2010 Tropical Cyclone Season Summary

Tropical Storm Colin | Hurricane Danielle | Hurricane Earl | Hurricane Igor

Three tropical cyclones entered the Canadian Hurricane Centre (CHC) Response Zone (RZ) in 2010. The CHC issued bulletins on four storms – one of which dissipated before entering the RZ (Tropical Storm Colin).  The CHC forecast desk was activated again when Hurricane Danielle entered the zone, affecting the southernmost portion of the Grand Banks off Newfoundland on August 30^th. Then, on September 4^th, the long-lived Hurricane Earl tracked over Nova Scotia, and forecasters posted hurricane watches and tropical storm warnings for a large portion of the Maritime Provinces. About two weeks later Hurricane Igor struck Newfoundland on September 21^st with severe impacts. Hurricane watches and tropical storm warnings were issued for the island portion of the province. The CHC issued a total of 79 information statements during the 2010 hurricane season.

Although the CHC did not issue any official bulletins after Hurricane Igor, Tropical Storms Nicole and Tomas contributed moisture to long, stationary frontal systems over the eastern U.S. and Canada in late September and early November. Remnants of Nicole brought major flooding and caused two fatalities in the southern Quebec while Tomas’ remnants over parts of New Brunswick and Nova Scotia caused serious flooding that washed away roads and bridges. 2011 was probably the most damaging and costly hurricane season for Canada in over 50 years (total damage costs have yet to be finalized).

Tropical Storm Colin

Storm Summary

In early August it appeared that Tropical Storm Colin would affect Canadian waters, and the CHC issued 11 bulletins and track forecasts in anticipation of Colin crossing the offshore marine forecast district. However, on August 8th Colin was a weakening tropical storm as it approached Bermuda from the south. The storm dissipated, becoming a tropical depression near Bermuda and did not enter the CHC RZ. 

Hurricane Danielle

Storm Summary

At one point a Category 4 hurricane, Hurricane Danielle was originally expected to travel south of the Response Zone, however an upper-level trough of low pressure kept Danielle on a more northerly heading. This trough also meant that extratropical transition began earlier than expected on Friday the 27^th. On August 30^th the center of the storm tracked just south of the Southern Grand Banks marine forecast district off Newfoundland as a Category 1 storm. Although the maximum winds associated with Danielle were decreasing as it passed the Grand Banks, its central pressure underwent a final period of deepening as it moved away from the Banks.   

Conditions

The only storm conditions over Canadian territory were gale-force winds measured at buoy 44140 located at 42.9N, 51.5W. Significant wave heights near 7 metres were measured by the buoy, much of which was from previously-generated swell earlier in Danielle’s life while travelling northeastward. Ocean swell also reached southern Newfoundland, but no adverse effects were reported. There was a trough extending north of the hurricane as it passed by the buoy, with winds originally veering (changing in a clockwise fashion) as the hurricane drew near, then backing (counterclockwise) quickly as it passed by to the south. 

Impacts

There were no obvious impacts over land.

Warnings & Information Statements

Gale warnings were issued for the southern halves of the Southeast and Southwest Grand Banks marine forecast district at 2230Z on August 29^th (8:00 p.m. local time).  Given that buoy 44140 straddles the boundary between these forecast regions, and that the wind readings were near gale-force, the gale warnings are considered to have materialized. Wave height forecasts were very accurate, with 5 to 7 metres officially predicted on Monday morning, August 30^th. Significant wave heights near 7 metres were reported from 6:30 a.m. to 9:30 a.m. Newfoundland Time on August 30^th at buoy 44140. A total of 12 information statements were issued on Danielle, including a pre-emptive one on Friday, August 27^th when it appeared that the CHC desk would not need to be activated.

