Sunday, 31 January 2016

At least two tornadoes touched down in Forbes Creek, NSW and Reservoir, VIC on Saturday 30 January 2016, with a possible third tornado occurring at Palmers Island, NSW.

Forbes Creek, New South Wales.

Damage shown in pictures and videos indicate winds consistent with EF2 intensity tornado. The video posted by Stormspotters AU (below) shows large areas of EF1 damage. There are three damage points that are indicative of an EF2 tornado in the video. At 4'35" the house has lost large sections (if not all) of its roof structure, but most walls remain standing. This degree of damage to family residence indicates winds 165-225 km/h with an expected intensity of 195 km/h. At 4'38" and 9'40" two separate hardwood trees appear to have been partially debarked. This degree of damage to a hardwood tree indicates winds 195-265 km/h with an expected intensity of 225 km/h.


Damage detailed in articles by the ABC and Sydney Morning Herald show the same degree of destruction to a second family's home. These four points of evidence (particularly the structural damage) lead to the conclusion that the winds contained in this tornado peaked at about 195 km/h.

The home of Geoff and Jan McKergow at Forbes Creek was all but destroyed by Saturday night's storm.
ABC News: James Fettes

A map showing the damage path tweeted by Queanbeyan City RFB show a trail of destruction approximately 3.75 km long, with reports that the path was approximately 100 meters wide.

Image Credit: Queanbeyan City RFB.
Tornado damage path Forbes Creek, trees felled in multiple directions. Image credit: Queanbeyan City RFB.
Canberra (Captains Flat) Rain Rate Radar 23:36 EDT 30/01/2016 - arrow indicates dip in radar intensity.
Base Image Credit: weatherzone.com.au
Canberra (Captains Flat) Rain Rate Radar 23:36 EDT 30/01/2016 - line indicates interpretation indicating potential hook echo around dip in radar intensity. Base Image Credit: weatherzone.com.au

The Canberra (Captains Flat) Doppler Radar shows a mesocyclone passing directly over Forbes creek at 11:36 PM (23:36 EDT). This is accompanied by a potential hook echo that can be observed on the Rain Rate Radar image at the same time.

Canberra (Captains Flat) Doppler Wind Radar 23:24 EDT 30/01/2016 to 00:06 EDT 31/01/2016 - arrows indicate mesocyclone. Images chronological left top to bottom then, right top to bottom at 6 minute intervals.
Base Image Credits: weatherzone.com.au

Reservoir, Victoria.

As reported by 7 News Melbourne, a tornado impacted parts of Reservoir on Saturday night. Damage in pictures of the aftermath indicates the tornado was of at least EF0 intensity, packing winds in excess of 100 km/h.

Melbourne Radar, Rain Rate 23:24 EDT (left) and Doppler Wind 23:25 EDT (right) 30/01/2016
Circles indicate possible hook (left), and the mesocyclone (right). 
Base Image Credit: weatherzone.com.au

Doppler radar shows a mesocyclone and possible hook echo passing over the area at the time that CCTV footage (7 News Report) shows the tornado impacting the area at 11:24 PM (23:24 EDT).

Palmers Island, New South Wales.

The damage at Palmers Island is indicative of at least an EF1 intensity tornado, but as no images of the actual tornado exist, nor is there a high resolution Doppler Radar in the area to provide evidence to support the hypothesis, it is probable that this was a tornado but can not be confirmed. Damage indicates winds of at least 165 km/h.

Storm damage at Palmers Island, NSW Coast. ABC: Debrah Novak
Wind speeds in this post are conservative estimates calculated from the damage observed using the Enhanced Fujita (EF) Scale.

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