With reference to December 1957 flood levels - an excerpt from the Met. summary :
"Rainfall: Rainfall was above normal, except in northern and eastern districts of the North Island, the Waimea Valley of Nelson, and the Kaikoura coast. In the South Island high country it was twice as wet as usual. Bay of Plenty, Gisborne and Hawkes Bay received less than half the normal value; Gisborne city was one of the driest places, with only a third of an inch. In the Alps it was the wettest of any month in over 50 years of records. Arthurs Pass received 47”; and the Hermitage, Mt Cook, received 51”, of which 19.34” fell on the 26th. Serious flooding disrupted road and rail transport across the Alps on at least three occasions, namely the 4th, 14th and 26th. On the last occasion the township of Otira was under water and a considerable portion of the railway track was washed out. At the same time major floods developed in several Canterbury and Westland rivers, especially the Rakaia and Waimakariri."
December 1957 is still the wettest December at Arthurs Pass, but its monthly record is now held by November 1994. The all-months record-holder at the Hermitage is now December 1979 - 1447 mm, boosted by 537mm on the 2nd. Tekapo and Ohau still have 1957 as their wettest December. The period October 1957 to March 1958 was exceptionally wet for the West Coast, Fiordland and the Alps - Milford Sound had more than its annual average in that time, and recorded 10015mm for the 12 months ending May 1958.
Re: Rain/ Snow / Flooding SI 8/9 Nov 2018
Posted: Fri 09/11/2018 19:55
by Richard
Some amazing figures there Rupert
Re: Rain/ Snow / Flooding SI 8/9 Nov 2018
Posted: Fri 09/11/2018 20:37
by Chris W
Yes, staggering amounts of rain. That also applies to the past two days though, just it hasn't had the same impact on the Waimak.
Re: Rain/ Snow / Flooding SI 8/9 Nov 2018
Posted: Fri 09/11/2018 20:55
by TonyT
RWood wrote: ↑Fri 09/11/2018 19:23
With reference to December 1957 flood levels - an excerpt from the Met. summary :
"Rainfall: Rainfall was above normal, except in northern and eastern districts of the North Island, the Waimea Valley of Nelson, and the Kaikoura coast. In the South Island high country it was twice as wet as usual. Bay of Plenty, Gisborne and Hawkes Bay received less than half the normal value; Gisborne city was one of the driest places, with only a third of an inch. In the Alps it was the wettest of any month in over 50 years of records. Arthurs Pass received 47”; and the Hermitage, Mt Cook, received 51”, of which 19.34” fell on the 26th. Serious flooding disrupted road and rail transport across the Alps on at least three occasions, namely the 4th, 14th and 26th. On the last occasion the township of Otira was under water and a considerable portion of the railway track was washed out. At the same time major floods developed in several Canterbury and Westland rivers, especially the Rakaia and Waimakariri."
December 1957 is still the wettest December at Arthurs Pass, but its monthly record is now held by November 1994. The all-months record-holder at the Hermitage is now December 1979 - 1447 mm, boosted by 537mm on the 2nd. Tekapo and Ohau still have 1957 as their wettest December. The period October 1957 to March 1958 was exceptionally wet for the West Coast, Fiordland and the Alps - Milford Sound had more than its annual average in that time, and recorded 10015mm for the 12 months ending May 1958.
And looking at the peak river flows for the Waimak in the graph on p2 of this thread, both 1994 and 1979 had peak flows higher than today's level.
Re: Rain/ Snow / Flooding SI 8/9 Nov 2018
Posted: Fri 09/11/2018 22:05
by spwill
The Mackenzie and North Otago hydro lakes must have got a good top up, Mt Cook showing 244mm and Twizel 95.4mm from this event.
Re: Rain/ Snow / Flooding SI 8/9 Nov 2018
Posted: Fri 09/11/2018 23:31
by Simon Culling
Photos on this link of settling snow in Mt Somers, which is at between 380-390m amsl.
Are warm advection snow events becoming more common? I suspect they are, this was the third warm advection snow event this spring in the South Island. And last spring there was an event on November 11th.
Re: Rain/ Snow / Flooding SI 8/9 Nov 2018
Posted: Sat 10/11/2018 07:14
by Richard
Just had a look at the highest mountains west of here (about 1500 m) no snow at all, so all that warm advection snow was to the south.
Sudden warming at both poles across the layers is moving the Polar Jetstream further north (south for NH)during late Autumn and Spring and that combines with higher SST's. Both Stratospheric and Troposphere polar vortex have shown significant signs of weaken during these times in recent years.
Re: Rain/ Snow / Flooding SI 8/9 Nov 2018
Posted: Sat 10/11/2018 08:21
by RWood
Simon Culling wrote: ↑Fri 09/11/2018 23:31
Photos on this link of settling snow in Mt Somers, which is at between 380-390m amsl.
As a reference point, the 2-day record for NZ sites is 1049mm at Cropp Waterfall.
Re: Rain/ Snow / Flooding SI 8/9 Nov 2018
Posted: Sat 10/11/2018 09:31
by Dean.
Inland Mid Canterbury a picture this morning
Re: Rain/ Snow / Flooding SI 8/9 Nov 2018
Posted: Sat 10/11/2018 10:04
by harleyb
Impressive rainfall!
Speaking of records, I had to trawl through some Taranaki rainfall data for a job a while ago and it included this for October 1998 at North Egmont... 2.8 metres for the month & if I recall correctly over 11 metres for the 1998 year.
Speaking of records, I had to trawl through some Taranaki rainfall data for a job a while ago and it included this for October 1998 at North Egmont... 2.8 metres for the month & if I recall correctly over 11 metres for the 1998 year.
Pretty close - 10765mm at North Egmont in 1998. Many stations set an all-months rainfall record in October 1998. The NZ record for a month is 2927mm at Cropp Waterfall in December 1995, and it also holds the 31-day record of 3813mm during a portion of October-November 1999.
Re: Rain/ Snow / Flooding SI 8/9 Nov 2018
Posted: Sat 10/11/2018 21:46
by Simon Culling
This tweet from MetService gives a satellite view of the extent of the snowfall - I wonder how accurate it is, especially when the snow cover is very thin in places?
This would be equivalent to a snowfall on the higher hills (>300m) here in the UK in May - which in recent years has not been a common occurrence. The last time I can remember a snow cover to low ground in May was on 2nd May 1979 - which was the day Mrs Thatcher was elected PM!
Re: Rain/ Snow / Flooding SI 8/9 Nov 2018
Posted: Sat 10/11/2018 23:51
by Thunder081
Very interesting on those highest rainfall months here's a satellite time lapse of October 1998