Thunder storms are a common event all over Alberta in June, when towering cumulonimbus clouds gather. These are huge amounts of water vapor carried upwards by powerful air currents rising from below.
These clouds cool rapidly when they reach heights of as much as 20 kilometres / 12 miles. Hence the tiny water droplets often turn to ice, and grow larger as gravity pulls them lower before an updraft sends them high up again.
How Climatologists Predict Hailstorms over Calgary
Once a hailstone reaches a certain size and weight, gravity overcomes the updrafts and it falls to the ground. Weather scientists are able to predict this by using weather satellites, and weather radar imagery. The latter locates precipitation, calculates its motion, and estimates whether it is rain, snow, sleet, or hail.
However, this is not an exact science, because hailstones melt as they fall due to friction with the air and wind, and interaction with rain and other hailstones. Hence, severe hail warnings may understate or overstate the risk to crops and homes.
Did You Know Calgary is the ‘Hailstone Capital of Canada’?
Our forefathers dug the first foundations of our city in the most hail-intensive part of Canada. ‘Hailstorm Alley’ is not a narrow thoroughfare though. It stretches from High River in southern Alberta, northward through Calgary, through Red Deer to Lacombe and then westward to Rocky Mountain House.
However the boundaries to “one of the worst areas in the world for damaging hail produced by thunderstorms” are porous according to Wings Magazine. That’s because the whole of central and southern Alberta experiences hailstorms annually.
How Global Warming Will Increase Their Severity
The authoritative journal Nature Climate Change predicts the severity of hailstorms will increase across the central and central-western parts of North America, as global warming bites. That’s because while small hailstones will melt before they reach the ground, larger ones will become even bigger owing to stronger updrafts.
You should take these trends into account if you are considering renovating or upgrading the exterior of your home in Calgary, The days of soft metals are passing rapidly. You should consult an expert such as Valiant Exteriors before finally deciding on your finishes.
Preview: Average Annual Hail Frequency in Southern Canada (Image AIR CROP)