Self-Help Advice for Families and Individuals
Severe Storms

Contents Introduction Listen for the warnings Be prepared When a severe storm is forecast Things to do after the storm Tornadoes Severe thunderstorms Winter storms Hurricanes Mobile homes Additional information

Introduction

Thunderstorms, tornadoes, hail, blizzards, high winds and heavy rain can develop quickly and hit hard, posing a threat to life and property.

If you are like most Canadians you have probably had to clean up after these storms and you know the damage they cause. Some problems cannot be prevented. High winds will topple trees and heavy rains will cause rivers to flood. But some damage can be avoided, or at least reduced, if you take a few simple precautions such as knowing the type of storms common to your area and what time of year they are likely to strike.

The purpose of this document is to help you prepare for severe weather by listing a few steps which you can take to protect your family, yourself and your property when a severe storm hits your area.

Listen for the warnings
Environment Canada monitors the weather 24hours a day, seven days a week. If a severe storm is on the horizon, the weather service issues watches, advisories and warnings through national, regional and local radio and television stations, as well as Environment Canada's Weatheradio.

• Weather watch
  Conditions are favourable for a severe storm, even though one has not yet developed. This is usually issued early in the day. Keep monitoring weather conditions and listen for updated statements.
  
  
• Weather warning
  Severe weather is happening or hazardous weather is highly probable.

If a weather warning is issued for a tornado, it means that one or more tornadoes have been observed or are forecast for the specified area. Other warnings include those for a severe thunderstorm, blizzard, high winds, heavy snow, snow squall, heavy rain and significant freezing rain.

Be prepared

Storms such as tornadoes often strike too quickly to allow you to choose a shelter or to pack an emergency kit. You may want to have a plan that outlines where you will go and how you will keep in touch with members of your family if a severe storm hits. Municipal, provincial and territorial emergency management organizations can provide valuable advice to help you prepare for emergencies.

Choose your shelter area
A basement, storm cellar or a closet beneath the stairs are good places to take shelter in the event of a severe storm. If none of these is available, sit underneath a sturdy piece of furniture on the ground floor in the centre of the building, away from the outside walls and windows. Be sure you discuss the shelter area with your family ahead of time.

Pack an emergency kit
This should include food, clothing, blankets, medication, water-purification tablets and first aid and tool kits, as well as flashlights and a battery-powered radio -- with extra batteries for both.

Reduce the hazards
Trim dead or rotting branches and cut down dead trees to reduce the danger of these falling onto your house. You may also want to consider checking the drainage around the house to reduce the possibility of basement flooding after a heavy rain.

Choose a place to meet
When a severe storm strikes, members of your household may be at work, school or a friend's place. To avoid unnecessary worry, plan a meeting place or some system of communicating with one another to check that everyone is safe.

When a severe storm is forecast
Severe weather can occur any time of the year, winter or summer. Make it a habit to listen to the local radio or television stations for severe weather warnings and advice. Make sure you have a battery-powered radio on hand; electricity frequently fails during a severe storm.

Secure everything that might be blown around or torn loose -- indoors and outdoors. Flying objects such as garbage cans and lawn furniture can injure people and damage property. If hail is forecast, you may want to protect your vehicle by putting it in the garage.

Never venture out in a boat. If you are on the water and you see bad weather approaching, head for shore immediately. Always check the marine forecast before leaving for a day of boating and listen to weather reports during your cruise.

If you are outdoors when a storm hits, take shelter immediately. If you are advised by officials to evacuate, do so. Take your emergency kit with you.

Stay calm. You will be better able to cope with emergencies.

Give first aid to people who are injured or trapped. Get help, if necessary.

Unless you are asked to help or are qualified to give assistance, please stay away from damaged areas.

Do not go near loose or dangling power lines. Report them and any broken sewer and water mains to the authorities.

Lightning and downed power lines can cause fires. Report fires to the fire department. Know how to fight small fires.

Water supplies may be contaminated, so purify your water by boiling it for 10 minutes, by adding water-purification tablets or by adding one drop of unscented chlorine bleach to one litre of water (or three drops for cloudy water).

