Troughs and Possible Storms- Sep 25-30

Tornado Tim · Unread post by **Tornado Tim** » Fri 23/09/2016 10:24

Looking at several models, it seems we are entering into an extended period of rather interesting weather next week with a trough forecast to be stuck in place over the North Island for a few days.

If this forecast remains, we are most probably going to see the first spring/summertime convection setup. With unduly cold temps forecasted next week, could well be very interesting.

Richard · Unread post by **Richard** » Fri 23/09/2016 21:25

Looking even possibly unstable for inland areas of the SI Wednesday too.

NZstorm · Unread post by **NZstorm** » Sat 24/09/2016 07:51

Great to see a system there for a week providing thunder chances.

I may go for a drive north tomorrow. Upper levels are looking good, comes down to surface parameters.

spwill · Unread post by **spwill** » Sat 24/09/2016 08:37

At this stage Monday afternoon over Northland might be interesting, frontal Junk has moved out the way with some very moist air in sunshine.

NZstorm · Unread post by **NZstorm** » Sat 24/09/2016 10:54

spwill wrote:At this stage Monday afternoon over Northland might be interesting, frontal Junk has moved out the way with some very moist air in sunshine.

I think this will happen Sunday afternoon. 12Z Ukmet was showing drier air aloft over Northland tomorrow pm.

spwill · Unread post by **spwill** » Sat 24/09/2016 17:53

See how it looks in the morning, GFS showing warm humid air mass over northern NZ tomorrow.
dewpoint forcaste pm

NZstorm · Unread post by **NZstorm** » Sun 25/09/2016 10:03

Thunderstorm chances over Northland today look highly conditional on surface heating.
18C will produce about 250 CAPE whereas 20C will yield about 500+ CAPE.

spwill · Unread post by **spwill** » Sun 25/09/2016 11:47

Northland catching some sunshine now, Whangarei on 20C.

jamie · Unread post by **jamie** » Sun 25/09/2016 13:50

Looks like a line between kaipara harbour and whangarei

Manukau heads obs · Sun 25/09/2016 16:18

looks like a low center passing right over us here...going by rain radar
50mm or so here

Richard · Unread post by **Richard** » Sun 25/09/2016 18:11

Been getting some good steady rain here most of the afternoon

Manukau heads obs · Sun 25/09/2016 18:30

we are stuck in a rain band that keeps on forming right over the top of us..
60mm here now total

NZstorm · Unread post by **NZstorm** » Sun 25/09/2016 19:17

Went for a drive to Kaiwaka this afternoon and observed tropical style downpours but non thundery.

I see the Pinnacles on the EW site has had over 200mm last 24hrs.

Manukau heads obs · Sun 25/09/2016 19:18

67mm or so here now..it just wont stop..the last remaining rand bands are stuck in place...

Manukau heads obs · Sun 25/09/2016 20:22

looks like you should get more rain at times Richard over the next few days too

NZstorm · Unread post by **NZstorm** » Mon 26/09/2016 06:52

Pinnacles showing 380mm for event now. The Coromandel is certainly a wet place!

Richard · Unread post by **Richard** » Mon 26/09/2016 06:53

Manukau heads obs wrote:looks like you should get more rain at times Richard over the next few days too

Be so good if this light rain keeps up, was looking to kick the irrigation into gear anyday

Nev · Unread post by **Nev** » Mon 26/09/2016 07:00

NZstorm wrote:Pinnacles showing 380mm for event now. The Coromandel is certainly a wet place!

Yes, 380mm for the 48 hrs to 6am this morn, with 300mm of that in the last 24 hrs...

Tornado Tim · Unread post by **Tornado Tim** » Mon 26/09/2016 21:11

West Waikato poses the risk of storm tomorrow with the SFC NE and Easterly and broad trough of low pressure and cold upper level temps should see something pop up come mid-late afternoon.
No shear and easterly steer is somewhat weak, convection will be pulsy with potential slow storm movements.

David · Unread post by **David** » Tue 27/09/2016 10:37

NZstorm wrote:Pinnacles showing 380mm for event now. The Coromandel is certainly a wet place!

Approximately 700mm there in the past 7 days!

Richard · Unread post by **Richard** » Tue 27/09/2016 11:00

wow thats a lot , dont know if we've had that in the last two years

spwill · Unread post by **spwill** » Tue 27/09/2016 12:32

A sunny morning here, currently 18C, dewpoint 15C. Not looking like we will get convergence around here today but southern parts of the Auckland region may do.

jamie · Unread post by **jamie** » Tue 27/09/2016 15:29

The sky is quickly changing to my SW. The radar is showing development too.

spwill · Unread post by **spwill** » Tue 27/09/2016 16:36

Parts of South Auckland catching an afternoon shower.
Been a nice day here.

NZstorm · Unread post by **NZstorm** » Tue 27/09/2016 18:42

Glaciated cb to south but no lightning recorded.

Grey Lynn 20C today.

NZ Weather Forum