Frontal System - 14th-16th September

[Tornado Tim]

Quite a beefy multi cell line going by Radar

[GraemeWi]

Lightning and thunder in Henderson. Looking good! Seen several strikes so far.

[GraemeWi]

IMG_0945.JPG

Edit - added picture


Hail now

[Manukau heads obs]

cool , hope it comes down this way ...timing it right for dark...
we have had some good build ups already here in front of it

[NZstorm]

Just got back from a quick drive west, saw some nice CG's and thunder. Storm has some structure to it.

[littleheaven]

Just snapped a nice shelf cloud on my way to my parents house. Shame I have no way of uploading it right now!

[Cook]

A bit of hail...

aldSept16
At 05:45

[GraemeWi]

Here is another image taken a few seconds after my first. Looking north from Henderson just before the rain and hail started. I observed a couple of strikes and good close thunder from it.

IMG_0946-001.JPG

[spwill]

Nice storm over West Auckland, watched the show from up on Mt Roskill , observed some nice lightning strikes over NW Auckland and across the Waitaks,

[littleheaven]

Managed to borrow a camera cable from Dad. Here's the shot, taken on a little Sony point & shoot I had in my handbag. Sadly does not do the cloud justice, it looked amazing with the setting sun behind it. Heard one clap of thunder before I saw this, and after I got to my parents' house there was some low, swirling stuff going almost over the top of us. I could see some good CB's off the East Coast as well.

[Tornado Tim]

Looks like a possible wall cloud was reported on the storm (with photo):
http://www.weatherwatch.co.nz/content/a ... ai-airbase

When clouds start to fan out at the base (and look crisp like in the photo) it strongly suggests air is being drawn in as opposed to a outflow.
If there was a video, id like to see to see to confirm my suspicion to see the wind flows.

Fantastic Photo!

[spwill]

That is a great photo, looks like a wall cloud there.

A view of storm clouds from Mt Roskill looking NW

[David]

Thunder here

[jamie]

A bit of hail...

aldSept16
At 05:45

wow how did you manage to make a higher resolution image?
EDIT: oh wait looking at that you have some special program that is tracking the cell a bit like GRL4 in USA. What do you have and how can i get my hands on it?

could see lightning to my NW before

Interesting reports of such structure such as wall clouds

[Tornado Tim]

wow how did you manage to make a higher resolution image?
EDIT: oh wait looking at that you have some special program that is tracking the cell a bit like GRL4 in USA. What do you have and how can i get my hands on it?

I would think he's got access to another radar subset from Metconnect (i bet it would be expensive! or he's part of M/S team). Metservice putting out data out into 3rd party program to style is very unlikely.
Looks like its smoothed too, Smoothed Radar images may look more nicer but they are less accurate to a degree esp if they are raster based.

The Radar software that Metservice runs is exactly the same as what NWS use such as storm attributes, hail size etc.

[jamie]

Looks like a possible wall cloud was reported on the storm (with photo):
http://www.weatherwatch.co.nz/content/a ... ai-airbase

When clouds start to fan out at the base (and look crisp like in the photo) it strongly suggests air is being drawn in as opposed to a outflow.
If there was a video, id like to see to see to confirm my suspicion to see the wind flows.

Fantastic Photo!

looks like a wall cloud to me!

[NZstorm]

Fantastic photos and yes, a wall cloud photo in that link.

The shear numbers looks good today with 75kt NW at 500mb!

[Tornado Tim]

The shear numbers looks good today with 75kt NW at 500mb!

Yes some good upper level speed shear today.

Noon Sounding attached:

[spwill]

Call that our first warm season storm with the afternoon heating being a factor, up to 17C, dewpoint 13C.

[NZ Thunderstorm Soc]

Reasonable set up for thunderstorms in Canterbury tomorrow with the cold southerly and good timing with it coming in later on, onshore coastal winds prior also.
Moderate risk on MS, ive been keeping an eye on that front the last few days its hard to say its a high risk being only 16 days into spring and sea temperatures are not that warm yet either.

Not too sure on this one Jason
Thinking if it is squally, it will be a gust front moving over with about 3 spits of drizzle and a strong SW change, then clearing up later in the evening with a frosty night developing.
There could be thunderstorm activity prior to the change, ie. "Thunderstorm Corner" !

[Manukau heads obs]

passed just to my east
saw some good lightning

and yes good structure

[Thunder]

Nice storm up there today! And yeah a classic looking wall cloud, brilliant!

Am looking forward to something here tomorrow, not totally sure of how things will develop but perhaps starting off near Rakaia around 3 or 4pm as usual and eventually the system moving onto the Amuri Plains about 5 or 6pm. Ruff timings but let's see. Guess we'll see a new thread tomorrow should things set off.