If you use chlorine bleach to purify the water, stir the bleach in and wait 30 minutes before drinking. The water should have a slight chlorine smell.

Please leave the telephone lines free for official use. Do not use the telephone except in real emergencies.

Drive cautiously and only if necessary. Debris, broken power lines and washed-out or icy roads and bridges will make driving dangerous after a severe storm. Please give way to emergency vehicles at all times.

Finally, if the power has been off for several hours, check the food in the refrigerator and freezer in case it has spoiled.

Tornadoes
Tornadoes form suddenly -- often preceded by warm, humid weather -- and are always produced by thunderstorms, although not every thunderstorm produces a tornado. There are warning signs, including:

• severe thunderstorms, with frequent thunder and lightning
• an extremely dark sky, sometimes highlighted by green or yellow clouds
  
• a rumbling sound, such as a freight train might make, or a whistling sound, such as a jet aircraft might make
  
• a funnel cloud at the rear base of a thundercloud, often behind a curtain of heavy rain or hail.

Tornadoes are violent windstorms characterized by a twisting, funnel-shaped cloud which forms at the base of cloud banks and points towards the ground. Tornadoes usually move over the ground at anywhere from 20 to 90 kilometres per hour and often travel from the southwest to the northeast. They are erratic and can change course suddenly. It is not a good idea to chase tornadoes.

Generally speaking, May to September are prime tornado months. Tornadoes usually hit in the afternoon and early evening but they have been known to strike at night too.

Canada has several high-risk areas, including Alberta, southern Ontario, southern Quebec and a band of land which stretches from southern Saskatchewan and Manitoba through to Thunder Bay, Ontario. There are also tornado zones in the interior of British Columbia and in western New Brunswick.

Things to do in case of a tornado

• If you live in one of Canada's high-risk areas, you should listen to your radio during severe thunderstorms. As a rule, when Environment Canada issues a tornado warning, radio stations broadcast it immediately. If you hear that a tornado warning has been issued for your area, take cover immediately.
  
  

• If you are at home, go to the basement or take shelter in a small interior ground floor room such as a bathroom, closet or hallway. Failing that, protect yourself by taking shelter under a heavy table or desk. In all cases, stay away from windows, outside walls and doors.
  

• If you are in an office or apartment building, take shelter in an inner hallway or room, ideally in the basement or on the ground floor. Do not use the elevator and stay away from windows. Avoid buildings such as gymnasiums, churches and auditoriums with wide-span roofs. These roofs do not have supports in the middle and may collapse if a tornado hits them. If you are in one of these buildings, take cover under a sturdy structure.

• Do not get caught in a car or mobile home. More than 50 per cent of all deaths from tornadoes happen in mobile homes. Take shelter elsewhere -- such as a building with a strong foundation. If no shelter is available, lie down in a ditch away from the automobile or mobile home. However, beware of flooding from downpours and be prepared to move.

• If you are driving and spot a tornado in the distance, try to get to a nearby shelter. If the tornado is close, get out of your car and take cover in a low-lying area. If a tornado seems to be standing still, then it is either travelling away from you or heading right for you.

• In all cases, get as close to the ground as possible, protect your head and watch out for flying debris. Small objects such as sticks and straws can become lethal weapons when driven by a tornado's winds.
  

Lighting
The air is charged with electricity during a thunderstorm. The most striking sign of this is lightning. Bolts of lightning hit the ground at about 40,000 kilometres per second -- so fast that the lightning appears to be a single main bolt with a few forks, when actually the opposite is true. The main bolt is a whole series of lightning strikes, all taking the same path but at such a pace that the eye cannot distinguish between them.

To estimate how far away the lightning is, count the seconds between the flash of lightning and the thunderclap. Each second is about 300 metres. If you count fewer than 30 seconds, look around for shelter; if fewer than five seconds, take shelter urgently. Lightning is near and you do not want to be the tallest object in the area. It is recommended to wait 30 minutes after the last lightning strike in a severe storm before venturing outside again.

