New Zealand Spring Weather

[J07]

First northwesterly storm, which you would expect a number of during the Spring months.

Yesterday there was lots of rain in the west, remaining dry in the east of course with 21C recorded in Kaikoura at midnight. Winds gusted to 140 km/h on the Rimutaka Hill Road (summit 555m), and to 120 km/h at lower levels.

Today we are in the last reaches of the storm and a cold southerly/southeasterly is working its way north.

The forecast maximum for Dunedin is 10C, and for Christchurch 23C.

Right now it's 21C in Christchurch and the change is a little way south with Timaru sitting on 11C (90 miles south).

Winds won't have helped the earthquake clean-up in Christchurch, but todays warm weather will probably be of use. However it does look quite chilly and grim from later today and into tomorrow.

[Thundery wintry showers]

Looking over the latest GFS runs, a wintry spell coming up for parts of the South Island? Plenty of southerly and south-westerly winds are showing together with some incursions of sub -5C 850hPa air.

[Buzzit]

About 10cm of snow has fallen in Southland in the last 24 hours.

Lots of power outages and road closures throughout both islands...

[J07]

Yes, it's been a pretty significant event for some places!

But the idea that it affected the whole country has been hyped up by the media. Canterbury, Marlborough, Wellington, Hawke's Bay and Gisborne have all seen glorious weather. Though it has been windy in Wellington we've had almost ceasless sunshine the last few days (because the wind is so westerly, as opposed to northwest). Whilst it was snowing in Invercargill, it was 18C in parts of Northland and Gisborne.

Story on the snow:

http://www.stuff.co.nz/national/4147391/Southland-braced-for-more-snow

As for wind, an official AWS on a hill just under 300m recorded sustained winds of 80 knots, with gusts of 105 knots.

[conor123]

The isobars llook very tightly packed over South Island in particular at the moment, and i know its 162hrs away but that sheer amount of such cold air heading for Tasmania & Australia looks quite surprising considering it should be starting to warm up now.

[J07]

Plenty of weather: http://www.stuff.co....hit-country

Dump of rain/snow over the Wellington region for about 5 hours this morning, the remainder of the day was perfectly sunny due to southwest orientation of the flow.

Edited September 22, 2010 by J07

[conor123]

New Zealand seems very interesting place for weather, though i will never understand how the UV index gets so shockingly high in the Summer compared to other places of similar latitude.

[cheeky_monkey]

arnt some areas on north island on the equivilant latitude to North africa or southern spain?

[J07]

New Zealand seems very interesting place for weather, though i will never understand how the UV index gets so shockingly high in the Summer compared to other places of similar latitude.

I think the most interesting thing is the interaction of topography with weather, to a much greater extent than in the UK, and also the speed with which the weather can change. The former is due to convenient and large mountain ranges that run perpendicular to prevailing winds. The latter thanks to the constant action in the southern ocean (it essentially never dies down) and further interaction with topography creating "southerly busters".

However, unlike the UK, NZ cannot really access un-modified polar air, which some would say is a shame!

The UV index is well described as "shockingly high". Roughly, the sun at Spring equinox is as strong, and often stronger than, the sun at the summer solstice in the UK. The UV index in summer is approximately 40% higher than equivalent latitudes in the northern hemisphere. eg you will see UV index of 10 in the Med at high summer, an equivalent day in NZ would yield 14. In the UK, the record high is 8, which you tend to exceed in NZ on every sunny day from October to March.

The UV index in winter is low, ranging from 1-3 across the country depending on conditions. But due to much cleaner air than the northern hemisphere, the scattering regime is altered which tends the light here towards the more energetic blue end of the spectrum, the result is that the sky is a more vivid blue than in the temperate NH, and the sun feels like it's burning you rather than warming you.

Much of this, apart from the quality of light, is not to be boasted about. I spent a long time in Europe this northern summer and it's wonderful how around the Med you can enjoy the sun without feeling like it's trying to destroy you. The summer sun in the UK is so weak that it may as well not exist.

arnt some areas on north island on the equivilant latitude to North africa or southern spain?

Yes, but they are cooler and more unsettled down here. Partly due to absence of permanent high pressure systems, the lack of a hot continent on the doorstep, cooler SSTs and a general tendency for westerlies to encroach further equatorward than they do in the NH (though in the southern summer the westerlies are notably reduced and in some summers almost entirely absent from the North Island due to prevailing sub tropical ridging).

[knocker]

Seasonal Climate Outlook: September-November 2010.

A mild La Niña spring on the way

A moderate La Niña is well-established in the tropical Pacific, and may strengthen further through the rest of 2010, says the NIWA National Climate Centre. La Niña conditions are likely to continue through the summer of 2010–11.

Spring temperatures are likely to be above average across the whole country. However, short-term cold snaps typical of spring will still occur from time to time.

Rainfall is likely to be near normal in most regions, averaged over the three months of spring (September, October, November). The north and east of the North Island is likely to experience normal or above normal rainfalls, according to the Centre’s latest seasonal outlook.

