Another Deep Low - Jan 21-22

Manukau heads obs · Fri 20/01/2017 15:13

lots of warnings and watches out for the next system due over the weekend
should be usefull rain for the upper north island hopefully, for the dry areas?

Nev · Unread post by **Nev** » Fri 20/01/2017 18:09

Yes, here's today's outlook for Sunday…

MetService - Severe Weather Outlook

Issued: 3:04pm Friday 20 Jan 2017
Valid from Sunday 22 January 2017 to Wednesday 25 January 2017

On Sunday, a deep low pressure system crosses the upper South Island from the Tasman Sea, while an associated front crosses northern and central New Zealand. This weather system will bring heavy rain and gales to much of the country for a time, and a Severe Weather Warning and Watch have already been issued for this event.

During Sunday, there is high confidence of significant heavy rain from the Marlborough Sounds to South Westland. There is moderate confidence of warnable amounts of rain for eastern Otago, the Tararua Range, the North Island high country from Mount Taranaki across to Taupo, and Bay of Plenty. There is low confidence rainfall amounts will meet warning criteria about Fiordland, inland parts of Otago and much of Canterbury as indicated on the chart. In addition, a period of north to northwest gales are expected to affect much of central and northern New Zealand on Sunday, and there is moderate confidence a severe gale warning will be required for Wairarapa, Wellington, Marlborough and the North Canterbury High Country for a time. Meanwhile, there is a broad area of low confidence that north to northwest gales will become severe about Buller, Nelson and the reminder of the North Island.

Cooler southwesterlies spread over New Zealand later Sunday as the low moves eastwards, then ease on Monday as a ridge of high pressure builds over northern New Zealand. There is moderate confidence south to southwest gales will become severe about exposed parts of eastern Otago and Banks Peninsula for a time on Sunday and Monday.
...

MetServce Severe Weather Outlook map for Jan 22.gif

Richard · Unread post by **Richard** » Fri 20/01/2017 18:38

What could be interesting for us in central SI is having low pressure of about 986hPa passing over during the afternoon, could be a chance of thunder maybe?

NZstorm · Unread post by **NZstorm** » Fri 20/01/2017 19:09

Richard wrote:What could be interesting for us in central SI is having low pressure of about 986hPa passing over during the afternoon, could be a chance of thunder maybe?

Looking too warm aloft Richard. GFS showing the 500mb -14C to 16C for your area.

NZ Thunderstorm Soc · Fri 20/01/2017 21:22

Richard wrote:What could be interesting for us in central SI is having low pressure of about 986hPa passing over during the afternoon, could be a chance of thunder maybe?

I thought that too Richard, but

Richard · Unread post by **Richard** » Fri 20/01/2017 21:34

NZstorm wrote:
Looking too warm aloft Richard. GFS showing the 500mb -14C to 16C for your area.

Bugger

i'll settle for a heavy shower then

Nev · Unread post by **Nev** » Sat 21/01/2017 07:44

Great headlne from the Wanganui Chronicle…

'Beware flying trampolines, warns Powerco'

Manukau heads obs · Sat 21/01/2017 07:50

Was an amazing sunrise this morning

NZstorm · Unread post by **NZstorm** » Sat 21/01/2017 08:44

I saw that sunrise Brian and thought 'red sky in the morning, sailors warning'!

Severe wind gust potential (120km/h) with the front that will sweep across the North Island tomorrow morning. Brief heavy rain with the front too.

Nev · Unread post by **Nev** » Sat 21/01/2017 08:45

Certainly was… yes, 'sailor's warning'…

Ak webcam surnse ℅ takeabreak - Jan 21.jpg

Nev · Unread post by **Nev** » Sat 21/01/2017 10:04

From this morn's MetService Severe Weather Warning

Severe northerly gales with gusts around 120 km/h are expected from Taranaki to Wellington and the Marlborough Sounds and damaging wind gusts of 140 km/h or more are possible for a time about South Taranaki, Whanganui and Taihape early Sunday morning.

GFS 850mb NZ Winds - Jan 22, 1am.png

jamie · Unread post by **jamie** » Sat 21/01/2017 16:17

I was out fishing at sunrise. Was great up here too.

NZstorm · Unread post by **NZstorm** » Sat 21/01/2017 16:59

I see some elevated thunderstorms have occurred on the warm front in the Tasman, west of the NI this afternoon.

spwill · Unread post by **spwill** » Sat 21/01/2017 17:54

The opportunity for some decent rain overnight/ morning then back into a dry pattern for northern NZ.

Windiest day of the year here with a fresh sometimes strong NE breeze, variable high cloud, mild.

Manukau heads obs · Sat 21/01/2017 20:04

heavy rain here now

Manukau heads obs · Sat 21/01/2017 20:22

just had one of the biggest pressure drops I have seen

4.2hpa in the last hour
make that 5 hpa now in the last hour!
wind picking up heaps too

tich · Unread post by **tich** » Sat 21/01/2017 20:22

Just a bit of rain as I got back into Chch late this afternoon.

I wonder if there's another unseasonable dump of snow due for the South Island mountains overnight and tomorrow, since the coming low and rain system seems to be moving in quickly in the wake of yesterday's cold snap, not allowing much rise in temperatures. (like in a winter warm advection scenario)

Manukau heads obs · Sat 21/01/2017 20:50

now 5.5hpa drop in the last hour
could be damaging northerly gales in exposed places

make that 6hpa drop in the last hour!

Richard · Unread post by **Richard** » Sat 21/01/2017 20:55

NZstorm wrote:
Richard wrote:What could be interesting for us in central SI is having low pressure of about 986hPa passing over during the afternoon, could be a chance of thunder maybe?
Looking too warm aloft Richard. GFS showing the 500mb -14C to 16C for your area.

What would attribute to the MetS giving my area now a moderate chance of a storm tomorrow

NZstorm · Unread post by **NZstorm** » Sat 21/01/2017 21:40

Very windy and wet here with power flashes. Quite an active warm front.

spwill · Unread post by **spwill** » Sat 21/01/2017 21:44

Some big wind gusts through here this evening, so that was a power flash I saw to the SW just now.

NZstorm · Unread post by **NZstorm** » Sat 21/01/2017 21:49

Yes plenty of power flashes.

Manukau heads obs · Sat 21/01/2017 21:51

60s kts at the Panmure Yacht club!
(wind will be funnelling down the estuary there)
lots of reports of power cuts in this area
and now in the south auckland area to

I did a big heads up 2 hours in advance..warnings could have come out...

spwill · Unread post by **spwill** » Sat 21/01/2017 21:54

Power poles have come down near my house, would have been the big flash I saw

David · Unread post by **David** » Sat 21/01/2017 21:54

Pressure has dropped 4 hPa in 25 minutes here just now!

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