Thunderstorms are always happening.
If it is not happening near you right now, there are approximately 2,000 thunderstorms in progress around the world at this very moment.
Heavy raindrops beat the roof, lightning flashes through the windows, and a loud clap of thunder booms. Each year, there are an estimated 16 million thunderstorms each year worldwide. Thunderstorms generally last only for a short period of time. Yet, their common association with lightning, thunder, dense clouds, heavy rain or hail, and strong gusty winds can cause enormous damage in seconds.
SCIENCE & ANATOMY OF THUNDERSTORMS
Thunderstorms form when moist, warm air rise into cold air. When the warm air cools down, it forms water vapor to form small water droplets. This process is called condensation. The cooled air drops lower in the atmosphere, gets warmed, and rises again. The repeat of this circuit of air rising and falling is called a convection cell. If this only happens in a small amount, it will form a cloud. On the other hand, if this happens with large amounts, a thunderstorm can form.
Thunderstorms can consist of just one convection cell or multiple convection cells. Having just one convection cell does not always guarantee a mild thunderstorm. One very large and extremely powerful conviction cell cause Supercell Thunderstorms, the largest, longest, and most damaging type. Destructive thunderstorms can bring deep, rotating updraft winds, huge amounts of rain, and hail as big as baseballs.
Because Thunderstorms can be extremely dangerous, governments release weather advisories to warn citizens ahead of time. In order to plan and take appropriate actions, it is vital to understand what different advisories mean and what to do accordingly. Please note that the criteria for watches and warnings vary throughout Canada and the United States; as a result, a warning may be issued in certain areas, not others.
WEATHER OF CONCERN
When an active thunderstorm is expected or occurring, but there's no clear indication that conditions will be severe at the moment, a governmental body (ex. Environment Canada) issues a Special Weather Statement, especially in regards to thunderstorm This is to let the public know that there is a weather of concern that a region may soon experience.
Severe Thunderstorm Watch
This is issued when the weather conditions are favorable for the development of severe thunderstorms in/near the watch area. In most cases, severe thunderstorm watches are issued for four to eight hours, well in advance of the actual occurrence of severe weather conditions.
A thunderstorm is classified as “severe” with the potential to produce one or more of the following:
Wind gusts of at least 90 km/h (50 knots or 57.5 mph)
Hail of at least two centimeters in size
Heavy rainfall, as above
Hail, strong wind, and possible flooding from severe thunderstorms can pose a significant risk of injury and potential damage to property.
What to do:
Continue to listen/watch weather news to stay updated about severe thunderstorm watches and warnings.
Review severe thunderstorm safety rules
Be prepared to move to a place of safety if threatening weather continues to approach
Severe Thunderstorm Warning
A warning is issued either when either a severe thunderstorm is indicated by radar or a spotter reports a thunderstorm producing hail one inch or larger in diameter and/or winds equal to or exceed 93km/h (58 miles/h). Severe thunderstorms can cause significant destruction to property and possible injuries to people in the affected area. They can produce also tornadoes with little or no advance warning. Severe thunderstorm warnings are usually issued for a duration of one hour in general.
What to do:
If you are indoors
Stay away from windows, skylights, and glass doors.
Avoid running water in your house. Don't take showers or baths during a thunderstorm.
Remain indoors during a thunderstorm. It is strongly advised to continue to stay inside for at least 30 minutes after the last rumble of thunder.
If the weather condition worsens, seek shelter in a basement or interior room on the lowest level.
If you are outdoors
A good rule of thumb for everyone is: 'If you can see it (lightning), you need to must flee it. If you can hear it (thunder), you must clear it.' Continue to read for more detailed information.
ESSENTIAL SAFETY TIPS FOR THUNDERSTORMS
General Rules:
Suspend all activities when lightning is 9 km (6 miles) away.
Avoid trees, poles, and any other objects that are tall. they can attract lightning.
Do not go near wet areas.
Go into a large, permanent building.
In the worst-case scenario where sudden, close-in lightning does not allow you to take immediate evacuation to a safer place, spread out from your group. Squat, tuck your head, and cover your ears. Run to the safest place as soon as the immediate threat passes by. Never lie flat on the ground during a thunderstorm; crouch down as low as possible.
Golfers are Especially Vulnerable to Lightning
Because golf is played in a wide-open area and golf clubs are metal, golfers are very vulnerable to lightning during a thunderstorm. If a thunderstorm happens when you are on a golf course, never touch any metal objects including golf clubs, fences, and electrical machinery.
If You are in Any Body of Water
Being in a body of water (including a pool, a lake, and the ocean) during a thunderstorm is extremely dangerous because water is a natural conductor of electricity. Therefore, you must leave the water and seek shelter immediately at the first sign of the thunderstorm. Lightning strikes to the ground anywhere on the metallic network of swimming pools (water pipes, gas lines, electrical wirings, etc.)may induce electrical shocks elsewhere. Don't go back to the water immediately after the storm passes. Stay away from water at least 30 minutes after the last thunder is heard.
If You are in a Car
Cars can be a good shelter. If you are outside at a picnic or camping, getting to your car if another shelter is unavailable nearby can be a good option. However, there are cars that are not safe during thunderstorms.
A safe vehicle is any vehicle that is fully enclosed and metal-topped. Hard-topped cars, minivans, trucks, and buses are all safe. On the other hand, vehicles that are not fully enclosed are not safe. Convertibles, open cab construction equipment, golf cars, riding mowers, and even boats without cabins are all dangerous.
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