Soil moisture levels and stream flows are likely to be near normal in all regions, on average through the spring.

The National Climate Centre’s seasonal outlook states that mean sea level pressures are likely to be above normal near New Zealand, for spring as a whole.

http://www.niwa.co.nz/our-science/climate/publications/all/seasonal-climate-outlook/seasonal-climate-outlook-sep-nov-2010

[J07]

Seasonal Climate Outlook: September-November 2010.

A mild La Niña spring on the way

A moderate La Niña is well-established in the tropical Pacific, and may strengthen further through the rest of 2010, says the NIWA National Climate Centre. La Niña conditions are likely to continue through the summer of 2010–11.

Spring temperatures are likely to be above average across the whole country. However, short-term cold snaps typical of spring will still occur from time to time.

Rainfall is likely to be near normal in most regions, averaged over the three months of spring (September, October, November). The north and east of the North Island is likely to experience normal or above normal rainfalls, according to the Centre’s latest seasonal outlook.

Soil moisture levels and stream flows are likely to be near normal in all regions, on average through the spring.

The National Climate Centre’s seasonal outlook states that mean sea level pressures are likely to be above normal near New Zealand, for spring as a whole.

http://www.niwa.co.n...ok-sep-nov-2010

[Thundery wintry showers]

Might have some catching up to do then lol!

[Terminal Moraine]

New Zealand seems very interesting place for weather, though i will never understand how the UV index gets so shockingly high in the Summer compared to other places of similar latitude.

Probably something to do with the fact that the earth is at its nearest to the sun during the southern hemisphere summer, and furthest away during the northern hemisphere summer.

[J07]

Probably something to do with the fact that the earth is at its nearest to the sun during the southern hemisphere summer, and furthest away during the northern hemisphere summer.

Good point, January 4th is usually the closest the earth gets to the sun, and July 4th the furthest. I don't remember the difference, something like 4%, but it has a notable impact on insolation.

Corrected Metar from Christchurch, warm and dry and windy:

COR NZCH 260300Z 26019G31KT 220V290 CAVOK 22/M02 Q1004

[knocker]

Good point, January 4th is usually the closest the earth gets to the sun, and July 4th the furthest. I don't remember the difference, something like 4%, but it has a notable impact on insolation.

Corrected Metar from Christchurch, warm and dry and windy:

COR NZCH 260300Z 26019G31KT 220V290 CAVOK 22/M02 Q1004

Two other factors to take into account are lower ozone levels compared to the NH and a cleaner atmosphere. According to Dr Richard McKenzie, Senior Research Scientist at NIWA, the orbit variation will give 7 percent more UV than the northern summer, and the other two 10 and 20 percent respectively.

[J07]

Two other factors to take into account are lower ozone levels compared to the NH and a cleaner atmosphere. According to Dr Richard McKenzie, Senior Research Scientist at NIWA, the orbit variation will give 7 percent more UV than the northern summer, and the other two 10 and 20 percent respectively.

Very interesting to get that breakdown. Interesting that quality of light is the most important factor. It's pretty poor in Europe but I didn't realise it contributed quite so strongly to UV reduction.

[knocker]

Very interesting to get that breakdown. Interesting that quality of light is the most important factor. It's pretty poor in Europe but I didn't realise it contributed quite so strongly to UV reduction.

Nor did I. I must admit I would have opted for less ozone as being the greater contributor.

[J07]

About half a million lambs died down south during the snow storms this month. But a few days later, warmth fed into the country with northern towns reaching 25C.

Once this trough moves through later today we are briefly in a southwest flow, then the following high looks to be almost stationary over the country throughout next week along with a nice upper ridge.

October is normally a mobile westerly month (in fact, the most mobile westerly month) so it is quite unusual to see this happen. Perhaps a reflection of strong La Nina conditions.

[J07]

Been very cold and windy today across the country. Snow to 400m in the south of the North Island and 200m in the South Island. Even Auckland has been hit pretty hard with a mere 8C there at midday! In October that is really cold.

[knocker]

That's a fair old depression forecast south west of South Island on the 16th. If I read it correctly 930mb.

[J07]

Yes it deepened very quickly also.

During our latest cold outbreak, Milford Sound, one of the wettest places in the world outside the tropics (7000mm of rain a year) recorded a temperature of 19.5C with a dewpoint of -11.4C, giving an RH of 11%! It was because the typical northwesterlies were replaced by a southeasterly flow. Shortly afterwards they got their "fiord breeze" and the dewpoint jumped by 20C in an hour (temperature dropping by 4C).

[conor123]

It does seem that you've had a pretty poor Spring thus far though the outlook for the next few days looks warmer and drier at least, though its rather surprising looking at the charts today seeing 0c 850pHa getting as far as 28S on Saturday, which would be the equivalent of as far south as Florida or North Africa in the middle of April which seems impossible.

