Hello

Archive of General Weather
Forum rules
These topics are a read-only archive and may be subject to out-of-date information.

For today's weather discussion head to: New Zealand Weather & Climate
Locked
NZ Thunderstorm Soc
Posts: 18488
Joined: Wed 12/03/2003 22:08
Location: Raukapuka Geraldine
Has thanked: 1769 times
Been thanked: 1412 times

Hello

Unread post by NZ Thunderstorm Soc »

Hi from the NZ Thunderstorm Soc, the NZ Boring Weather Soc,the Anticyclonic Gloom club, the I hate Kay Gregory Club, whatever...
Good to have a NZ weather forum on-line again, (and from Christchurch)lets hope (...removed...) that you Graham keep things in line that any discussion on this forum is related to weather discussion only.
No interesting weather to note, except for some uninteresting weather we had today, and yesterday and the week previous. Looks like more to come :( :( :(


JohnGaul
NZBWS

Edited by moderator 18/3/2003
Thunder
Posts: 2068
Joined: Wed 12/03/2003 19:47
Location: Mt Somers
Has thanked: 19 times
Been thanked: 41 times

Hi John

Unread post by Thunder »

Yes nothing interesting happining at all. Well I guess thats all I have to say at present, where is Jim Hickey? I've never really had a grudge against any of the weather presenters but if anyone, yes I would say Kay as well.

Aaron Wilkinson :(
Skywatcher
Posts: 1249
Joined: Fri 21/02/2003 13:11
Location: Templeton, Christchurch
Has thanked: 0
Been thanked: 49 times

Unread post by Skywatcher »

Agreed, it's not like we're even getting any rain !

The only interesting event from last week was that the sferics counter I made and installed after the last ChCh storm finally registered some activity .... from the West Coast !!!

This shows 22:00 on the 2nd to 19:00 on the 3rd:

Image

At the moment the count represents the number of 50ms intervals that the input remains on for during a minute - prior to this I recorded no more than 10 per day !

I plan to upload live data to the website every 15 minutes when I get the time ;)

Steven
NZ Thunderstorm Soc
Posts: 18488
Joined: Wed 12/03/2003 22:08
Location: Raukapuka Geraldine
Has thanked: 1769 times
Been thanked: 1412 times

Unread post by NZ Thunderstorm Soc »

Great stuff and also your Web site, Graham
Fantastic to a have sfreric recorder from somewhere in Christchurch
...and Aaron, I see you have found this forum
Some lovely Cu development around the Port Hills today with the NE against the southerly. Barometer, even tho' solid in movement, down to below 1010hPa, first time for a while. May get a southerly change tommorow afternoon, first time for a while !!!


JohnGaul
NZTS
User avatar
NZstorm
Posts: 11333
Joined: Mon 10/03/2003 19:38
Location: Grey Lynn, Auckland
Has thanked: 342 times
Been thanked: 361 times

Unread post by NZstorm »

Steven
You will need to calibrate the lightning counter to detect strikes within
the immediate area only (say within 10km). That way it will serve to
represent the local area.
Cheers
Matthew Pearce
Posts: 8
Joined: Thu 13/03/2003 17:15
Location: Sydney, Australia
Has thanked: 0
Been thanked: 0

Unread post by Matthew Pearce »

Hi all

Good to see this forum up and running! I used to visit the old one occasionally but got very frustrated at the way it was set out. This is very slick and much easier to get around...I will be a regular visitor!

I was born in NZ(Auckland), grew up there(AKL and Wellington), then left. I have been in Australia for 11 years now so now call myself an Aussie through and through(sorry guys).

However, I still visit NZ every couple of years to see relatives and still hold a strong interest in the NZ weather. eg the only tornado I have seen to date has been in NZ(at National Park a couple of years ago).

So, once again, good to see this site going and...I'll be back :)

Matt
CbFan
Posts: 182
Joined: Mon 10/03/2003 20:54
Location: Far North, NZ
Has thanked: 13 times
Been thanked: 46 times

Unread post by CbFan »

Steven,
That sfx counter - home built?

Would be interested to hear about your setup. Do you use any isolation from your PC (Optical, diode or ???)

(I have a basic system but unfortunately it is very expensive to run: I have a 120m copper mast connected directly to my PC power supply, I simply count the number of times I have to buy a new computer each month to work out the lightning count :)
Skywatcher
Posts: 1249
Joined: Fri 21/02/2003 13:11
Location: Templeton, Christchurch
Has thanked: 0
Been thanked: 49 times

Unread post by Skywatcher »

The lightning counter is much more sensitive than I expected - I wasn't even sure it was really working until last week. The simplest way of cutting its range is to lower it (3m agl now) and move it to an eastern wall to use the house as a shield to the west - or even put it inside !

Of course, I really need a local storm as a reference ......

