Ra IV hurricane committee
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- REVIEW OF THE PAST HURRICANE SEASON Reports of hurricanes, tropical storms, tropical disturbances and related flooding during 2015 Report from Canada
- Warnings Information Statements
- Claudette” Storm and Synoptic History
- Coordination and Communications Efforts
- Henri” Storm and Synoptic History
- Impacts Mariners needed to be aware of strong to gale-force winds and elevated sea states offshore. “Joaquin”
REVIEW OF THE PAST HURRICANE SEASON Reports of hurricanes, tropical storms, tropical disturbances and related flooding during 2015 Report from Canada (Submitted by Canada)
The 2015 tropical cyclone season in the Atlantic Basin was slightly below average in terms of the number of named storms and had a relatively low impact on Canadian territory. Below is a map showing the four storms of tropical origin that affected Canadian territory in 2015. 
“Ana” Track Map of Tropical Storm Ana 
Storm and Synoptic History Tropical Storm Ana formed as a subtropical storm from a non-tropical area of low pressure north of the Bahamas on May 8th. Ana became fully tropical in nature by early morning of May 9th. Late on May 9th, Ana accelerated toward the coast of South Carolina while gradually weakening as it moved over cooler water closer to the coast. After landfall, Ana weakened to a tropical depression during the afternoon of May 10th. On May 12th, Ana became a remnant low. This low accelerated northeastward and merged with a frontal system near southwestern Nova Scotia late on May 12th. Impacts on Canadian territory were minimal. Warnings & Information Statements Early in the forecast process, indications were that Ana would track toward Atlantic Canada as a tropical depression or post-tropical storm. Although, forecasters were confident that the impacts from Ana to Atlantic Canada would not be significant, there was some degree of uncertainty with respect to organization of the system as it approached Atlantic Canada. The challenge for CHC was to determine if whether or not Ana would remain as an entity resulting in heavy rainfall for Nova Scotia. Since Ana was forecast by NHC to track toward Atlantic Canada as a tropical depression or post-tropical storm, the CHC responded to Ana by issuing one unique information statement to inform stakeholders that impacts to Canadian territory would be minimal. “Claudette” 
Storm and Synoptic History Tropical Storm Claudette formed from a surface low off the Carolina coast. A tropical depression formed by 06:00 UTC on July 13th as thunderstorm activity increased near the centre of this low over the Gulf Stream. By 12:00 UTC that day, it had intensified into Tropical Storm Claudette. Claudette moved northeastward ahead of a trough of low pressure and reached its maximum intensity of 45 knots (85 km/h) on July 13th. On July 14th, Claudette began to weaken and by 00:00 UTC July 15th, the storm became a remnant-low. Later that day the remnant-low was absorbed by a front south of Newfoundland. Conditions Gale-force winds occurred over extreme eastern waters of the Maritime marine district. However, winds diminished below gale-force before Claudette reached Newfoundland and its marine district. Wave heights offshore were significant, likely in part due to wave resonance. Offshore buoys recorded the following wave heights: Buoy 44258 (Halifax Harbour) 1.5 metres (Peak Wave 2.4) Buoy 44137 (East Scotian Slope) 2.7 metres (Peak Wave 4.6) Buoy 44141 (Laurentian Fan) 5.2 metres (Peak Wave 7.2) Buoy 44139 (Banquereau Bank) 4.6 metres (Peak Wave 9.4) Buoy 44251 (Nickerson Bank) 1.9 metres (Peak Wave 3.4) Impacts The main impacts over land from Claudette were heavy showers and gusty winds over southeastern Newfoundland. In addition, rain and fog from Claudette’s remnants caused flight cancellations in southeastern Newfoundland. Offshore, impacts included gale-force winds and average wave heights of 5 metres, with peak waves up to 9 metres recorded. In July, gale-force winds and large seas are not very common in Atlantic Canada. Therefore, mariners had to be extra diligent about Claudette, especially over parts of the southern-most slope waters. Coordination and Communications Efforts There was close coordination between the CHC, and the Atlantic Storm Prediction Centre (ASPC) and the Newfoundland and Labrador Weather Office (NLWO). There was also initial coordination between the National Hurricane Center (NHC) and the CHC due to the sudden formation and intensification of Claudette. “Henri” 
