Storm Australian Severe Weather Forum

Severe Weather Discussion => Tropical Cyclones, Typhoons and Hurricanes Worldwide => Topic started by: Mike on 13 December 2008, 05:43:38 AM

Title: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: Mike on 13 December 2008, 05:43:38 AM
Looks like I've finally got myself a landspout from a thunderstorm.  Had it confirmed by a seasoned chaser overseas and Michael here also reckons it's a goer.  Two photos for comparison, original and one contrasted to highlight the funnel.  The storm was late afternoon on 29 November 2008. It was a vicious lightning active bugger with heavy precip and obviously with vorticity.

---> Darwin radar loop (http://australiasevereweather.com/storm_news/2008/radar/20081129/berrimah128a.htm)
Title: RE: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: Shaun Galman on 13 December 2008, 09:24:42 AM
Nice capture Mike.

Looked convincing enough to me when I saw the original post a few days back!

Your definitely one up on me lol, not enough water out in these parts to create a spout ;)

Take it easy,
Shauno
Title: RE: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: David C on 13 December 2008, 09:30:47 AM
Nice capture Mike.

Looked convincing enough to me when I saw the original post a few days back!

Your definitely one up on me lol, not enough water out in these parts to create a spout ;)

Take it easy,
Shauno

Nice pic Mike - looks convincing, but not really the location (ie downdraft) where you would expect to see a waterspout - was it in the precip, or is that just how it appears in the photo?
Title: RE: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: Mike on 13 December 2008, 09:54:45 AM
Hard to say where it was located either in or out of it - the precip was pretty intense and the wind was moderate.  Whether this thing was behind the precip curtain and appears inside it given my location then who knows.  Certainly generated a lot of interest up here though!  I think I have some more images without lightning - will have to hunt them unless I've deleted them from the card....
Title: RE: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: australiasevereweather on 13 December 2008, 10:05:57 AM
David and Mike,

I am confused - is this a landspout or waterspout? Looks convincing to me David.

Regards,

Jimmy Deguara
Title: RE: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: Mike on 13 December 2008, 01:59:37 PM
I think it's a land spout, I did a recon drive the other day and there's no dams in behind this plantation that I could visibly see from the road - although there might be .... George Kourounis viewed the images also so that was confirmation enough for me, he told me the structure of it from the cloud base definitely displayed funnel characteristics.  Thanks Jimmy also, your valuable interpretation is invaluable to me.
Title: RE: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: australiasevereweather on 13 December 2008, 02:34:04 PM
I have to say Mike, that's fantastic! When did you exactly notice you had this?

Jimmy Deguara
Title: RE: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: Mike on 14 December 2008, 04:54:53 AM
Not until the next morning when downloading all the chase images.  I got about 3 photos of CGs from the same spot and probably 8 more without, although I deleted the photos from the camera, they still would be 'on file' on the chip as I have not formatted the camera since.  I'll be having a look at those once I figure how to 'get' those files and see if the funnel shows itself.  I would never have looked for that to be honest considering I've never seen or heard of anyone capturing a spout inland - plenty over the harbour of late - and I do look more closely now at storm bases!

I've given the photos and details to BoM here for their consideration.  They compile a detailed spreadsheet at the end of the wet and post it to the spotters network up here of what storms we had, their type, any unusual events, winds etc, etc so it might be useful for them - one would think!
Title: RE: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: David C on 16 December 2008, 05:30:06 AM
David and Mike,

I am confused - is this a landspout or waterspout? Looks convincing to me David.

Regards,

Jimmy Deguara

Jimmy, have you ever seen a landspout, or waterspout for that matter, develop in a region that close to cool downdraft air? Looks for sure to be a tornado of some sort, but it would be interesting to know a little more about the storm/pre-storm conditions at the time. It does not look like a landspout-type tornado in appearance. 
Title: RE: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: Mike on 16 December 2008, 06:01:11 AM
Hi David, I'll dig up some obs re sounding and stuff and anything else if it assists.
Title: RE: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: David C on 16 December 2008, 07:49:04 AM
Hi David, I'll dig up some obs re sounding and stuff and anything else if it assists.

That would be good Mike. That's a nice spout in the other thread too and has the classic waterspout appearance. Top stuff!
Title: RE: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: Jimmy Deguara on 17 December 2008, 04:30:43 AM
Hi David,

My error - I meant to indicate that it was definitely some sort of tornado. Because I saw spout, I had to act on the terminology at hand. So tornado is what it is -w hat dynamics are in place is another matter and it would be interesting whether doppler covers this region.

Regards,

Jimmy Deguara
Title: RE: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: Mike on 17 December 2008, 06:34:05 AM
We have Doppler here which covered that area but to get an archived link might be difficult especially showing Doppler winds.  I'll see if a couple of guys at BOM can get me the run.  Can't even get a satpic loop either - man, this is frustrating and I really should have gotten all this stuff the next day i shot it.

I'll dig deep.

Sounding here but you can add a couple of degrees for temp - more like 33c.
Title: RE: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: cloudfairy on 17 December 2008, 07:01:02 AM
Here you go.... the sat pics.....I did that at home, so I'll check if I can cut out the area. Cause I know I have these pics in higher resolution.
Doppler, I will ask them, but they are really busy atm, with the low and I should be busy too with my MJO.

