How does NTP detect and characterize tornadoes?

NTP has a multi-step process for detecting, characterizing and documenting tornadoes.

Field teams are trained and ready to respond at a moment's notice. Tornado potential outlooks are created by NTP and sent to the teams to ensure they are prepared. Once potentially tornadic storms occur, they are tracked using available radar. NTP follows up on any reports of wind damage or visual sightings of tornadoes (usually via social media).

Ground survey teams are deployed once an area of potentially tornadic damage has been identified. The team will also typically collect drone imagery (resolution less than 2 cm) in the area of interest. While ground surveying activities are underway, other team members scour satellite imagery (resolution 3-5 m) to map out the extent of damage and determine if other unreported damage exists nearby.

In events with significant damage that cannot be fully sampled by drone, aircraft-based aerial imagery (resolution 5 cm) is collected usually some time after the event. A preliminary classification (typically tornado or downburst) and rating (using the EF-scale) is usually determined shortly after the event in coordination with Environment and Climate Change Canada.

However, NTP then undertakes a more thorough investigation incorporating all collected data to determine a final classification and rating. This typically takes from weeks to months, depending how quickly all data are received and analyzed.