At the office or at home

• If indoors, stay there, but away from windows, doors, fireplaces, radiators, stoves, sinks, bathtubs, appliances, metal pipes, telephones and other materials which conduct electricity. (You can use a cellular telephone.)
• Unplug radios and televisions.
• Do not go out to rescue the laundry on the clothesline, as it conducts electricity.

Outside

• Take shelter, preferably in a building; failing this, in a depressed area such as a ditch or a culvert, but never under a tree.
  
• Do not ride bicycles, motorcycles and golf carts -- or use metal shovels and golf clubs -- as they conduct electricity.
• If swimming or in a boat, get back to shore immediately.
  
• If caught in the open, do not lie flat but crouch in the leapfrog position and lower your head.
  
• If you are in a car, stay there but pull away from trees where heavy branches might fall on you.
  

Heavy rain
A heavy rainfall can result in flooding. This is particularly true when the ground is still frozen or already saturated from previous storms. Floods may also result if a heavy rain coincides with the spring thaw.

• If you know there is flooding or the possibility of flooding in your area, keep your radio on to find out what areas are flooded, what areas are likely to be flooded, as well as what roads are safe, where to go and what to do if the local emergency team asks you to leave your home.
  
  
• Generally speaking, it is a good idea to avoid driving through flooded roads and underpasses. The water may be a great deal deeper than it looks and you could get stuck. You may also want to avoid crossing bridges if the water is high and flowing quickly.
  

Hail
Hail forms when updrafts in thunderclouds carry raindrops upwards into extremely cold areas of the atmosphere. The raindrops freeze and are bounced around in the powerful winds within thunderclouds while new layers of ice are added. Eventually, the hailstones grow too heavy to be supported by the updrafts and fall to the ground. Some hailstones are the size of peas while others can be as big as grapefruits.

Take cover when hail begins to fall. Do not go out to cover plants, cars or garden furniture or to rescue animals. Hail comes down at great speed, especially when accompanied by high winds. Although no one in Canada has ever been killed by hail, people have been seriously injured by it.

Freezing rain occurs when an upper air layer has an above-freezing temperature while the temperature at the surface is below freezing. The snow that falls melts in the warmer layer; as a result, it is rain -- not snow -- that lands on the surface. But since the temperature is below 0°C, raindrops freeze on contact and turn into a smooth layer of ice spreading on the ground or any other object like trees or power lines. More slippery than snow, freezing rain is tough and clings to everything it touches. A little of it is dangerous, a lot can be catastrophic.

In Canada, blizzards are most common in the Prairies and the eastern Arctic. Heavy snowfalls are most common in British Columbia, areas around the Great Lakes, southern and eastern Quebec and the Atlantic provinces. Freezing rain can occur pretty much anywhere in the country but is particularly common from Ontario to Newfoundland.

On average, the storms and cold of winter kill more than 100 people every year. That is more than the total number of people killed by hurricanes, tornadoes, floods, lightning and extreme heat.

At home
If you live in a community located in one of the areas where blizzards or heavy snows are frequent, you may want to consider stocking up on heating fuel and ready-to-eat food, as well as battery-powered flashlights and radios -- and extra batteries.

• When freezing rain, heavy snow, blowing snow or a blizzard is forecast, leave your radio on to stay informed of the situation and hear updated forecasts.
  
  
• If a blizzard or heavy blowing snow is forecast and if you are on a farm with livestock, bring the animals into the barn. Make sure they have plenty of water and food. You may also want to string a lifeline between your house and any outbuildings to which you may have to go during the storm.
  
  
• When a winter storm hits, stay indoors. If you must go to the outbuildings, dress for the weather. Outer clothing should be tightly woven and water-repellent. The jacket should have a hood. Wear mittens -- they are warmer than gloves -- and a hat, as most body heat is lost through the head.
  
  
• In wide open areas, visibility can be virtually zero during heavy blowing snow or a blizzard. You may easily lose your way. If a blizzard strikes, do not try to walk to another building unless there is a rope to guide you or something you can follow.
  
