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20th January 2005 - Storm outbreak

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Michael Thomas:
The day of the Coonabarabran tornado. See below for info on the tornado and model analysis/satellite images-

http://www.australiasevereweather.com/storm_news/2005/docs/200501-04.htm

Early development west of Marulan. Nice structure with good updraft/downdraft seperation. I suspect this later developed into the storm that moved through the Berry region. I left this storm for stronger storms further south-


Hail at Lake Bathurst, I arrived just after the main storm and was hit by small (0.5 - 1 cm) hail from a seperated storm-


Tree damage west of Berry on the road that heads to Kangaroo Valley. These photos were taken several days after the event-





Sydney radar loop (note, I did not make this gif file, I downloaded it from another website many years ago)-


Damage west of Berry seems to coincide with a strong storm merging with another storm to its north. This then forms into what appears to be a HP supercell which moves out to sea south of Kiama. Another supercell develops to the NW of this storm which then moves directly over Kiama. The radar presentation of the later supercell is very nice. I would have to think that the damage west of Berry was caused by straight-line winds. The damage path width is relatively wide and the damage is not very severe (for a tornado anyway). Also, most of the damage seems to indicate strong westerly or south-westerly winds. Though, I suppose a tornado can't be ruled out.

Michael

Jimmy Deguara:
Hi Michael,

I cannot tell either way. The storm on radar seems to deviate into an easterly direction and slowly intensifies. Based on the conditions of the day with strong inflow winds, I cannot rule out tornadic winds causing the damage. The sheared off nature of the trees indicates sudden wind blasting the area. Was it from inflow jets and RFD winds or downbursts or both. Inclonclusive either way.

However, picking out some of the tornado damage in Australia is not always a clear-cut decision.

Thanks for posting!

Regards,

Jimmy Deguara

Michael Thomas:
Hi Jimmy,

Thanks for your comments. Unfortunately I have never inspected damage from a confirmed tornado therefore it is difficult for me know what to expect. The things that may hint towards a tornado is that several large trees or branches appear to have been brought down in different directions (maybe up to 90 degrees difference). Also, the nature of the damage is very random. As can be seen in the first image, one section of forest was totally destroyed (every tree snapped) then nearby trees showed little to no damage. This may be simply due to the topography. Honestly though, I know so little about what to expect that I can't make any definitive statements.

The radar image below I find interesting-


The southern storm is well and truely in the process of merging with the northern storm. If you look closely though, there may well be a hook on the southern cell. Seems to really be embedded in rain if that's the case. Unfortunately the resolution of the radar is quite poor and radar images were only recorded every 10 minutes. When it comes to tornadic events, 10 minutes is a long time! I am still leaning more towards this being non-tornadic damage, still worth considering though.

Michael Thomas:
Does anyone know when the images for google maps were taken? I have found what appears to be damage from the Berry storm in Google maps. Very localised but seems to fit with the photos taken above. However, I also looked for Coonabarabran tornado track and could not see damage (edit: actually having another look, I might of missed it before. Still not as clear as I was expecting). Obviously the Coonabarabran tornado was quite destructive so should be visible.

Michael Thomas:
I looked up the location of the damage west of Berry on google maps and it does appear that damage can be seen on the satellite image. It would appear that this damage fits very well with the photos above. I am assuming these satellite images were taken some time after the 20th of January 2005, how long I do not know (if they were taken before then I am just making a fool of myself :)). I have attached an annotated google maps image below-



Here is the direct link to google maps page to zoom in on the relevent areas-
Kangaroo Valley Rd to Kangaroo Valley Rd - Google Maps

This seems to indicate a damage path of up to ~1.5 km long and possibly up to ~200 m wide. This may add further support that this was actually a tornado. If this is the case, it would most certainly be on the lower end of the scale.

Michael

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