
rainfall typically developed well in advance of the
storm center, in response to the dramatic increase
in moisture advection and a rapidly destabilizing
atmosphere produced by a deepening upper level
trough or cut-off low. In addition, as shown by
Vallee and Czephya (1996), strong east or southeast
inflow produced an enhancement of rainfall in
upslope regions of the major river basins in the
region. The duration and strength of this inflow
was critical to the magnitude of the enhancement.
Tropical cyclones tended to maximize both
components, thus explaining why, in spite of such a
rapid forward motion, tropical cyclones impacting
Southern New England also produced widespread
Typically, the first bands of heavy rainfall
arrived 12 to 15 hours in advance of the storm
center. The average rainfall of 150-200 mm was west
of the track of the storm, with the heaviest
amounts in orographically favored locations.
East of the storm, two inches or less was common.
Hurricane Bob, a tight Bahama-born system, produced
a dramatic rainfall distribution across Rhode
Island with a maximum of over 170 mm in the
northwest and less than 12 mm in the southeast.
Tropical Storm Diane, one of the slower moving
systems, produced 250-500 mm of rain in
orographically favored portions of the Connecticut
Major land-falling tropical cyclones in Southern
New England during the last 100 years have all
displayed similar characteristics with regard to
forward motion, distribution of wind, storm surge,
and heavy precipitation. An average forward motion
at landfall has been computed at 51 km/hr. The core
of strong winds and resulting storm surges were
focused east of the track, while rainfall was
significantly enhanced along and west of the storm
track. The consistancy in the behavoir of these
land-falling systems should allow forecasters and
emergency managers to better anticipiate and
prepare for the evolution of the storms
impact across the region.
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Evolution, Structure, and Effects
. Science Press, 208 pp.
Elseberry, R. L., W. M. Frank, G. J. Holland, J. D.
Jarrell, R. L. Southern, 1987: A Global View
of Tropical Cyclone. Office of Naval
Research, 185 pp.
National Climatic Data Center, 1993: Tropical
Cyclones of the North Atlantic, 1971-1992. NOAA
Historical Climatology Series 6-2, Asheville, NC,
National Weather Service, 1992: Disaster survey
report - Hurricane Bob August 16-20, 1991. NOAA,
U.S. Dept. of Commerce, 57 pp.
U.S. Army Corps of Engineers, New England Division,
1997: Southern Massachusetts Hurricane Evacuation
Study. USACE Technical Data Report, Waltham, MA,
Vallee, D. R., 1993: Rhode Island Hurricanes and
Tropical Storms, A Fifty-Six Year Summary
1936-1991. NOAA Tech. Memo. NWS-ER-86, Bohemia, NY,
_____, and L. Czephya, 1996: An Analysis of
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