It uses a very simple, untuned design from:

http://homepage.mac.com/tbitson/weather/owlm/

but I get the opto-isolator to pull down the input of a basic DSE micro-controller which just sends a "p" to the serial port of the PC for each 50ms it stays low. Of course, the opto-isolator is only rated at 5kV so it's minimal protection and mostly to stop false triggering - hopefully the earth connection would take most of the energy if it's not a direct hit !

I'm going to update it the code to send the duration of each continuous pulse so that might give more information on proximity.

That's an expensive 1-bit counter with a slow reset time you have !!!

I have UPS's on my PCs but that's because there are enough outages here (cars, trees bringing down lines) to be a nuisance - they have "surge protection" but I'm not sure that would be enough for your situation.

Steven
Thunder
Posts: 2068
Joined: Wed 12/03/2003 19:47
Location: Mt Somers
Has thanked: 19 times
Been thanked: 41 times

Possible Cb for the 12th in Chch

Unread post by Thunder »

Hello

John, on the 12th you mention nice Cu, I'm thinking they could of also gone to a small Cb as shown by this satellite pic

http://satellite.landcareresearch.co.nz ... d12033.txt

Is that Cb sort of looking stuff, could be? notice the wispery sort of tops suggesting the top of a Cb.

Oh and thanks Steven for providing this forum, it's really cool!

Aaron Wilkinson
Manukau heads obs
Posts: 12305
Joined: Mon 10/03/2003 16:30
Location: West Coast Road, Manukau Peninsula, North Island
Has thanked: 0
Been thanked: 0
Contact:

Unread post by Manukau heads obs »

thats the same design i have in use here , for counting lightning strikes...using a dallas 1 wire setup....and my software....which can be added to any weather station setup....
50 miles radius it supposed to have.....a good earth is the key :)
(http://ps.gen.nz/~windy/lighteninggraph.gif)

you can purchase them as a kit or pre made....i have one here that I am going to install at the Brynderwyn weather site next time i am up that way (south of whangerei)
pity we cant have access to the met service lightning maps
the idea of the pusle length has been branded about on the 1 wire discussion list....let me know if it works!
Image
Brian Hamilton, weather enthusiast. My weather dataEmail: [email protected]
Skywatcher
Posts: 1249
Joined: Fri 21/02/2003 13:11
Location: Templeton, Christchurch
Has thanked: 0
Been thanked: 49 times

Unread post by Skywatcher »

Here's an alternative which is tuned and has a sensitivity adjustment - it can also be standalone and even portable.

http://www.techlib.com/electronics/lightning.html

It might be interesting to see how it compares with the simple design.

Steven
tich
Posts: 3467
Joined: Sat 15/03/2003 18:32
Location: Christchurch (St Albans)/Akaroa
Has thanked: 21 times
Been thanked: 91 times

Unread post by tich »

Hello

Good to see a proper NZ weather forum starting up again. Like John has said, it's been pretty quiet down here lately, and dry as well - even the forecast drizzle hasn't yet eventuated. However I did notice a heavy surf at New Brighton on the NIWA webcam, courtesy of the departing low leaving the Chathams. Pity the Napier beach cam hasn't been updated - there must've been some massive swells there if the forecast was right.

Ben Tichborne
NZ Thunderstorm Soc
Posts: 18488
Joined: Wed 12/03/2003 22:08
Location: Raukapuka Geraldine
Has thanked: 1769 times
Been thanked: 1412 times

Re: Possible Cb for the 12th in Chch

Unread post by NZ Thunderstorm Soc »

[quote="Aaron J Wilkinson"]Hello

John, on the 12th you mention nice Cu, I'm thinking they could of also gone to a small Cb as shown by this satellite pic

http://satellite.landcareresearch.co.nz ... d12033.txt

Is that Cb sort of looking stuff, could be? notice the wispery sort of tops suggesting the top of a Cb.

Oh and thanks Steven for providing this forum, it's really cool!

Aaron Wilkinson[/quote)

Yes, the cloud did look interesting in a period of non-eventful weather.
It may of been a bit cooler in the upper air, but I didn't see any glaciation.
But owing to the fact we are in a settled, mainly anticyclonic weather period, I didn't expect anything. We had our chance over the spring and early summer when low pressure systems passed over or near to the country but now weather patterns have changed. Cyclones/low pressure systems to the north of NZ don't help much either.


JohnGaul
NZTS
Thunder
Posts: 2068
Joined: Wed 12/03/2003 19:47
Location: Mt Somers
Has thanked: 19 times
Been thanked: 41 times

I'm always hopefull

Unread post by Thunder »

Yes it might of been a small Cb or might not have but then...

looks like some nice cumulus congestions etc popping up over the N Is today from the NOAA Sat pic (18th).

Can't wait until I hear that sound of hard rain hitting the roof and knowing I'm inside a warm cosey (spelling?) house, we haven't really had any good sort of stuff for a while now here in Cantab.

Aaron Wilkinson
Locked