Canadian Hurricane Centre
Meteorological Service of Canada
45 Alderney Drive
Dartmouth, Nova Scotia B2Y 2N6 CANADA
Website: http://www.hurricanes.ca
2011 TROPICAL CYCLONE SEASON SUMMARY
Eight tropical cyclones entered the Canadian Hurricane Centre (CHC) Response Zone
(RZ) in 2011 but four of those were on the very edge of the zone. The CHC issued
bulletins on eight storms in total. The four main events were Hurricane Irene entering
Quebec from northern New Hampshire on August 29th as a post-tropical storm, Hurricane
Katia tracking well offshore south of Newfoundland on September 10th, Hurricane Maria
which made landfall as a strong tropical storm in Newfoundland on September 16th, and
Hurricane Ophelia entering the RZ as a category-3 storm and land falling in Newfoundland
as a strong post-tropical storm on October 3rd.
Of these four storms Irene had the greatest impact on Canadian forecast territory in 2011.
Gusty winds and heavy rainfall created problems in Quebec. Rivers flooded and damage
to roads and bridges was experienced. Winds broke tree branches and caused some
interruptions to electrical service. Katia was primarily a wave event creating spectacular
ocean swells along the Atlantic Coast of Nova Scotia. Maria and Ophelia took direct aim
on Newfoundland, but did not cause significant issues and were much less severe than
Hurricane Igor of the previous year.
BULLETIN
SUMMARIES
Hurricane
Information
Statements
(WOCN3X/4X CWHX)
Number of Storms
Represented by
these Bulletins
2011
2010
2009
2008
2007
2006
2005
2004
2003
99
79
37
90
48
93
87
104
113
8
4
2
6
4
5
7
8
8
Below is a summary of the 4 main tropical events affecting Canadian territory in 2011
comprising 85% of CHC’s forecast statements for the season. The remaining 15% were
for weaker storms, including nine statements issued for Tropical Storm Gert in mid
September. Gert dissipated without affecting the Canadian marine forecast district.
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Hurricane Irene
Storm
Hurricane Irene made two U.S. landfalls – the first in North Carolina and the second over
western Long Island near New York City. Irene was a very large and damaging storm
affecting a large population of the eastern U.S. The storm weakened to tropical storm
strength quickly after landfall and underwent transition to post-tropical over northern New
Hampshire on August 29th. The centre of the low then tracked along the Quebec/Maine
border, north of the Gaspe region of Quebec and into Labrador. As Irene underwent
transition to extratropical, a sharp warm front formed over the St Lawrence River valley,
enhancing wind and precipitation in that region.
Conditions
The heaviest rainfall from Irene in Canada was experienced in southern Quebec (see
table below) where 150 mm fell in the hilly Charlevoix region on the north side of the St.
Lawrence River. Montreal received near 65 mm of rain, most of which fell over a 5-hour
period on August 28th. Up to 90 mm of rain fell east of the storm track over northern New
Brunswick. Generally less than 25 mm fell over Nova Scotia. The strongest winds blew
from the northeast along the St. Lawrence River southwestward to Montreal where gusts
were near 80 km/h. These winds were associated with the warm front north of Irene and
exceeded 100 km/h at a few exposed island locations (see table below). East of the storm
track winds gusted to near 90 km/h over the Maritime Provinces. These winds generated
choppy conditions in local harbours around the region.
Station
Ile D’Orleans, QC
Ile Aux Grues, QC
Pointe De L’Islet, QC
Summerside, PEI
Moncton, NB
Yarmouth, NS
Monctreal, QC
Fredericton, NB
WindGusts
(km/h)
113 (92 sust.)
104 (78 sust.)
98
96
93
93
78
78
Station
Charlevoix, QC
Thetford Mines, QC
Sherbrooke, QC
Doaktown, NB
Montreal, QC
Rainfall
(mm)
150
109
107
89
66
Impacts
Flooding occurred over parts of southern Quebec resulting in some road washouts and
causing one direct fatality when a vehicle was swept into a river northeast of Montreal after
a large culvert collapsed beneath the road. Winds brought down several trees in Quebec
and New Brunswick leaving tens of thousands of people without electricity. Rough seas
and some large waves caused minor problems along the coast. In southern New
Brunswick, waves were spreading rocks and other debris across a road near a popular
beach.
