I noticed on MetService's Thunderstorm Warning for tomorrow, that they are expecting ...and I quote
"Garden Variety Thunderstorms"
Do they have gardens down there in Fiordland?
Then, the trough following in behind, brings a moderate risk of garden variety thunderstormsto Fiordland,Buller and northwest Nelson. These may be accompanied by potential wind gusts of 90-110km/hr.
Last edited by NZ Thunderstorm Soc on Sun 24/06/2012 15:30, edited 3 times in total.
From just before 2pm the real heavy stuff started & it was relentless until 3.. by then the damage had been done & the water was still coming down from the escarpment so unfortunately all you could do was watch it rise, do it's damage and then bugger off just as quick. Brian is pretty much on the mark with it being on the back edge of the front.. after that it was just sporadic quick heavy showers and 2 huge claps of thunder.
Just checking the latest gfs, that shortwave coming into the west of the NI tomorrow morning will have a bit of thunder activity with it. While there isn't much instability, the 500mb temps are -25C. More aimed at Taranaki though.
Appreciate the reports Dale and thanks for the topographical explanation. Like the 'dart through a straw' analogy btw - thought it must've been something along those lines. And yes, I gathered that was a best rainfall/hour guestimate based on a manual, but reliable gauge.
Your intensity time-frames also sound about right going by NIWA's latest Greymouth Aero data. It recorded 36.6mm in the 24 hrs to 9am this morn, 25mm of which fell between 10am and 3pm yesterday, including 8mm in the highest hour to 2pm.
I would never have believed it if I was still up in Auckland.. you really have to be here & see it for your own eyes, such a huge contrast in rainfall on a regular basis (vice versa also) in such a short distance (<10 miles).. have also heard it dumped rain all the way from here, through Taylorville/Stillwater and onto Dobson.. which sends it right through the Omoto Valley & bypasses Greymouth altogether. A very interesting weekend to say the least. Very chilly out there tonight, can feel that cold blast coming already!
Yup heard thunder at about 7.35 just as i was about to leave for work. On the way to work i had a flash of lightning right on top of me. Now its very dark at work with heavy rain.
Looking at the gfs yesterday my thoughts were that you couldn't get an upper level system like that crossing with out some thunder!
We get the same deal again tomorrow morning.
Dale Small wrote:I would never have believed it if I was still up in Auckland.. you really have to be here & see it for your own eyes, such a huge contrast in rainfall on a regular basis (vice versa also) in such a short distance (<10 miles).. have also heard it dumped rain all the way from here, through Taylorville/Stillwater and onto Dobson.. which sends it right through the Omoto Valley & bypasses Greymouth altogether. A very interesting weekend to say the least. Very chilly out there tonight, can feel that cold blast coming already!
The question is begged ... what is the average annual rainfall in the vulnerable areas you're referring to? - even at Greymouth it is over 2400mm. Of course there may be compensating scenarios where these areas miss out ...
- thought it must've been something along those lines. And yes, I gathered that was a best rainfall/hour guestimate based on a manual, but reliable gauge. 
