For the second time in less than five years, Calgary, Alta. was hit by a violent hailstorm on Monday, Aug. 5. Western's Northern Hail Project (NHP) was collecting data on the day of the storm and, because of the extensive damage, is now leading Canada's first ever in-depth investigation of a major urban hail event.
NHP field teams, still conducting forensic-level damage surveys across affected areas of Calgary, collected data on the storm in real time as part of ongoing research into hailstorms in Canada. Investigators have already shared detailed data with colleagues from the Insurance Institute for Business & Home Safety (IBHS) in Richburg, SC.
Preliminary findings indicate that the scope of damage for this event is like that from the 2020 storm. The main difference being that this time the International Airport (and aircraft on the ground) sustained noteworthy damage.
Based in Olds, Alta. for a summer field study as part of a five-year strategy, NHP and its research partners, Western's Institute for Catastrophic Loss Reduction (ICLR) and the University of Manitoba, are studying damaging hail impacts across the province.
"The unique dataset from the 2024 Calgary event will help inform better building standards and will be used to improve forecast products, as well as our understanding of why some hailstorms produce significant amounts of large hail and/or hail accompanied by strong winds," said Julian Brimelow, NHP executive director.
NHP is still determining the extent of the hail damage and the largest size of hail; so far evidence has been found of ping-pong to golf-ball-sized hail.
Damage surveys ongoing
The storm formed to the west of Cochrane, Alta. around 5:15 pm MT on Aug. 5 and passed over Calgary, Alta. between 7:45 and 8:30 pm MT, causing widespread, severe hail damage.
NHP has learned the hailswath was more than 120 km long and 12 km wide. Strong winds also seemed to play a role in increasing damage.
NHP has successfully completed the installation of 20 hail disdrometers - all accompanied by weather stations - within Calgary's city limits, plus one in Airdrie, Alta., just north of the city. Ten of these stations were hit by hail and indicated that a large amount of 30-mm diameter hail fell in their vicinity.
Fifteen NHP investigators, including Western engineers, faculty, staff and student interns divided into four teams, are currently participating in damage survey efforts. They run both ground surveys and aerial surveys using unpiloted aerial vehicles (UAVs). The investigation is expected to last until Aug. 10 at least.
NHP aims to improve knowledge of damaging hailstorms and the detection of hail across Canada. It also hopes to improve severe convective storm prediction, mitigate against harm to people and property and investigate future implications due to climate change.
NHP is a research spinoff of the Northern Tornadoes Project, which was founded in 2017 with support from social impact fund ImpactWX.