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(Left): Irene flooding caused damage on Route 138 Saint-Simeon, QC (Marika Wheeler/CBC)
(Right): Tree-related damage in Charlotteown, PEI (The Guardian)
Warnings & Information Statements
There were 26 unique information statements (WOCN31 CWHX) issued by the CHC for
this event. Tropical storm warnings were posted over the southwestern Maritime
Provinces. Regular wind and rainfall warnings were issued in Quebec since the storm had
become post tropical as it was affecting that region. The transition was most apparent
with the warm front development combined with topographic effects on the wind in the St.
Lawrence Valley region. Gale to storm-force wind warnings were issued for most Atlantic
Canada waters and the St. Lawrence River region.
Coordination and Communications Effort
The CHC conducted daily conference calls at 3:30 pm ADT for operational weather offices
in Eastern Canada. These included the Quebec Storm Prediction Centre, Canadian
Meteorological Aviation Centre, Atlantic Storm Prediction Centre, and other groups
including Warning Preparedness Meteorologists in Quebec and Atlantic Canada.
Planning meetings were held daily around 9:30 am ADT with Environment Canada
Department Heads in Atlantic and Quebec regions to maintain coordination on various
activities. Daily briefings were given by the Warning Preparedness Meteorologists for
Sécurité Civile du Quebec and emergency managers in the Maritimes, both federally and
provincially.
Page 3
Hurricane Katia
Storm
Hurricane Katia formed off the Cape Verde Islands on August 30 th and travelled
northwestward for almost 9 days, intensifying to category-4 strength briefly on September
6th. With its persistent northwestward tracking, Katia generated large waves that crashed
ashore over the Atlantic coast of Nova Scotia and southern coast of Newfoundland. On
September 9th, Katia took a sharp turn toward the northeast and accelerated rapidly on
September 10th while passing south of Newfoundland and undergoing extratropical
transition.
Conditions
The lowest estimated pressure over Canadian waters was 955 mb which occurred during
the latter stage of extratropical transition. Although the cloud shield associated with Katia
shrouded much of the Atlantic Provinces, the precipitation stayed well offshore. Rainfall at
Sable Island (about 300 km north of Katia’s centre) was only 20 mm but totals between 60
and 120 mm would have been likely if the centre tracked over land.
Offshore waters south of the Atlantic Provinces were hardest hit with peak waves above
10 metres. The Atlantic coast of Nova Scotia experienced heavy surf on Friday,
September 9th (see photograph below) and these conditions spread to the south coast of
Newfoundland on the 10th. Details from Canadian offshore buoys:
Buoy
Laurentian Fan 44141
Tail-of-the-Bank 44140
SW Grand Banks 44138
East Scotia Slope 44137
Halifax Harbour 44258**
Max wind *
Sust./gust (kts)
46/59
63/M
36/47
36/46
19/23
Significant
Wave Height (m)
7.7
7.6
6.6
6.0
2.7
Maximum Wave
Height (m)
12.3
11.6
13.6
9.9
4.8
* Sustained wind is a 10-minute mean at the 5-m level above water surface. Gust is a 5-s peak over a 10
minute interval near the top of the reporting hour
** Due primarily to swell
Page 4
Katia-spawned waves at Lawrencetown, Nova Scotia – September 9th, 2011 (Chris Fogarty)
Impacts
The only known impact to land territory was minor wash-up of debris from large waves
travelling north of the hurricane. At least one incident was reported along the south shore
of Nova Scotia when someone was caught up in rip currents at a local beach.
Warnings & Information Statements
There were 22 unique information statements issued by the CHC for this event. No
warnings were issued for land territory except a special statement for abnormal coastal
water levels around the eastern portion of Newfoundland due to a known oceanographic
phenomenon (a “rapid tide” effect) that has caused flooding in the past. The predicted
oscillations in water levels did occur but fortunately were not present at high tide.
Storm and hurricane-force wind warnings were posted for offshore waters in Canadian
territory.
Coordination and Communications Effort
The Newfoundland and Labrador Weather Office in Gander and the Canadian Hurricane
Centre in Dartmouth maintained close communication while Katia was affecting offshore
waters. Special attention was given to the coastal water level statement to ensure clear
terminology and communication to the public. Warning Preparedness Meteorologists
coordinated with provincial and federal emergency management officials.
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Hurricane Maria
Storm
Maria formed on September 7th in the mid tropical Atlantic and tracked westward then
northwestward, skirting the Caribbean Islands from September 10th to 12th. Maria – while
still a tropical storm – moved northward to the west of Bermuda and attained hurricane
status on September 15th at 35oN latitude. Hurricane Maria accelerated toward the
northeast thereafter, making landfall in Newfoundland on the afternoon of September 16th
as a strong tropical storm in the Cape St. Mary’s/Argentia area of the Avalon Peninsula.
