Low to cross country early week of 11th-15th Aug'

[NZstorm]

looks like a low will develop in the Tasman early week and cross the South Island Tuesday. Rain should be fairly widespread across the country Tuesday. Unstable WSW flow with blustery showers follows the front and looks like persisting for the week.

Points of interest in the weather, there could be the odd thunderstorm/hail in the west due to cold upper air. Tuesdays front has a thunder risk for northern and western areas. And I wonder whether there could be a warm frontal snow effect for inland South Island Tuesday. Not sure about that one but the warm front does come in hard on the heels of some chilly air over inland South Island.

Later in the week the trough across the country may amplify further according to GFS/ECMRF.

[Manukau heads obs]

Not sure about that one but the warm front does come in hard on the heels of some chilly air over inland South Island

good point....worth noting me thinks!

[Andy]

Yea cold temps this morning in inland areas of the south island, probably close too or the coldest so far this winter. Air temps in Central Otago were colder than –7).

So plenty of cold air in the basins, will help with warm advective (spp)? snow fall possibilities

[NZstorm]

I see Rickys lightning tracker is picking up strikes from the cb's in the mid Tasman already. While this next system has lots of cold upper air there won't be great moisture advection into it so I expect lightning activity to be more of a dribble on the trackers than a blaze like we saw in systems earlier this winter. But we'll see. Tuesdays cold front could be interesting in the north.

[spwill]

A rather wet week ahead for western area's by the looks with a lot of heavy shower clouds likely to develop in the Tasman Sea.
Hopefully a lightning show or two for Ak.

[NZ Thunderstorm Soc]

Later in the week the trough across the country may amplify further according to GFS/ECMRF.

Yes. It does look very much likely that the trough will eleongate and be with us throughout the coming week and into next WE. An early disturbed westerly regime looks likely.
On the downside, it may be quite anticyclonic over the country this spring?

JohnGaul
NZTS

[Manukau heads obs]

yes, picking up those strikes here too, already (being bounced like a short wave radio signal does)
http://www.weather-display.com/windy/gb/nexstorm.png

[Razor]

Hmm metservice now confirming this warm advective snow thnig is happening tonight? Rain developing and snow to 300m. Could be interesting.

[CHCH Weather Chaser]

Yes razor, I reckon tonight and into tomorrow could be quite interesting cause we have barely managed to get out of single figures today and the air is certainly got that winter chill to it, I see there is a weather advisory for heavy snow inland Canterbury and otago. Looking at 7 day maps it shows some interesting stuff Friday to Sunday coming up from the Antarctic

[spwill]

A sparkling day over the Waitemata today, calm before the storm.
Radar shows a line of heavy rain out to our west, there is also some thunderstorm activity on track for Northland.
Mild 12C, dewpoint 10C.

Looking very wintry from this weekend for NZ according to ECMWF.

[NZ Thunderstorm Soc]

Looking very wintry from this weekend for NZ according to ECMWF.

YES. I was going to create a new thread on this one, but there may be some swearing involved
With the current weather patterns, people I know, are getting sick of the weather turning to 'pooze' in the WE, and they come up to me and ask these 'ordinary' questions like "Why does it turn to crap on the Weekend?" and I say "Well, it's the way it is, sorry".
It gets frustrating

JohnGaul
NZTS

[NZ Thunderstorm Soc]

Obviously no "Squally thunderstorms" up north tonight as the forum has been rather quiet up there

JohnGaul
NZTS

[NZstorm]

The lightning over the sea to our west ceased before reaching the coast. I wonder whether the NNE flow coming off Northland undermined the instability?
Looks to be a thunderstorm in the Rotorua area this morning.
The trough line coming through this afternoon could be worth watching.

[Cameo2]

It definitely isnt cold this morning either, and also, yesterday was spectacular and I could smell Spring in the air Exciting stuff

[spwill]

Looks very cold over the SouthIsland this morning given the cloud cover, web cams show light snow fall over parts of inland Canterbury.

Isolated Thunderstorms west of the NI this morn and over the Bay of Plenty.
Overcast here, showers, light winds and 12C, dewpoint, 11C.

[Razor]

3 degrees and cold cold rain falling here in ChCh. Can't feel my hands!

[Nev]

...Overcast here, showers, light winds and 12C, dewpoint, 11C.

More like steady light rain here atm (over 15mm since midnight so far). Yes, overnight-temp remains unchanged at about 12°C. Was a little gusty here earlier; Hauraki Gulf's Channel Island typically bucking the overall trend with 67km/h mean-winds at 9am.

EDIT: Front began clearing 30 mins later and temps slowing rising.

[CHCH Weather Chaser]

The metservice is showing waiouru as the wettest place in the last hour (9am-10am) with 50.4mm. Surely thats a mistake?

[Nev]

Report of a tornado (or microburst?) in Mt Maunganui at about 8.15am this morning ...

'Roof ripped off garage - "all the windows ... started shaking" ' - Bay of Plenty Times
' 'Tornado' damages Mt Maunganui houses' - Radio NZ

[Vertigo]

unstable atmosphere today...

[David]

Just as school got out, some of the most torrential rain I've seen for some time swept in. Worst timing for torrential rain in many years.
Soaked through in a matter of 2 minutes! As usual, the eastern beach rain gauge reported 14mm from the shower and just 6mm at home. Note that most of the 10.4mm it reported from 3.00pm to 3.15pm fell in the 5mins after 3.10pm. Despite it being 2-3 times less significant here I will still note it in my records

23mm now today (30mm at eastern beach)

[Manukau heads obs]

is that eastern beach weather station rain gauge tip amount set correctly?
seems to be recording 2x the amount of rain it should be

[David]

is that eastern beach weather station rain gauge tip amount set correctly?
seems to be recording 2x the amount of rain it should be

Although I did not think 15mm fell in that shower I definitely thought around 10-12mm was possible. There was a lot of surface flooding (brown water pouring down the street, and streams flowing out of driveways and off lawns). The rain was torrential (big drops too) and I know there was certainly more near school than the 6mm my gauge at home picked up. It was localised, and eastern beach easily could have been in the highest intensity area.

[tgsnoopy]

Wicked day.

Lots of lightning when driving down the coast this morning.

Wind gusts at about 8.30am Pukehina area were causing trucks to have to slow down to about 50 km/hr.

Very large hail in Whakatane about 9.30am. Had to stop several times for surface flooding serious enough to prevent me risking driving through it. Reports of stones getting near golf ball sized in Whakatane CBD.

Heard reports of two large waterspouts coming ashore near Opotiki when working at Kutarere near lunch time.

Lots of heavy showers with large hail driving through to Murupara this afternoon. Again I had to stop for surface flooding.

Certainly one out of the bag. Might be back down that way again tomorrow too. Poor car, over 500km a day!

[Manukau heads obs]

it certainly must have become more active the front in the BOP from what it was when it crossed over here!
this station in Ohope shows very heavy rain at one stage and gusty winds
http://ohopebeach.co.nz/WebCam/OhopeTop/parkweather.htm