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

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snowchaser01
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by snowchaser01 »

jamie wrote:What's the rugby ground like? Hope there is no flooding there?
I haven't heard. Not going to be a dry game though that's for sure
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by Storm Struck »

Yes and high tide is 3pm this afternoon so alot of those areas around the Heathcote and Avon rivers could well be flooded out even more so by then.
The Selwyn river is very close to the top of the second stopbank bridge on SH1 south, i would imagine evactuations are in place for Dunsandel and Burnham.
Just noticing a real increase on the radar now :-k , rain has got alot heavier here now and looks to be sleet mixed in the rain every so often with the strong wind gusts.
Canterbury, home of good rugby and severe storms
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by Razor »

Things are certainly going pear shaped in a lot of places now.

A side question, did this low 'officially' hit bomb status of 24hpa on 24 hours? Certainly hit 30 in 30 hours, and some!
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by RichyDunedin »

jamie wrote:What's the rugby ground like? Hope there is no flooding there?
Probably about as poor as Canterburys chances of winning tonight haha. \:D/
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by Razor »

Things getting hairy around Beckenham Library
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by snowstormwatcher »

NZstorm wrote:Interestingly the South Canterbury rain shadow still managed to show up a bit in this event.
Yeah only 40mm at Timaru airport for the event while 150mm+ at both Ashburton and Oamaru.. No significant rain here since last night.
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by Orion »

NZstorm wrote: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.
Right there with Niwa's "soupy subtropical stroke of air" :B
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by moylanr »

Orion wrote:
moylanr wrote:Ashburton has declared state of emergency.
A minor stream on the south boundary has burst out, farm driveways washed out, sirens during the day, manhole covers floating off
Do you have a source for that info?
Sorry, was from a trusted family member in the township ... who may have been flustered while shifting important documents into top cupboards...

This picture shows double the rain in Halswell today (bottom red line), & the pressure (top purple) which looks like more than 24kpa drop in 24h
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by NZ Thunderstorm Soc »

I would of love to see the Dunedin rainfalls with this event but I found out that the Rakaia and Southland radars
didn't pick up the rainfall very well.
Is Otago getting a radar?
Should be the next one if MS have a spare million bucks :-w
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by Chris W »

Biting wind out there now and still raining, though the rain is lighter now. Driving back from Hoon Hay the Heathcote is out of its banks in most places and there's high tide again at 3am. Hopefully things will improve quickly from early morning after the tide recedes.
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by RichyDunedin »

I've been away from Dunedin for a couple years now but before then I always found that they always had nothing on the radar unless there was a bad downpour or thunderstorm heading there then it would show dark blue briefly.
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by Richard »

NZ Thunderstorm Soc wrote: Is Otago getting a radar?
Should be the next one if MS have a spare million bucks :-w
Yes one is planned soon, cant be too far away from being made public
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by Nev »

David wrote:I asked Metservice on Twitter how deep this low got - they said 968 hPa was the lowest, over Le Bons Bay at 4pm yesterday.
Thanks for confirming that David. I figured Le Bons Bay would likely end up around 969-968 hPa based on Chch Aero's 970 hPa (claims of 964 hPa just seemed a little too implausible). However, I wonder if MS's timing might be a little out, as the lowest reading at NIWA's Diamond Harbour EWS was 969.3 hPh at midday on Friday, as was its Akaro EWS an hour later (by 4pm they were up to 971.5 hPa and 970.1 hPa respectively).

Also interesting that MS say that the low's centre was at its lowest over the Peninsula, then rose again as it moved out to sea. Not often you get a low bottoming-out over land and able to be measured by a properly calibrated official barometer.
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by Nev »

Razor wrote:A side question, did this low 'officially' hit bomb status of 24hpa on 24 hours? Certainly hit 30 in 30 hours, and some!
No… more like 24 hPa in 40 hrs, or about 16 hPa in 24 hrs. The low's most rapid intensification occurred on Thursday while its centre was still offshore in the Tasman.
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Re: Rapidly Deepening Low and Possible Snow Event July 20-22nd

Unread post by NZstorm »

NZ Thunderstorm Soc wrote:I
Should be the next one if MS have a spare million bucks :-w
Auckland City and north Waikato needs better radar coverage in my opinion. So maybe future investment could be replacing the Auckland radar and shifting it further south, after the Otago radar is installed. The government funds these things so hopefully more investment coming.
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