After transition to a post-tropical storm while exiting Newfoundland, Maria merged with a
large non-tropical low that had been intensifying over southeastern Labrador. The
combined low was actually a more potent storm for northern Newfoundland and Labrador
on September 17th.
GOES VIS image of Maria approaching Newfoundland
Conditions
The central pressure of Maria at landfall was estimated to be 985 mb. Strongest winds
with the storm were to the right of its track. The highest winds were far enough from the
centre at landfall such that they did not pass over land. The maximum wind jet was just
offshore to the east of the Avalon Peninsula. The remnant eye of Maria covered most of
Placentia Bay and up into the Clarenville area of the province just prior to nightfall. Winds
were observed diminishing to light as the “eye” passed with partially clearing skies,
followed by a modest increase in wind speed and returning cloud cover after the centre
moved away.
The storm was a very close call for the island region. Offshore winds blew at hurricane
force for at least two hours about 180 km east of the storm track. Satellite imagery
Page 6
indicated that the radius of maximum wind tracked about 50 km east of Cape Spear – the
island’s most easterly point of land. Storm surge was not a threat, owing to the fast
motion of Maria and the limited time for water to build up into the bays. Wind and rainfall
data can be found in the following table:
Station
Cape Pine, NL*
Cape Race, NL
Grates Cove, NL
Argentia, NL
St. John’s, NL
WindGusts
(km/h)
103
100 (67 sust.)
87
85
80
Station
St. Lawrence, NL
Burgeo, NL
Argentia, NL
Bonavista, NL
St. John’s, NL
Rainfall
(mm)
63
61
30
25
13
* Private or volunteer observation
Buoy
SW Grand Banks 44138
Nickerson Bank 44251
Laurentian Fan 44141
Banqureau Bank 44139
East Scotian Slope 44137
Tail-of-the-Bank 44140
Max wind *
Sust./gust (kts)
52/70
38/49
43/58
30/38
27/35
30/37
Significant
Wave Height (m)
6.4
5.9
5.9
5.4
5.3
3.4
Maximum Wave
Height (m)
10.5
12.2
9.8
8.8
8.6
6.6
* Sustained wind is a 10-minute mean at the 5-m level above water surface. Gust is a 5-s peak over a 10
minute interval near the top of the reporting hour
Impacts
Impacts from Maria were quite minor, since the highest winds remained offshore. There
were only a few reports of light objects being blown off private properties. For a land
falling storm near hurricane-strength, there were surprisingly no interruptions to the power
grid.
Warnings & Information Statements
There were 18 unique information statements issued by the CHC for this event. A
hurricane warning was issued for the southern part of the Avalon Peninsula of
Newfoundland while a tropical storm warning was posted for remaining parts of the
peninsula as well as the Burin and Bonavista Peninsulas. The strong winds did not
materialize over land, and the warnings were quickly ended once forecasters became
aware that the highest winds were remaining offshore.
Storm and hurricane-force wind warnings were issued for marine forecast regions near
and to the east of Maria’s track. Hurricane conditions did materialize over the
southwestern Grand Banks district.
Coordination and Communications Effort
Page 7
Close communication was maintained between the Newfoundland and Labrador Weather
Office in Gander and the Canadian Hurricane Centre in Dartmouth. Technical media
briefings via WebEx were given during the days prior to the storm’s arrival by the Head of
the CHC and the Warning Preparedness Meteorologist.
Warning Preparedness
Meteorologists took part in regular federal and provincial emergency management
briefings for the island of Newfoundland leading up to the event.
During the evening of September 15th, the National Hurricane Center changed the forecast
from a glancing-blow tropical storm to a direct-hit hurricane landfall in Newfoundland.
After a detailed discussion between the NHC and the CHC, a decision was made to issue
a tropical storm warning and hurricane watch for the Avalon Peninsula, with a lead time of
about 21 hours. The hurricane centers continued to coordinate on watches and warnings
for the remainder of the event.
Hurricane Ophelia
Storm
Ophelia formed in the mid tropical Atlantic on September 21 st and tracked northwestward
as a tropical storm over the following week. It was not until September 30 th when Ophelia
began to move on a more northerly course that it strengthened to hurricane strength. In
fact, Ophelia rapidly intensified from tropical storm strength to category-3 intensity in 24
hours. The storm intensified further to a 940-mb category-4 hurricane while tracking
northeast of Bermuda on October 2nd. The compact hurricane entered the CHC
Response Zone as a strong category-3 then rapidly weakened as it travelled over cooler
ocean water temperatures. The weakening occurred quickly enough so that Ophelia
dropped below hurricane strength as it made landfall on the Avalon Peninsula of
Newfoundland near the community of Placentia. The storm centre appeared to reform
approximately 50 km north of landfall, then track north of the capital city of St. John’s.
