Mary D. Stampone
Department of Geography
New Hampshire State Climate Office
University of New Hampshire
Presentation to the Plymouth State University
Environmental Science & Policy Colloquium.
Reference:
Stampone M.D. (2012) New England Tornado Hazard: Climatology and Risk – Plymouth State University Environmental Science Colloquium, Plymouth, NH, September 19, 2012
Incoming and Outgoing Shipments in 3 STEPS Using Odoo 17
"New England Tornado Hazard: Climatology and Risk" by MD Stampone
1. New England Tornado Hazard
Regional Climatology & Risk
Mary D. Stampone
Department of Geography
New Hampshire State Climate Office
University of New Hampshire
Presentation for the
Plymouth State University
Environmental Science & Policy Colloquium
September 19, 2012
3. National Tornado Statistics
Record Tornado
New Hampshire
July 28, 2008
http://www.erh.noaa.gov/gyx/
Just before noon, a
tornado touched down
near Deerfield, NH.
This tornado cut a 50 mile
path over 80 minutes to
the Maine border
4. New England Tornadoes
New England
Tornado
Influences
Lewis (2007)
Public
misconceptions
about tornado
influences
strengthen belief
that “tornadoes do
not happen here.”
Tornado Origins
(1981-2010)
6. New England Tornadoes
http://www.erh.noaa.gov/box/
A supercell thunderstorm
produced three
tornadoes including an
EF3 tornado that
traveled 39 miles from
Westfield to Charlton, MA.
Tornado Outbreak
Springfield, MA
June 1, 2011
http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=50854
9. New England Tornado Climatology
New England
Tornado
Climatology
(1951-2010)
http://www.spc.noaa.gov/wcm/#data
A lack of consistency
in older tornado
reports reduces
confidence in the
accuracy of the
data.0
20
40
60
80
100
120
140
1951-60 1961-70 1971-80 1981-90 1991-00 2001-10
TotalTornadoReports
Decade
CT MA ME NH RI VT
*
*RI - No reports prior to 1971.
*
10. New England Tornado Climatology
New Hampshire
Tornado
Climatology
(1951-2010)
http://www.spc.noaa.gov/wcm/#data
An unusually high
number of
tornado reports
from 1961 to
1973.
0
5
10
15
20
25
30
35
40
1951-60 1961-70 1971-80 1981-90 1991-00 2001-10
TotalNumberofEvents
Unknown F0 F1 F2 F3 F4 F5
11. CT MA ME NH RI VT
New England Tornado Climatology
New England Tornado
Climatology
(1981-2010)
http://www.spc.noaa.gov/wcm/#data
The most recent climate
normal period is of
reasonable length and
consistency for analysis.
0
10
20
30
40
50
60
70
TotalTornadoReports
Decade
1981-90 1991-00 2000-10
12. New England Tornado Climatology
New England Tornado Climatology
(1981-2010)
http://www.spc.noaa.gov/wcm/#data
13. New England Tornado Climatology
New England
Tornado
Climatology
(1981-2010)
http://www.spc.noaa.gov/wcm/#data
Tornadoes occur
most often during
warm season
from May
through
September.0
5
10
15
20
25
TotalTornadoReports
CT MA ME NH RI VT
14. New England Tornado Climatology
New England
Tornado
Climatology
(1981-2010)
http://www.spc.noaa.gov/wcm/#data
Tornadoes occur
most often during
the afternoon
hours and rarely
occur over night.
0
5
10
15
20
25
TotalTornadoReports
CT MA ME NH RI VT
15. New England Tornado Climatology
New England
Tornado
Climatology
(1981-2010)
http://www.spc.noaa.gov/wcm/#data
Locations of New
England tornado
origins.
Highest highest
tornado density
occurs over
southeastern CT.
Tornadoes per 100 km2
1-2
1
<1
16. New England Population Distribution
Distribution of
New England
Urban Centers
http://2010.census.gov/2010census/data/
Southern New
England is part of
the densely
populated
northeast
corridor.
Image Source: Annemarie
Schneider/NASA Landsat
Distribution of Urban Surfaces (2010)
Providence
Boston
Worchester
Connecticut
River
Valley
17. New England Population Distribution
Distribution of
New England
Urban Centers
http://www.spc.noaa.gov/wcm/#data
Parts of southern
New England’s most
densely populated
urban/suburban
landscapes
are located within
the areas of highest
tornado
occurrence.
Total hazard is a
function of event
occurrence and
potential impact
Population Density
& Tornado Tracks
Population Density
18. -2
-1.5
-1
-0.5
0
0.5
1
1.5
2
-2 -1.5 -1 -0.5 0 0.5 1 1.5 2
TornadoOccurrence
Tornado Impact
New England Tornado Hazard
Total Tornado
Hazard for New
England Counties
(High/Low
Continuum)
http://www.spc.noaa.gov/wcm/#data
Tornado occurrence
calculated as an index
accounting for tornado
count and intensity (SPC).
