Topic: Severe storm damage opinions

[Mike]

I've attatched some images from a storm set that came through from 12 Jan through Manton Dam region in rural Darwin.  Is a localised event but downed trees suggest microburst activity.  Could experienced members comment on the images and give their opinions as to what it may have been?

From radar loops that night two storms stood out. One entrained cell that went through Manton Dam region and another some hours later which was a tight BER line that i think is the culprit.









note how grass is bent in the same direction even three days post storm.

[Michael Thomas]

Hi Mike,

Thanks for the photos. From what I can see, all the trees are aligned in the same direction so I would have to guess straight lines winds. Most of been quite strong though to do that kind of damage (120 km/hr + ???).

I would like to look further into this storm setup. It really looks quite potent. Here are a few soundings from Darwin-

http://weather.uwyo.edu/cgi-bin/sounding?region=pac&TYPE=GIF%3ASKEWT&YEAR=2011&MONTH=01&FROM=1100&TO=1300&STNM=94120

The 0Z and 12Z on the 11th are particularly interesting. CAPE of 2000-2500 j/kg, low LCL's and very strong shear in the lowest 6 km. In fact, on the 12Z sounding, 800 mbar winds are 50 knots! Not really suprising to see damage with a setup like that. I don't think the possiblity of tornadoes could be ruled out either.

Here is the radar loop -

http://www.theweatherchaser.com/radar-loop/IDR633-darwin-berrimah/2011-01-11-00/2011-01-12-23

Have I got the right storm and date/times Mike? Thanks again for that. Geez! Are there any photos of the these storms?

Michael

[Mike]

Hi MT

We had a low in the Kimberley region which was sending spikes off it and the lines were coming every two to three hours moving across Darwin and the rural regions.  These storms that caused the damage were at night and given the constant low based cloud (with associated continual lightning!) nobody had any photos of those storms...sadly.  Even if it was during the day most chasers here would have stayed in town anyway given the lightning displays which were constant IC flashing, low cloud based streamers and the odd CG.  There were wind recordings from various locations of 100km/h along the coast, the bureau wanted some clarification of this as most of their wind finding detected gusts of 90 or so...the Darwin/Daly region was experiencing some very large sets of storms embedded in the spikes and Doppler certainly concurred that outflowing winds toward the radar were gusting to over 100km/h in some regions.  One line which is shown on the radar loop was severe storm warned for damaging winds...but given the speed at which these storms came through every couple of hours you could probably take our pick as to which one did the damage that night.

I must add that this is the first monsoon I have seen with such low lying cloud cover which continually flashed with lightning...thunder sounded like booming CG's but in fact was low lightning flashing within the cloud base non-stop, but that low pressure cell certainly contributed to the deepening instability to enhance mixing.