NZ Weather Forum

Pic looking south from central Auckland about 2.30pm.

A private weather station in Ramarama South Auckland recorded 61mm between 1.45pm and 3pm.

Nice photo NZStorm. Also like your mother's video of the storms over the BOP, Tornado Tim.

I chased South Auckland to North Waikato this afternoon, some very nice storms in that area early to mid afternoon.
Some photos from around Bombay

Great photos Spwill.

Cheers Gregg.

Joined two photos to show a gust front forming on a storm in North Waikato

Well done everyone very photogenic storms

A couple more photos, storm forming near Pukekohe, storm over the Manakau harbour

I've got some late convergence very close to me. Still growing according to radar. Might catch a few more mm. We only got 4mm here today. Just a few km away had flash flooding.

CB over West Auckland. This cloud developed into a nice thunderstorm but stayed in the Waitakeri ranges.

Some photos from today. Near Ohaupo.

Great Photos, some storms had good height to them by the looks. Decided not to chase today ,hope you guys out there had a good one ! See what later next week brings.

Richard wrote:Well done everyone very photogenic storms

Agree!

Very jealous of you guys up there. Interesting as weather maps don't look like an event like that would happen?
What was the trigger?
The sun came out here this afternoon. Nice to see it from all the boring claggy weather we have had down here over the past week, although it has been useful rain -wise.

Mint photos all round

Yea, So I headed from Hamilton to Mercer, Storm Started Developing along a line to the North, then went up the Bombays when it hit, quickly turned "Severe" with the huge volume of water that was being dropped. Traffic started to get rather chaotic with quite a large amount of people pulling over or just slowing down to 10 to 20km/hr in order to drive safely.
Police were out with Lights flashing warning people about conditions.
Went further North under the storm the entire time (While Severe Warned), then headed West to Waiuku, the storm moved over the Harbour but a second came behind it. Meet up with Jamie watching the storms develop and then fizzle.
Shortly after Jamie called it quits and went back to Hamilton, I left back to go to the Tron, and got treated to more storms going back!
Core punched one as I got back to Tirau and there was a large amount of surface flooding, so much that you had move on to the oncomming lane. Then caught another Storm in Rototuna Hamilton, then took some pics of storm that Jamie got, that had quite a bit of Hail come out of it.

Main comment about these storms, is the vast amount of Rain falling, was ridiculous, it made driving really hazardous if you core punched. The amount of Thunder on each storm was notable too.

NZ Thunderstorm Soc wrote: Interesting as weather maps don't look like an event like that would happen?
What was the trigger?

An upper level trough was crossing the area yesterday.

Grey Lynn tracker picked up 4500strikes, most of it with the South Auckland storm. But there have been no reports of any damage.

There would have been many more strikes as the small IC discharges often dont get picked up.The Whakatane storm the prev evening may have had 5000 discharges over 3 hrs alone, a lot more than would have been picked up.

NZstorm wrote:

NZ Thunderstorm Soc wrote: Interesting as weather maps don't look like an event like that would happen?
What was the trigger?

An upper level trough was crossing the area yesterday.
.

The air mass across northern NZ has been more moist than usual, a dewpoint around 20C for aleast the last week. I think Cyclone Victor helped reinforce moisture levels in our region. I recall a cyclone some years back giving us a period of thunderstorms in the moist air it left behind.

treetop wrote:There would have been many more strikes as the small IC discharges often dont get picked up.The Whakatane storm the prev evening may have had 5000 discharges over 3 hrs alone, a lot more than would have been picked up.

Both days had some wind shear which contributes greatly to the lightning rate.

Thats true , also its rare to see frequent dicharges like that at night so peak heating/convective times ie 12-7 pm must play a part as well.Not sure about other parts of the country but this is common in BOP afternoon storms.

treetop wrote:Thats true , also its rare to see frequent dicharges like that at night so peak heating/convective times ie 12-7 pm must play a part as well.Not sure about other parts of the country but this is common in BOP afternoon storms.

Re BOP storms Sat evening, the heating would have been a big part of the initial trigger but I would say very good wind convergence lift would be the reason why the storms kept going into the evening as they crossed the coast.

Nice photos! ! Some nice towers there spwill! Nothing really on the horizon down here this week! In fact since the December storm day there's been nothing at all