Coordination and Communications Efforts

The CHC initially contacted the regional weather office in Gander (Newfoundland and Labrador Weather Office – NLWO) on Friday, August 27^th to discuss a pre-emptive bulletin regarding Danielle and the monitoring of the storm’s track that weekend. With the trough affecting Danielle’s course, the CHC desk was activated late on Saturday the 28^th. On Sunday the 29^th the CHC communicated with the NLWO and the Canadian Meteorological Center to discuss the numerical weather model predictions. The CHC and the National Hurricane Center (NHC) in Miami had a final coordination call on Monday morning, August 30^th. There were a few media inquiries over the course of Danielle’s life, primarily relating to the possible impact of the storm in eastern Canada and why the season had been so quiet until then.

Hurricane Earl

Storm Summary

Earl formed in a traditional manner off the Cape Verde Islands on August 27^th and moved westward for several days, reaching hurricane strength just east of the Leeward Islands of the Caribbean. Earl moved west-northwest brushing the northeastern Caribbean Islands while attaining Category 4 intensity. From September 1^st to the 3^rd, the hurricane brushed past Cape Hatteras, North Carolina then moved toward Cape Cod, Massachusetts while rounding the western flank of the Subtropical High. As Earl moved northeast late on September 3^rd its intensity dropped to Category 1 status, however, the wind field expanded significantly. On September 4^th at 10:30 a.m. ADT, Earl made landfall as a 120-km/h Category 1 hurricane about 35 km southwest of Liverpool, Nova Scotia, with a central pressure remaining in the low 960-millibar range. Earl’s forward speed of motion was 75 km/hour while crossing central Nova Scotia and into the Gulf of St. Lawrence and the storm was a 100-km/h tropical storm as it moved across eastern Prince Edward Island between 3 and 4 p.m. Post-tropical storm Earl’s forward speed slowed significantly and rapidly weakened in intensity as the storm approached southeastern Labrador.

Conditions

Earl brought high winds to much of southern and eastern Nova Scotia with hurricane-force gusts and sustained overland wind speeds of mid tropical-storm force. Several stations in and around Halifax (urban area) registered peak winds near 110 km/h. Although rainfall was not significantly heavy with this storm, when the rain was accompanied by high wind gusts, conditions were certainly typical of a hurricane. Fortunately, the storm moved faster than initially expected, helping to reduce the rainfall amounts for many areas. The bulk of the rain fell left of the storm track over central and northwestern New Brunswick where up to 75 mm (3 inches) was measured, enhanced slightly by the presence of a weak front that was approaching the province. Ocean conditions along the Atlantic coast of Nova Scotia were turbulent and consistent with a Category 1 hurricane or strong tropical storm. Significant wave heights of 10 to 13 m (33 to 43 ft) were recorded with peak waves up to 23 m (75 ft) at the Halifax Harbour buoy (located outside the mouth of the harbour). Storm surge in Bedford Basin (head of Halifax Harbour) reached 120 cm or 4 ft. Some of the highest rainfall amounts and strongest wind data are shown below:

* Private or volunteer observation

** Sustained wind is a 10-minute mean at the 5m level above water surface

Impacts

The primary impact from Earl was wind damage to trees and related problems. Numerous trees were uprooted or trunks snapped over central and eastern Nova Scotia and in parts of western Newfoundland. Many large tree limbs fell onto Halifax area streets resulting in large-scale power failures, leaving up to 200 000 Nova Scotia Power customers without electricity at some point during the storm. It was a few days before power was restored for the hardest-hit areas such as eastern Halifax County and Guysborough County in Nova Scotia. Corner Brook in Newfoundland suffered major tree damage as what was then Tropical Storm Earl passed to the west over the Gulf of St. Lawrence. Trees and large branches were also reported downed in New Glasgow and Antigonish, Nova Scotia. Winds caused minor damage to roofing and cladding materials and light to moderate damage to signage.   