Impact assessed as the
people/property that could
be impacted by a tornado
(US Census Bureau 2010).
Median
Median
http://2010.census.gov/2010census/data/
High
Occurrence/Low
Impact
High
Occurrence/High
Impact
Low
Occurrence/Low
Impact
Low
Occurrence/High
Impact
19. -2
-1.5
-1
-0.5
0
0.5
1
1.5
2
-2 -1.5 -1 -0.5 0 0.5 1 1.5 2
TornadoOccurrence
Tornado Impact
Total hazard is a
function of event
occurrence and
potential impact
New England Tornado Hazard
Total Tornado
Hazard for New
England Counties
(High/Low
Continuum)
http://www.spc.noaa.gov/wcm/#data
Median
Median
20 Counties (30%) 13 Counties (19%)
13 Counties (19%) 21 Counties (30%)
Providence
New Haven
Fairfield
Norfolk
Windham
http://2010.census.gov/2010census/data/
20. New England Tornado Hazard
Total Tornado Hazard for
New England Counties
(High/Low Continuum)
Densely populated counties of
southern New England coincide
with the region’s highest
tornado occurrence.
These areas have the
highest hazard relative to
the rest of the region.
http://www.spc.noaa.gov/wcm/#data http://2010.census.gov/2010census/data/
21. *
*
* *
**
New England Tornado Hazard
Total Tornado Hazard for
New England Counties
(Product of Occurrence
and Impact)
http://www.spc.noaa.gov/wcm/#data
Tornado probability of
occurrence
multiplied by the
probability of impact
humans/infrastructure.
Evaluated as a product may
overstate the relative hazard.
*
*
*
*
*
*
*
*
*
*
*
*
22. Next Step:
Beyond knowing where tornadoes are most likely to occur and the areas
where the impact will be highest, it is important to understand the
mechanisms that lead to the formation of tornadoes. Studies indicate
areas of enhanced convection and increased storm frequency during the
warm season that coincide with areas of highest tornado occurrence
(Lombardo & Colle 2010, 2011; Waslua et. al 2002; Murray & Colle 2011).
Prepare database of detailed weather observations (where available)
for the time of each tornado.
Compare the weather characteristics during each event to the general
atmosphere conditions associated with regional convective and other
severe thunderstorm events.
23. Resources:
Storm Prediction Center (SPC) Storm
http://www.spc.noaa.gov/wcm/#data
US Census Bureau (2010) http://2010.census.gov/2010census/data/
Dixon, R.W., A.E. Mercer, J. Choi, and J.S. Allen (2011) Tornado Risk
Analysis: Is Dixie Alley and Extension of Tornado Alley? Bulletin of the
American Meteorological Society 92(4), 433-441
Dixon, R.W. and T.W Moore (2012) Tornado Vulnerability in Texas.
Weather, Climate, and Society. 59-67. doi: 10.1175/WCAS-D-11-
00004.1
Lewis, T.R. (2006) The Tornado Hazard In Southern New England:
History, Characteristics, Student and Teacher Perceptions. Journal
of Geography 105, 258-266.
24. Questions?
New Hampshire State Climate Office
The New Hampshire State Climate Office (NHSCO) resides within the Department
of Geography at the University of New Hampshire.
The NHSCO is officially recognized by the American Association of State
Climatologists and the National Oceanic and Atmospheric Administration (NOAA).
http://www.unh.edu/stateclimatologist/ Follow on Twitter at: https://twitter.com/nh_sco
Notas do Editor
Average over time alone may be misleading given the vast differences in the area over which events are countedThe term tornado alley is used to describe the area of high tornado activity within the central plains Considering Tornado Alley, variations in calculations and variables considered can shift this zone between the Rockies and Apps. (Dixon)Location far away from this area are precieved “low risk” including New England where there is a sense that tornadoes “don’t happen here” (Lewis)
Knocked down thousands of trees, destroyed 200 buildings, injured two and killed one (only one in NH since 1950)
Reasons for the lack of tornadoes indlues topography (break up storms), urban areas, climate and coastal influence. (Lewis)
This tornado cut a 35 mi path through central MA during the afternoon of June 9, 1953 injuring 1228 and killing 90.This area now has a population density of ~530 people/mi2
THE TORNADO RAPIDLY INTENSIFIED AS IT MOVED INTO WESTSPRINGFIELD. THE TORNADO CAUSED EXTENSIVE DAMAGE TO INDUSTRIALBUILDINGS AND HOMES. THE TORNADO THEN CROSSED THE CONNECTICUT RIVER AT THE MEMORIALAVENUE BRIDGE AND INTO THE CITY OF SPRINGFIELD. HERE THE TORNADOPRODUCED EXTENSIVE DAMAGE TO THE SOUTH SIDE OF THE DOWNTOWN AREAWITH MANY HOMES DESTROYED. IN ADDITION COMMERCIAL BRICK BUILDINGSSUSTAINED MAJOR DAMAGE. IN MONSON WIDESPREAD DAMAGE OCCURRED TO COMMERCIALAND RESIDENTIAL BUILDINGS...WITH MANY HOMES COMPLETELY DESTROYED.THE ROOF OF MONSON HIGH SCHOOL WAS DESTROYED. FORESTED PARTS OFTOWN EXPERIENCED NEARLY COMPLETE DEFORESTATION. SOUTHBRIDGE AIRPORT.HERE NUMEROUS AIRCRAFT WERE LIFTED OFF THE GROUND AND INTO THEWOODS EAST OF THE AIRPORT.