(http://www.drakenskepp.de/ext/sat20081129klein.gif)
Title: Re: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: Mike on 17 December 2008, 11:41:05 AM
Thanks for the sat images Renate, much appreciated.  It might be a while till I get some decent obs from BoM - as Renate mentioned they're flat out with the monsoon and that pesky low, but I'll keep this thread informed as I get stats.
Title: Re: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: cloudfairy on 17 December 2008, 01:49:28 PM
(http://www.drakenskepp.de/ext/ausschnittTS29112008.gif)

thats the rural area.....don't know if it helps
it's from 05:30Z to 18:30Z with 17:30Z missing.
Title: Re: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: Jimmy Deguara on 18 December 2008, 01:30:07 AM
Satellite imagery although nice to see storms in action cannot really indicate much within the storm environment. We really need radar and particularly doppler to see anything in relation to this tornado. I would have thought that the meteorologists on duty would have taken some interest in the event and exchanged with you willingly...

Best of luck Mike,

Regards,

Jimmy Deguara
Title: Re: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: cloudfairy on 18 December 2008, 03:42:15 AM
As soon as they look a bit more relaxed I will ask them for the doppler
Title: Re: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: Mike on 18 December 2008, 05:22:45 AM
Indeed Jimmy.  I've emailed my contact and he's been on duty but they tend to drop everything when the monsoon ramps up and Renate is my only saving grace simply because she's in the office studying and is helping to gather info.  I've asked for the Doppler loop also.  The info will come in time...:)  Satpics show decent storms but a lot of anvil wash also so not much to go on there, so i agree with that.
Title: Re: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: Mike on 31 December 2008, 08:11:09 AM
Drove out to the location today to try and locate a damage path or anything from this funnel.  There were some downed trees but I doubt these were from this funnel (if it indeed caused any damage) and more likely from strong storms of late.  There was a track of downed trees along side the road but they looked too old to be the ones if they had been knocked over by it.

I've still got the feelers out to the locals in the area to get back to me if anyone mentions to them they have damage from that storm.  BoM here are keen to find out a little more on it but don't have the time at the moment to go out surveying of sorts, so it's left to me.  They have emailed thanking me for the images and report but indicated they are still flat out with handling the monsoon and the lows around us, but invited me to come and chat to them.

From the area this funnel was seen it's in heavy bush and may be on someone's property.  Most homes in that area have acreage of between 2-7 acres, so access is difficult and they don't tend to clear much bushland.  The main area of interest is between the Arnhem Highway and Power Road, there is no access to the bushland from what I saw, but hopefully someone will come forward with any additional info for me.

I'm visiting BoM next week so I'll be asking to see any archived Doppler etc from the day and asking questions so maybe that might clear things up atmospherically wise for us.
Title: Re: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: Mike on 17 January 2009, 08:25:13 AM
BoM Met officer's assessment 16/1/09

I visited the bureau this morning and Michael Foley was kind enough to locate some Doppler and also utilize 3D cross section images from the storm that produced this funnel.  Renate sat in also (cloudfairy) and gave some worthwhile input and questions as we searched - onya!

The archived stills from the satellite (which had this special camera mounted on it for the 3D graphics to view) showed this particular storm to have a very strong updraft core and indeed did sit fore of a low level boundary (Correct, Nick!).  There was a sea breeze pushing inland from NE to SW towards a collective group of cells which built during the loops and these were the storms we also saw either side of the highway close to us forming and anviling out.

Doppler showed some winds turning towards those shown away from radar.  Although the wind profiles indicated not much in the way of vorticity he did not rule out the possibility of a short lived funnel and due to the 10 minute captures this particular satellite takes it may have missed it.  The funnel I saw probably lived for about 2-3 minutes and he said that could be the root problem of it not showing up on Doppler.

 There was evidence of a - ..... damn forgot the terminology .....something along the lines including the word 'hook' - but I knew what he was talking about when he mentioned it.  We looped several times and the one closest to that particular ET showed good strong shear in the middle of the core but no further which we agreed this may be why the funnel's length was shortish compared to the storm.  The loops don't show the cell at its strongest stage - the images kind of skipped that vital frame on viewing it and Doppler was much the same.  The missing link was just not captured for that 5 minutes needed.

Looking at their particular radar (not remotely similar to the public viewed one online) you could clearly see the stronger areas of the storm interior and there were red spikes which indicated strong updraft/downdrafts in one region of it.

Nothing more we can do in terms of data - everything was pretty ideal for it, we just don't have the capture from the satellite.  Unless I find a damage path or one resembling a track then that's it in a nutshell.  He did conclude that it might have been a gustnado given what he interpreted but did not state it categorically as being final.

They've kept the photo and things for the next Storm Spotters report anyway and if i find a damage path of any kind out there then I should report it straight away to him - might have to go with that GPS option I posted earlier.  Hope this was of use everyone, sure was to me.

Title: Re: Tornado Humpty Doo, Northern Territory: 29 Nov 2008
Post by: cloudfairy on 17 January 2009, 09:11:06 AM

 There was evidence of a - ..... damn forgot the terminology .....something along the lines including the word 'hook' - but I knew what he was talking about when he mentioned it.  We looped several times and the one closest to that particular ET showed good strong shear in the middle of the core but no further which we agreed this may be why the funnel's length was shortish compared to the storm.  The loops don't show the cell at its strongest stage - the images kind of skipped that vital frame on viewing it and Doppler was much the same.  The missing link was just not captured for that 5 minutes needed.


Hook echo, it is when the echo looks like a bow. There is a bit of vorticity on its edges.