August 5 downburst at Tilley, AB rated EF1

NTP investigation, including an NTP ground/drone survey, has resulted in the confirmation of a downburst at Tilley, AB during the late evening hours of August 5. A storm resulted in significant damage to several agricultural structures as well as tree damage. The downburst winds were from the SW through WNW. The worst of the damage was rated EF1 on the EF scale.

Details are provided below, as well as maps and photos. The event can be plotted on a map via the NTP Dashboard here.


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Event Name: Tilley, AB

Date: August 5, 2024

Start Time: 11:00 PM MDT (0500 UTC) 

Final Classification: Downburst

Final EF-Scale Rating: EF1

EF-Scale Damage Indicator / Degree of Damage: SBO/DOD-4

Location of worst damage: 50.4083N, 111.7748W

Description: Structural damage was reported in the Tilley area after a storm passed through. No injuries were reported. An NTP ground and drone survey was completed on August 12, 2024, documenting the reported damage and discovering additional structural and tree damage along the storm track, including moderate damage to a barn roof southwest of Tilley. Intermittent damage was documented over an area approximately 21.1 km long and up to 8.7 km wide from the eastern shore of Lake Newell to south of Tilley. Damage assessed as EF1 downburst, with an estimated max. wind speed of 145 km/h. Start time is radar estimated. Satellite imagery review revealed some signs of structural damage.
 

TilleyRegMap.png
Regional map showing the location and rating of the downburst at Tilley, AB.

TilleySurveyMap.png
Survey map showing the extent of the EF1 downburst and the locations of ground and drone photos.


TilleyDmg1.jpg
Drive shed with roof thrown and most walls down.


TilleyDmg3.jpg
Farm outbuilding building was severely damage, with flying debris causing the failure of concrete stave silo.


TilleyDmg2.jpg
Warehouse building with roof damage.