Other evidence indicates additional smaller “alleys” in which tornado activity is high, such as Dixie Alley. Area weight annual averages are useful in identifying such areas but the large scale over which these statistics are calculated leads to still a more subjective or informal alley identification (Dixon)Identifying smaller regions of elevated tornado risk requires detailed a spatial assessment. For example, only two New England states cover an area >10,000 mi2 (MA ~10,000 and ME ~35,000).The 2011 official population estimate 6,526,548,[4] making it the largest metropolitan area in the South.Themetroplex is 8,991 sq mi (23,290 km2) making it larger in area than the U.S. states of Rhode Island and Connecticut combined.
There are issues in accepting past tornado reports, and tornado characteristics, as accurate. F-scale is still used for consistency with past data (Dixon).Recent advances in radar technology allows for greater detection of tornadoes, particularly low magnitudes events that were not observed by sight. The occurrence of F0 tornadoes has increased sharply since the 1990’s. Also, historic events reported as tornadoes may have been caused by other similar wind events that generate damage patterns that were difficult to distinguish from tornado damages.
The biggest concern using the entire dataset are the missing decades within the RI record.Many tornadoes are listed as “unknown” intensity prior to 1980Another issue is the anomalous increase in tornados from 1961 to 1970. This is due in part to an increase in the reported tornadoes in NH.
There were 34 tornadoes reported in NH from 1961-70. This is in sharp contrast to <20 reported in any other decade and the <10 reports per decade for the most recent 30 year (or climate normal period)The period from 1961-1972 totaled 42 reports with a well above average number of reports during the years 1961 1966 1968 1970 (4), 1972 (8), record of 1963 (9). All other years have no more than 3 reports in one year.
Typically range in intensity from F0-F3 with lower intensity tornadoes more common the further northPath lengths subject to outliers like the NH Northwood (1.6mi without) and Barrington tornadoes.The 3 lives lost in MA were from the F3 Barrington MA tornado on May 29 1995. Eventually becoming an F3 tornado, it formed within a supercell thunderstorm just east of the Hudson River and traveled from NY, where it crossed the Taconic Range, into MA where cut an 11mi path 500-1000m wide. (Bosart)In the SPC record this tornado is counted as an F4 though recent publications list it as an F3 at its greatest intensity.The one in NH was from the Northwood
Reports of tornadoes occurring as early as April exist in 1951-2010 recordThe latest event was in ME on 11/24/2005 with two small tornadoes in neighboring Cummberland and Sagadoc in MEAnother november event was three small tornadoes in Penobsquot and Sommerset CO in interior me on 11/7/71
The earliest one was a small, short-live F0 in Carroll Co NH occurring shortly after midnight on 9/29/2006The latest occurred shortly before midnight in Oxford Co ME on 8/13/1999 and on 6/5/2002 in Litchfield Co CTBoth were low intensity and short-lived
Highly urbanized counties of Fairfield, Litchfield, New Haven and Hartford have and average of 1-2 tornadoes/100km2 over the period of recordThe total threat of a tornado forming may be determined using climate data … but the potential impact a tornado could have on humans must also be considered when evaluating the total tornado “hazard”
Southern New England is part of the densely populated northeast corridor with a nearly continuous urban/suburban landscape stretching from New York City to Boston. Some of the most densely populated urban areas include the Providence-Boston and Worchester-Boston corridors as well as the New York suburbs of eastern CT and the CT river valley. Many of these areas coincide with the areas of highest tornado occurrence.
Many of these areas coincide with the areas of highest tornado occurrence.
High/low continuum
High/low continuum
NYC suburbs Fairfield new haven in CTWindham CT through Providence RI into Norfolk MA
Highest Tornado scores: Litchfield (25), Berkshire & Worchester (20), Arrostock (18), Oxford (17), New Haven & York (15), Fairfield (12), Cheshire & Providence (11)Highest Population: Suffolk (outlier), Bristol, Middlesex, Norfolk, Providence, Essex, Fairfield, New Haven, Harford, Bristol & KentFairfield hartfordlitchfieldmiddlesex new haven tolland and windham in CTHampshire middlesexnorfolkplymouthworcester MAAndroscogin york MEBelknap hillsboroughrockinghamstrafford NHbristol providence RIChittenden VT