History with Hailstorm Reduction

Extreme weather conditions like hail and thunderstorms are common during summer months in Alberta. These storms cause significant damage as we saw during the Calgary hailstorm on August 5th, 2024, which caused $2.9 billion in insured damages. While hail damage can be covered if you purchase comprehensive insurance, this type of insurance is an optional addition, and submitting a claim may cause your premiums to increase.

The damage caused by hailstorms is often lessened due to cloud seeding.  Studies on cloud seeding were first conducted in 1956 to 1985 by the Alberta Research Council, and following a destructive Calgary hailstorm in 1991, the Alberta Severe Weather Management Society was established to use cloud seeding to reduce large and destructive hail from falling in Red Deer and Calgary areas.

What is Cloud Seeding?

Hail is formed when water droplets are carried up by winds to high levels of the atmosphere with freezing temperatures. Cloud seeding is a process using silver iodide to prevent these hailstones from growing too large and causing more severe damage when falling during a storm. The process does not stop or create hailstorms, it modifies existing ones.

Silver iodide particles attract water droplets in a cloud and create many small hailstones instead of a few large ones at lower temperatures. While normal hail starts forming at -15°C to -20°C, adding silver iodide allows hailstones to start freezing at -5°C, lower in the atmosphere, so they the hail stones do not grow as big or fall from as high.

The basic steps to cloud seeding are:

1. Silver iodide is released by a plane to a targeted storm cloud.  Flares on the wings of planes seed the bottom of a storm, while canisters below the aircraft seed the top of a storm cloud.
2. The reaction forms ice crystals in the cloud.  Many smaller hailstones are created at lower atmospheric temperatures.
3. Enough small ice crystals are produced that they eventually fall from the cloud.  Their small size often allows them to melt into raindrops on their way down.

This process reduces the amount of large hailstones falling, therefore reducing the amount of severe damage from hailstorms. Cloud seeding operations run from June 15th to September 15th every year, which is peak hailstorm season.

Who is Responsible for Cloud Seeding?

Cloud seeding takes place each year due to the Alberta Hail Suppression Project, which costs approximately $5 million per year to operate. The project is primarily paid by insurance companies, based on market share, through the Alberta Severe Weather Management Society. The project is supported by a team of meteorologists who are responsible for seeding threatening hailstorms 24/7 and uses 5 twin-engine aircrafts flying out of the Springbank and Red Deer Regional Airports to seed hailstorms in the Red Deer and Calgary area. The radar used by the team is available to the public at https://www.wmiradar.com/ahsp/.

What can YOU do to reduce hail damage during a storm?

There are several things a vehicle owner can do to prevent or reduce damage during a storm.

• Park in garage or covered area whenever possible. If you are driving during a storm leave the road and seek shelter in a safe, covered area (i.e. gas station or parkade)
• Monitor the weather forecast so you can be prepared when a hailstorm is coming
• AVOID parking under trees: falling branches can cause further damage
• Use blankets or mats to cover your car
• Invest in hail-resistant materials for your car
• Install protective covers or portable shelters
• Consider comprehensive insurance so you are covered for damage