  
• Ice from freezing rain accumulates on branches, power lines and buildings. If you must go outside when a significant accumulation of ice has already occurred, pay attention to branches or wires that could break, due to the weight of the ice, and fall on you. Ice sheets could also do the same. Above all, do not touch power lines: a hanging power line could be charged (live) and you would run the risk of electrocution. Remember also that ice, branches or power lines can continue to break and fall for several hours after the end of the precipitation, so be vigilant.

Finally, if the power has been off for several hours, check the food in the refrigerator and freezer in case it has spoiled.

• See also: Winter Power Failures
  

In your car
As a rule, it is a good idea to keep your gas tank almost full during the winter and to have extra windshield washer fluid and antifreeze on hand. You may want to prepare two small emergency kits -- one to put in the trunk of your car and the other in the cab of the car.

The trunk kit should include:

• shovel, sand, or salt, kitty litter or other traction aids
  
• tow chain and booster cables
  
• fire extinguisher, warning light or flares
  
• extra clothing, including mittens, hats and boots.

The kit in the cab of the car should include:

• flashlight
  
• blanket
• first-aid kit
  
• matches, candles (in a deep can to warm hands or heat a drink) and emergency food pack.

If you do not already have a cellular telephone and if the cellular network works in your area, you may want to consider having one with you in your car for emergencies.

Remember that freezing rain, even just a little freezing rain, can make roads extremely slippery. Driving is not recommended when freezing rain is forecast, or for several hours after freezing rain ends, so that road maintenance crews have enough time to spread sand or salt on icy roads.

If you must travel during a winter storm, do so during the day and let someone know your route and arrival time.

If your car gets stuck in a blizzard or snowstorm, remain calm and stay in your car. Allow fresh air in your car by opening the window slightly on the sheltered side -- away from the wind. You can run the car engine about 10 minutes every half-hour if the exhaust system is working well. Beware of exhaust fumes and check the exhaust pipe periodically to make sure it is not blocked with snow. (Remember: you can't smell potentially-fatal carbon monoxide fumes.)

Finally, to keep your hands and feet warm, exercise them periodically. In general, it is a good idea to keep moving to avoid falling asleep. If you do try to shovel the snow from around your car, avoid overexerting yourself, as shovelling and bitter cold can kill. Keep watch for traffic or searchers.

• See also: Winter Driving
  

Hurricanes
Hurricanes are violent tropical storms which blow up from the Caribbean and occasionally hit eastern Canada, usually between June and November, with September being the peak month. The east and west coasts, however, do get fall and winter storms which have hurricane-force winds. Hurricanes cause more widespread damage than tornadoes because they are bigger. Some are as large as 1,000 kilometres across.

If a hurricane warning has been issued and you live on the coast or in a low-lying area near the coast you are advised to move inland and to higher ground. The high winds create huge waves at sea which, when they reach the shore, may become tidal waves or storm surges.

Do not go down to the water to watch the storm. Most people who are killed during hurricanes are caught in large waves, storm surges or flood waters.

As a rule, hurricanes move slowly and batter communities for several hours. If the eye of the hurricane passes over, there will be a lull in the wind lasting from two or three minutes to half an hour. Stay in a safe place. Make emergency repairs only and remember that once the eye has passed over, the winds will return from the opposite direction -- with possibly even greater force.

Mobile homes
Owners and residents of mobile homes must take special care to protect themselves and their property in the event of storms.

Position your trailer near a natural windbreak such as a hill or clump of trees. As severe storms usually come in from the southwest, west or northwest, the narrow end of the trailer should face in a westerly direction to make a smaller target.

Make sure your trailer is securely anchored. Consult the manufacturer for information on secure tie-down systems.

Finally, when a severe storm approaches, you should still seek shelter in a more secure building. Trailers are the exception to the stay-indoors rule.

Additional information

Produced in cooperation with Environment Canada

Please contact your provincial/territorial emergency management organization (EMO) for regional or local information on emergency preparedness.
For general information or to order our self-help brochures, please contact us.

• See also: Natural Hazards of Canada and the Canadian Disaster Database.
  

ISBN 0-662-30879-4
Catalogue No. D82-27/2001-1E
© Minister of Public Works and Government Services
Revised June 2003