Fortunately there was no significant surge or wave-related damage due to the low tide at the time of the hurricane’s arrival. The high winds did, however blow sea spray inland causing salt burn of deciduous/hardwood foliage and vegetation which consequently shriveled and turned brown. High winds also shredded and thinned-out foliage of exposed trees well inland. Little in the way of rainfall impacts were reported in Nova Scotia and Newfoundland & Labrador however there was some minor street flooding in Prince Edward Island and New Brunswick.

Warnings & Information Statements

The CHC issued a preliminary statement on Earl the morning of Monday, August 30^th and the first regular bulletin was issued at 3 p.m. Atlantic Daylight Time (ADT) on Tuesday. Bulletins were issued every six hours thereafter, with intermediate bulletins issued every three hours starting at midnight on Thursday night. 

Tropical Storm watches were first posted for southwestern Nova Scotia early on Thursday September 2^nd. The first hurricane watches were issued for southwestern Nova Scotia later that day around 3 p.m. Tropical Storm warnings were issued early Friday morning for much of Nova Scotia and Prince Edward Island, followed by parts of southern New Brunswick that afternoon. A Hurricane Watch was extended eastward at 9 a.m. on Friday to include Lunenburg and Halifax Counties of Nova Scotia.  Tropical Storm warnings were issued Saturday afternoon at 4 p.m. NDT for western Newfoundland once it became apparent that Earl was retaining tropical characteristics farther north than earlier anticipated. This was a result of the storm’s rapid forward motion on Saturday.

Lead times for the tropical storm warnings for the Maritime Provinces averaged about 24 hours ahead of the storm’s arrival. The tropical storm warnings for western Newfoundland were issued 8 to 12 hours before the storm. 

Four of the eight official public forecast regions under the hurricane watch experienced hurricane-force gusts and sustained wind speeds that were not far below hurricane-force (the immediate coastline of Halifax and Guysborough Counties for instance). The CHC issued 34 information statements and regional weather offices (the Atlantic Storm Prediction Centre (ASPC) and the NLWO) issued 34 marine wind warnings during the event. 

Coordination and Communications Efforts

Earl was a long-lived storm and media interest began very early – a full five days prior to its impact in this region. The NHC track maps (which extend out to five days) marked the beginning of this heightened level of interest starting on Monday, August 30^th. Over the days that followed there were numerous coordination efforts conducted with the ASPC, NLWO, the Canadian Meteorological Aviation Centre, the media, and other government departments including emergency management offices.

A daily media technical briefing was held from Wednesday, September 1^st to Friday September 3rd from 1 to 2 p.m ADT. A fourth teleconference-only briefing was held on the morning of Saturday September 4^th (the day of the event) to communicate the latest storm conditions and impacts. About 100 questions were answered during the four technical briefings with about 220 additional individual media requests met in the period leading up to and throughout the event. A Warning Preparedness Meteorologist (WPM) from the Meteorological Service of Canada (MSC) was situated at the Emergency Operations Centre during the hurricane to aid in coordination and messaging.  Teleconference calls were held with other forecast offices (such as the aviation forecasting office in Montreal) and for the WPMs after each CHC forecast issuance.  Coordination between the CHC and the NHC occurred as watches and warnings were put in place on Thursday. Key coordination calls occurred late Friday and throughout Saturday, Sept 4^th as the storm accelerated.

There was a period of approximately 10 hours prior to the landfall when the NHC was classifying Earl as a tropical storm, while the CHC was referring to it as a hurricane (9 km/h difference between the two categories), an unintended discrepancy that generated some public confusion. Since the overall motion of the storm was accelerating, this small increase in wind at landfall is reconcilable, although 9 km/h of maximum sustained wind speed estimate is certainly within observational uncertainty. Discussions after the season resulted in Earl being officially classified as a hurricane at landfall, but a strong tropical storm in the hours leading up to landfall. 

