Long path of downburst damage through Legal, AB on July 31
NTP investigation has documented as long path of EF0 damage through Legal, AB on July 31. A bow echo-type storm felled trees and removed shingles along a path 155 km long and 17 km wide, with the storm producing a cluster of damaging downbursts. A large event tent near Busby was destroyed injuring more than 50 and resulting in 1 fatality.
Full details are provided in the event summary below, as well as a survey map, survey images and radar. The event can be plotted on a map using the NTP Dashboard .
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Event Name: Legal, AB
Date: July 31, 2024
Start Time: near 4:30 PM MDT (2230 UTC)
Final Classification: Downburst
Final EF-Scale Rating: EF0
EF-Scale Damage Indicator / Degree of Damage: FR12/DOD-2
Start of damage track: 54.00N, 114.69W
End of damage track: 53.86N, 112.34W
Location of worst damage: 53.952N, 113.597W
Description: Witnesses captured photos and video of damaging winds in the affected area. A large event tent near Busby was destroyed injuring more than 50 and resulting in 1 fatality. An NTP ground survey was completed on August 1-2 documenting the reported damage and extending the known path. Satellite imagery was able to reveal only isolated tree and crop damage along the path. Damage assessed as EF0 downburst cluster, with an estimated max. wind speed of 125 km/h, damage path length of 155 km and max. path width of 17 km. The path was oriented from west to east (approx. 275 degrees). Time based on radar.
Regional map showing the location of the worst damage associated with the Legal, AB EF0 downburst.
Survey map showing the locations of documented damage along the damage path north of Edmonton, AB.
Worst documented damage at Legal, AB with numerous roof shingles removed a house. Other houses in the area also had shingles removed.
Multiple trees snapped along Range Road 15A north of Busby, AB, near the location where the large tent collapse occurred.
IW Pro image from Environment Canada's CASCV radar showing the bow-echo type storm passing Busby, AB and approaching Legal, AB, north of Edmonton. Radar reflectivity is shown at left while Doppler radial velocity is shown at right.
