Rapidly Deepening Low and Possible Snow Event July 20-22nd

NZstorm · Unread post by **NZstorm** » Sat 22/07/2017 09:13

From NZ Herald

The weather system causing nasty conditions across the country is now in a "death spiral" and should wear itself out by tomorrow morning, forecasters say.

The term 'death spiral' is a new one for weather forecasting.

Nev · Unread post by **Nev** » Sat 22/07/2017 09:25

A few numbers from MS this morn…

On Facebook MetService wrote:Here is what is our radar picked up over the 24hrs to 8am this morning. The purple areas registered over 100mm. 220mm captured on the hills north of Dunedin. 162mm Oamaru, 154mm Waitati, 124mm Darfield, 120mm Porters Pass, 118mm Geraldine, 116mm Dunedin City, 115mm Methven, 104mm Ashburton, ... ^JR

MetService Chch radar 24 hr accum. rainfall - Jul 22, 8am.jpg

RichyDunedin · Unread post by **RichyDunedin** » Sat 22/07/2017 09:28

Hundreds of houses evacuated from flooding and slips in the Dunedin/Taieri area now. All major roads in the area closed too. The flooding seems not as bad as 2015 in south Dunedin but one of the highest on record on the Taieri Plains. Hopefully the Highlanders can catch a flight to Christchurch today haha.

mikestormchaser · Unread post by **mikestormchaser** » Sat 22/07/2017 09:41

We lost power here this morning. Good excuse to lite the fire at 9am in the morning. Not warm out either at around 4C raining and a very strong cold S

RWood · Unread post by **RWood** » Sat 22/07/2017 09:50

Nev wrote:A few numbers from MS this morn…

On Facebook MetService wrote:Here is what is our radar picked up over the 24hrs to 8am this morning. The purple areas registered over 100mm. 220mm captured on the hills north of Dunedin. 162mm Oamaru, 154mm Waitati, 124mm Darfield, 120mm Porters Pass, 118mm Geraldine, 116mm Dunedin City, 115mm Methven, 104mm Ashburton, ... ^JR

MetService Chch radar 24 hr accum. rainfall - Jul 22, 8am.jpg

119mm at Musselburgh in the June 4 1980 event - and the infamous April 22 1923 event registered 229mm there. In May 1923 the exceptional North Canterbury flood occurred, discussed in these pages a few years back - and revived in June 2015.

spwill · Unread post by **spwill** » Sat 22/07/2017 09:56

With regard to the lower Taieri Plains I think the worst of the flooding will be yet to come as it will take time for the water to come off the hills via the Taieri river and pond into the area.

snowchaser01 · Unread post by **snowchaser01** » Sat 22/07/2017 10:30

Wild morning out there. Gusty southerlues, heavy rain which seems to be setting in on the radar and it's not too much more than 6deg. Mt Hutt will be loving this but surely the avalanchr risk is through the roof?

melja · Unread post by **melja** » Sat 22/07/2017 10:32

Nothing north of Chch

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snowchaser01 · Unread post by **snowchaser01** » Sat 22/07/2017 10:34

melja wrote:Nothing north of Chch

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I'd say it will shift north this morning.

Razor · Unread post by **Razor** » Sat 22/07/2017 10:40

Absolutely tipping it down here. Over 30mm now, more than yesterdays total. I'd had a feeling the second wave would hit us more here

Razor · Unread post by **Razor** » Sat 22/07/2017 10:55

Interestingly for the last hour the wind has turned back to Westerly with even heavier rain. The Heatcote River is well breached in all the usual places noe

cbm · Unread post by **cbm** » Sat 22/07/2017 11:02

Razor wrote:Absolutely tipping it down here. Over 30mm now, more than yesterdays total. I'd had a feeling the second wave would hit us more here

I'm about to board a flight to Christchurch. Just transiting on the way to Queenstown. Going to be interesting.

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David · Unread post by **David** » Sat 22/07/2017 11:19

I asked Metservice on Twitter how deep this low got - they said 968 hPa was the lowest, over Le Bons Bay at 4pm yesterday.

Chris W · Unread post by **Chris W** » Sat 22/07/2017 11:35

Christchurch City Council are now asking people to avoid flushing toilets and showering, as many wastewater pump stations have been flooded and sewerage is overflowing. High tide is blocking up the rivers.

The extreme low pressure yesterday also produced a storm surge in the Southshore estuary.

NZstorm · Unread post by **NZstorm** » Sat 22/07/2017 11:37

Interestingly the South Canterbury rain shadow still managed to show up a bit in this event.

Razor · Unread post by **Razor** » Sat 22/07/2017 11:53

State of Emergency declared for part of the Selwyn District. The Selwyn River has breached I believe the areas around Selwyn Huts worst affected

UPDATE: State of Emergency now declared in Christchurch, major problem looming with high tide. Avoid unnecessary travel

Dean. · Unread post by **Dean.** » Sat 22/07/2017 12:19

Just tipped out 150mm here since yesterday morning

Richard · Unread post by **Richard** » Sat 22/07/2017 12:24

Been very little rain here for 12 hours, even been out mixing concrete this morning, thankfully not setting it outside though

Richard · Unread post by **Richard** » Sat 22/07/2017 12:27

i wondering if its raining a lot more on the SW side of Banks Peninsular or is the radar not picking rain on the NE side

Razor · Unread post by **Razor** » Sat 22/07/2017 12:38

Over 40mm here now in last 7 hours. Selwyn State if Emergency now extended to District wide

And yes Richard it does seem to be pushing in the SW side of the Peninsula and inland from there

Richard · Unread post by **Richard** » Sat 22/07/2017 12:39

The MetService Culverden station has not recorded yesterdays rainfall correctly, only showing 8.6 while 50mm was recorded here and Waiau 48mm, something is not right there

melja · Unread post by **melja** » Sat 22/07/2017 12:42

Like you Richard very little here still with only 3mm since midnight.

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Bradley · Unread post by **Bradley** » Sat 22/07/2017 13:08

Went for a drive up to Porters Pass and some decent snow falling there now with around 3-5cm on the ground, the snow line seems to be about 700m at the moment...

snowchaser01 · Unread post by **snowchaser01** » Sat 22/07/2017 13:09

Serious flooding around Christchurch's river suburbs now. And I'm not liking the look for what's coming in on the radar!! Right at high tide time too...

jamie · Unread post by **jamie** » Sat 22/07/2017 13:35

What's the rugby ground like? Hope there is no flooding there?

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