Storm and Synoptic History Tropical Storm Henri formed southeast of Bermuda on September 9th. The storm tracked slowly northward at first then accelerated to the north on Sept 10th. Due to increasing westerly shear, Henri was only able to reach a maximum intensity of 45 knots (85 km/h) on Sept 10th. On September 11th an upper-level trough caused Henri’s circulation to degrade. By early morning on September 12th, Henri had lost its closed centre and later merged with a non-tropical low. Conditions Rain and gusty winds occurred over eastern sections of the Avalon Peninsula. Rainfall amounts were 25 millimetres or less. Gale-force winds were reported over the Grand Banks as the remnant low of Henri tracked through. Seas were reported by a ship east of Henri to be 3.5 metres. Wave heights from moored offshore buoys were generally in the two to 3 metre range with peak waves generally in the 4 to 5 metre range. Offshore buoys recorded the following wave heights: Buoy 44137 (East Scotian Slope) 2.1 metres (Peak Wave 3.8) Buoy 44141 (Laurentian Fan) 2.7 metres (Peak Wave 5.2) Buoy 44139 (Banquereau Bank) 2.7 metres (Peak Wave 4.2) Buoy 44251 (Nickerson Bank) 2.7 metres (Peak Wave 4.8) Impacts Mariners needed to be aware of strong to gale-force winds and elevated sea states offshore. “Joaquin” 
Storm and Synoptic History Hurricane Joaquin developed from a non-tropical low to become a tropical depression on September 28th. On September 29th, the cyclone underwent rapid intensification to become Hurricane Joaquin on September 30th and a Category 3 hurricane on October 1st. On October 3rd, Joaquin began accelerating away from the Bahamas. It reached its maximum intensity on October 4th. Hurricane Joaquin then began to weaken and curve to the north-northeast later on October 4th passing Bermuda as a Category 2. Joaquin then curved east-northeast around the periphery of a high to the east while gradually weakening. On October 7th Joaquin dropped below hurricane strength while located well southeast of the Grand Banks. Conditions Large swell waves reached the southern coastlines of Nova Scotia and Newfoundland. These waves were near 2 metres with peak waves near 4 metres as shown by the table of buoy data below. Gale-force winds very likely occurred over the extreme southern Scotian slope waters off of Nova Scotia and the extreme southern Grand Banks. Laurentian Fan Buoy reported a gust to 35 knots. However, the winds south of that buoy within the southernmost marine areas were almost certainly stronger and sustained at gale-force. Offshore buoys recorded the following wave heights: Buoy 44258 (Halifax Harbour) 2.1 metres (Peak Wave 3.7) Buoy 44137 (East Scotian Slope) 3.6 metres (Peak Wave 6.2) Buoy 44141 (Laurentian Fan) 4.1 metres (Peak Wave 6.6) Buoy 44139 (Banquereau Bank) 3.5 metres (Peak Wave 5.6) Buoy 44251 (Nickerson Bank) 2.1 metres (Peak Wave 4.4) Impacts The large swell waves reached the south-facing coastlines of Nova Scotia and Newfoundland as well as gale-force winds over the extreme southern marine areas. However, If Hurricane Joaquin had occurred during the summer, the impacts would have been much greater due to much higher sensitivity to coastal wave action. Rip currents almost certainly occurred. Large waves and rip currents would have been a hazard to swimmers. Warnings & Information Statements There were two information statements issued by the CHC on this storm on October 2nd. These bulletins stated that the track forecast for Hurricane Joaquin was highly uncertain and had two scenarios. Hurricane Joaquin was a very significant forecast challenge for the NHC and for forecasters in Atlantic Canada. There were two distinct track scenarios for Joaquin early on in its development. If Hurricane Joaquin were to make landfall in the United States, moisture from the storm could lead to heavy rainfall in southern Ontario and southern Quebec where the ground was already saturated from a previous heavy rain event. However, if Joaquin were to track away from the east coast of the United States and well south of Atlantic Canada, impacts to Canadian land territory would be limited to large swell waves at the coastlines. On October 2nd, the second track scenario became increasingly more likely. Therefore, the two bulletins issued by the CHC stated that such an offshore track would give minimal impact to land areas in Canada and would not require subsequent bulletins from the CHC. Coordination and Communications Efforts There was considerable coordination between the head of CHC operations, ASPC and NLWO on Joaquin. This coordination was based on conditions expected over southern marine areas and southern coastlines. In addition, all parties were involved in the decision to not issue regular products on this storm from the CHC. Joaquin generated moderate media coverage in Canada due to its significant impacts in the Caribbean. Directory: pages -> prog -> www -> tcp -> linkedfiles linkedfiles -> Regional Association IV (North America, Central America and the Caribbean) Hurricane Operational Plan linkedfiles -> Regional Association IV (North America, Central America and the Caribbean) Hurricane Operational Plan linkedfiles -> Review of the past hurricane season summary of the past season linkedfiles -> Review of the past hurricane season summary of the past season linkedfiles -> Hurricane Fay, 11-12th October linkedfiles -> World meteorological organization linkedfiles -> Cyclone programme linkedfiles -> Review of the past hurricane season linkedfiles -> World meteorological organization Download 26.18 Kb. Share with your friends:
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