Conditions
The central pressure of Ophelia was estimated to be 988 mb at landfall. Maximum winds
at landfall were near 55 or 60 kts (100-110 km/h) about 50 km offshore. Wind gusts to
100 km/h were reported along the immediate southern coastlines of the Avalon and Burin
Peninsulas.
Inland gusts near 80 km/h were reported. These wind speeds are not
unusual for Newfoundland. Winds noticeably diminished as the centre of the storm
passed through, then increased from the west, gusting to near 90 km/h after the storm
core moved away. The primary wind and rainfall figures are found in the table below.
Rainfall was light near the center of the storm and to its right, as is typical for extratropical
transition. Not far to the left of the track, heavy rainfall came quickly – amounting to near
50 mm in 3 hours.
In the offshore region, the axis of maximum winds extended from the Laurentian Fan
forecast district to the northern Grand Banks. The large waves generated by these winds
(see table below) propagated northward reaching the coast of the Avalon region with
heights of 5 to 10 metres. Like Maria, two-and-a-half weeks prior, storm surge was not a
Page 8
significant factor. The highest reading from a tide gauge was 50 cm at Argentia, which
occurred at low tide.
Station
Cape Race, NL
St. Pierre/Miquelon, FR
St. John’s, NL
Sagona Island, NL
WindGusts
(km/h)
98 (67 sust.)
98 (68 sust.)
78 (61 sust.)
96 (85 sust.)
Station
Bonavista, NL
St. Lawrence, NL
Terra Nova Park, NL
St. John’s, NL
Gander, NL
Rainfall
(mm)
62*
58*
47
27
27
* peak one-hour rainfall just over 20 mm and 3-hr totals near 50 mm
Buoy
Laurentian Fan 44141
Banqureau Bank 44139
Nickerson Bank 44251
East Scotian Slope 44137
SW Grand Banks 44138
Max wind *
Sust./gust (kts)
52/70
43/57
36/46
23/29
34/42
Significant
Wave Height (m)
13.8
11.9
8.6
7.3
6.7
Maximum Wave
Height (m)
21.8
22.2
15.1
12.1
15.0
* Sustained wind is a 10-minute mean at the 5-m level above water surface. Gust is 5-s peak over a 10
minute interval near the top of the reporting hour
Impacts
Impacts from Ophelia primarily came in the form of flooding due to rainfall. The region
most affected by heavy downpours was the Burin Peninsula which was also hit hard
during Hurricane Igor the previous year. A drainage ravine overflowed in the town of
Belleoram, sending a cascade of rocks, mud and water into some homes causing heavy
damage to a couple of buildings. A brief state of emergency was declared in the
community.
In the photograph below, a large culvert was unearthed by the heavy water flow from
Ophelia. The same location was the site of a major washout the previous from Hurricane
Igor.
Page 9
(Left): Large culvert unearthed on the Burin Peninsula – Cynthia Farrell/Southern Gazette
(Right): Cascade of rocks caused by flash flooding in Belleoram – RCMP “B” Division, NL
Curious spectators attracted by the large ocean swell along the southern coastlines were
encouraged to stay well away from the wave-breaking zones as dangerous surf and rip
tides were created. There was some beachfront debris and wash-up in prone areas of the
southern Avalon Peninsula such as along a beach and causeway in the community of
Saint Vincent’s.
Warnings & Information Statements
There were 18 unique information statements issued by the CHC for this event. The CHC
maintained a conservative forecast for this event, issuing nothing “stronger” than a tropical
storm watch for the Avalon Peninsula of Newfoundland. However, hurricane-force
warnings were issued for the offshore forecast district. Rainfall warnings were issued for
the hardest-hit areas including the Burin Peninsula.
Coordination and Communications Effort
Similar to Hurricane Maria, close coordination was maintained between the Newfoundland
and Labrador Weather Office and the Canadian Hurricane Centre. The CHC emphasized
the importance of not over-warning the winds for the event. Regular briefings took place
between federal and provincial emergency managers. The conservative approach
certainly paid off, as Ophelia’s winds fell short of the conventional wind warning criteria for
the island (gusts of 100 km/h or more).
Author:
Dr. Chris Fogarty, Program Supervisor, Canadian Hurricane Centre
Edited by:
John Parker, Manager, Prediction and Training Section.
Final version: February 6, 2012
Page 10