Hurricane Igor

Storm Summary

Igor formed near the Cape Verde Islands off Africa on September 8th, 2010 and moved on a general westward course across the tropical Atlantic in a typical fashion. The storm did not attain hurricane strength until early on September 12^th. The most intense state of the storm occurred early on September 15^th when its minimum central pressure fell to 925 mb and maximum winds reached 250 km/h – just below Category 5 intensity. Then, while on a northwestward heading, the hurricane weakened to Category 1 but expanded greatly and maintained a very low central pressure in the 940-mb range. Igor tracked just west of Bermuda early on September 20^th delivering Category 1 wind conditions there. Beyond Bermuda, Igor tracked northward then north-northeastward and began to accelerate. The same day a sharp frontal system over Newfoundland became stationary, drawing the moisture and extremely heavy rainfall streaming northward from the hurricane. Then early on September 21^st Igor responded to an upper-level trough of low pressure associated with the front and consequently re-intensified throughout the day while tracking toward (then passing along the eastern coastline of ) Newfoundland's Avalon Peninsula. The central pressure fell to near 950 mb and winds increased by about 20 km/h to reach almost 140 km/h as it struck eastern Newfoundland. The trough interaction caused the storm to track in a more northerly direction and eventually merge with another large area of low pressure on September 23^rd. 

A detailed operational storm summary (AWCN16 CWHX) was prepared within two days of the event, providing a meteorological assessment and historical perspective for the media and ensuring that consistent data was conveyed internally and with partnering agencies. This summary in its original form appears online HERE.

Conditions

Hurricane Igor and the associated front and trough were the story behind the intensity of this combined, extratropical transition event. The greatest impact with Igor was the rain, with well over 200 mm (8 inches) falling over the Burin and Bonavista Peninsulas. A large area of 100+ mm rainfall (4+ inches) occurred over the eastern half of Newfoundland island. Winds were also particularly strong on the western side of the sharp front and western side of the center of Igor as it tracked just east of the Avalon Peninsula. Sustained hurricane-force winds (~120 to 130 km/h) were recorded with gusts in the 150 to 170 km/h range. Over the marine forecast district, 13-metre (~43-ft.) maximum wave heights were reported east of the storm track, with 12-metre (~39-ft.) maximum significant wave heights reported at the Hibernia oil platform, about 250 km east of the track. Peak wave heights of 25 metres (~80 ft.) occurred to the east of the track. Also at Hibernia, maximum sustained winds of 174 km/h were reported by the 140-m level (456-ft.) anemometer.  Storm surge of 70 to 100 cm (~2 to 3 ft.) was measured by tide gauges around the eastern portion of Newfoundland.

* Private or volunteer observation
** 10-minute sustained
*** Rain gauge failed/overflowed around the 200-mm mark, radar-based estimate thereafter

* Data record from this buoy indicated a maximum of 28 m (92 ft.) which requires further analysis to verify.

Impacts

Excessive rainfall runoff and swollen rivers caused extensive damage to roads, bridges and some buildings over a large portion of eastern Newfoundland. The impacts were most serious on the Bonavista and Burin Peninsulas where many communities were cut off from the principal road network due to road washouts. These washouts were severe, requiring complete bridge replacements and rebuilding of roadbeds. One person was killed when the road he was driving on washed away. Torrents of water from overflowing rivers destroyed some buildings and changed the course of some rivers. Large portions of river banks and roads were removed by the extreme river flows which set new records. In some cases, full-grown trees were felled by the surging water flow. The Canadian military was brought to Newfoundland and federal financial aide was allocated to help with the recovery efforts. Temporary bridges had to be erected to reconnect communities with essential services such as fuel and food, taking a couple of weeks in some cases. The most critical priority for road reconstruction was to repair a washed away portion of the Trans-Canada Highway in Terra Nova National Park which had created a giant ravine about 30 metres (~100 ft.) wide, completely disconnecting the majority of Newfoundland’s population from the rest of the island.   

In addition to the flooding, very high wind speeds were witnessed over the eastern peninsulas of Newfoundland, toppling many trees (especially in urban areas), and causing structural damage which included complete roof loss and curtain wall collapse.

Warnings & Information Statements

The CHC first issued a preliminary statement on Igor on the afternoon of Friday, September 17^th, four days prior to the main event (on Tuesday September 21^st). This early bulletin was intended to officially signal the beginning of the Hurricane Centre monitoring the storm and to notify the public about the approaching storm prior to the weekend. 

The CHC began issuing regular bulletins in the afternoon of Saturday, September 18^th. Track forecasts from Saturday through till Monday evening, September 20^thindicated that Igor would pass through the central portion of the Grand Banks. However, during the early part of Tuesday, September 21^st, it became apparent that Igor was going to track farther to the northwest and closer to Newfoundland.  Even during the day of the event, the position and track forecast had to be continually adjusted closer to land as the details of the upper-level trough influence were evolving. Intensity forecasts were highly consistent during the days leading up to the event for Igor’s passage past Newfoundland, indicating a transitioning hurricane with 120 to 140-km/h winds. Early on Monday September 20^th, forecasts began to point to a possible re-intensification during the extratropical transition process over the Grand Banks.

Although the rainfall threat of this event was anticipated two to three days in advance, the wind threat was not specifically expected to be an issue over land until the day before Igor’s arrival (Monday September 20^th). Computer models on Monday began to show a greater likelihood of a very strong wind jet on the cold side of the interacting front located north of Igor. As a result, tropical storm warnings and wind warnings were posted Monday afternoon for eastern Newfoundland (which falls within the target lead time of about 24 hours). Hurricane watches were issued early on Tuesday, September 21^st as it became even more apparent that the vigorous trough/hurricane interaction would bring high winds across the eastern peninsulas. Most (90%) of the watches and warnings issued for Igor verified as “hits”.

The CHC issued 22 information statements on Hurricane Igor.

Coordination and Communications Efforts

Media interest in this storm was much less than what was experienced with Hurricane Earl in the Maritime Provinces two-and-a-half weeks earlier. This lower level of media (and public) interest was likely due to a number of factors, including the different storm track scenarios. With Hurricane Earl, it was known that there was a greater likelihood of impact somewhere in Atlantic Canada at a much earlier point than for Igor which was much further out in the Atlantic Ocean. 

Even with the CHC’s issuance of a preliminary statement as a “heads-up” on Friday the 17^th about Igor, there was surprisingly little media interest over that weekend.  It was much less than for Hurricane Earl which was a prominent news story four days before the storm. Interest began to ramp-up once the CHC and the NLWO began to alert the public (the day before) about very high winds, and once the extreme impacts became known. One teleconference-style technical briefing was held on the morning of Tuesday, September 21^st (the day of the storm’s arrival) for media and Emergency Management representatives. The CHC dealt with about 35 additional media requests, some of which went directly to the NLWO and were later handled by the CHC. 

Interoffice communication between the CHC and the NLWO began early on Friday, September 17^th, prior to the activation of the CHC desk. This early communication was important in establishing how to best describe the event in the long-range weather forecasts. Communication between the CHC, the NLWO and the Canadian Meteorological Aviation Centre continued throughout the weekend (September 18^th and 19^th). At 11 a.m. ADT on Monday, September 20^th, the CHC held a conference call briefing for the Canadian Government Operations Centre (GOC). Another briefing was held on Tuesday morning at 11 a.m. ADT.   

Environment Canada’s Warning Preparedness Meteorologists (WPMs) worked closely with Fire and Emergency Services of Newfoundland and Labrador - the provincial agency primarily responsible for alerting municipalities and other sectors of possible threats in the period leading up to, during and after the event.  

The CHC and the National Hurricane Centre in Florida coordinated on the issuance of watches and warnings and on the designation of Igor’s post-tropical status on September 21st. 

Date modified:

2013-07-23