[J07]

It does seem that you've had a pretty poor Spring thus far though the outlook for the next few days looks warmer and drier at least, though its rather surprising looking at the charts today seeing 0c 850pHa getting as far as 28S on Saturday, which would be the equivalent of as far south as Florida or North Africa in the middle of April which seems impossible.

Depends on where you are. Plenty of places have had a good Spring, Christchurch being notable with a long week + period of temperatures reaching 20C. Wellington had a very wet September but still above normal sunshine. There's also been warm temperatures recorded already, but no repeat of the very early 30C of last year.

I've seen cold polar outbreaks streaming into the north Pacific tropics last winter but I don't know about the 850 temperatures there.

The SH lacks severe cold but cold snaps can occur for much of the year and push a fair way north. I think the westerlies are a bit further equatorward in this hemisphere than in the NH. Cold fronts can reach Fiji (around 18S) in the winter month, though they have lost their temperature gradient by then and just dry out the air.

Sept summary: http://www.niwa.co.nz/our-science/climate/publications/all/cs/monthly/climate-summary-for-september-2010

Wet and wild westerlies

• Rainfall: Double normal rainfall in the southwest of North Island, the north and northwest of South Island, and around Invercargill. Many September rainfall records broken in these areas. Very wet in most other regions, but dry in south Canterbury and coastal Gisborne.
• Temperatures: Above average in the north and east of the North Island, and the eastern South Island. Well below average in the west and south of the South Island.
• Sunshine: Well below normal sunshine hours in western areas of both islands.

September 2010 was characterised by extremely low pressures over New Zealand, bringing wild westerly winds. The effect of the stronger-than-normal westerly winds during September was very clear – rainfall was record high or well above average, and sunshine hours were well below average, in western areas of both islands. It was also much cooler than usual in the west and south of the South Island, but warmer than average in eastern areas; both are trademarks of enhanced westerly circulation.
September rainfall was more than double normal (at least 200 percent) in the southwest of the North Island, from Turangi to Taranaki to the Kapiti Coast, as well as the north and northwest of the South Island – including Nelson, Blenheim and Buller – and around Invercargill. Many locations in these areas experienced their wettest September on record. Most other regions around the country also received above normal rainfall (between 120 and 150 percent of normal). The only exceptions were eastern Northland and coastal north Canterbury (which experienced near normal rainfall), and Gisborne and south Canterbury (which received less than 50 percent of usual September falls).
Extremely warm temperatures affected the country at both the start and end of the month – but an intense southwesterly event from the 17th until 24th brought snow to very low levels in the far south, and record low temperatures there. Overall, monthly mean temperatures were above average (between 0.5°C and 1.2°C above average) in eastern regions of both islands, as well as from Taranaki down to Wellington. In contrast, much of the west and south of the South Island experienced below average temperatures (1.2°C to 0.5°C below average). The New Zealand national average temperature was 10.9°C (0.5°C above the 1971–2000 September average).
Well below average sunshine totals (less than 75 percent of normal) were recorded in western areas of both islands, due to the stronger-than-normal westerly winds during September. In contrast, above normal sunshine hours were received in south Canterbury (between 110 and 125 percent of normal). In most other regions, September sunshine totals were closer to normal (ranging between 90 and 110 percent of normal).

Further Highlights:

• The highest temperature was 24.6°C, recorded at Kaikoura on the 6th (near record).
• The lowest temperature was -6.2°C, recorded at Lake Tekapo on the 22nd.
• The highest 1-day rainfall was 135.0 mm recorded at Milford Sound on the 5th.
• The highest wind gust was 204 km/hr, recorded at Cape Turnagain on the 23rd.
• Of the six main centres, Tauranga was the warmest, Dunedin the coolest, Christchurch the sunniest and driest, and Wellington the wettest.

Sept summary: http://www.niwa.co.nz/our-science/climate/publications/all/cs/monthly/climate-summary-for-september-2010

Wet and wild westerlies

• Rainfall: Double normal rainfall in the southwest of North Island, the north and northwest of South Island, and around Invercargill. Many September rainfall records broken in these areas. Very wet in most other regions, but dry in south Canterbury and coastal Gisborne.
• Temperatures: Above average in the north and east of the North Island, and the eastern South Island. Well below average in the west and south of the South Island.
• Sunshine: Well below normal sunshine hours in western areas of both islands.

September 2010 was characterised by extremely low pressures over New Zealand, bringing wild westerly winds. The effect of the stronger-than-normal westerly winds during September was very clear – rainfall was record high or well above average, and sunshine hours were well below average, in western areas of both islands. It was also much cooler than usual in the west and south of the South Island, but warmer than average in eastern areas; both are trademarks of enhanced westerly circulation.
September rainfall was more than double normal (at least 200 percent) in the southwest of the North Island, from Turangi to Taranaki to the Kapiti Coast, as well as the north and northwest of the South Island – including Nelson, Blenheim and Buller – and around Invercargill. Many locations in these areas experienced their wettest September on record. Most other regions around the country also received above normal rainfall (between 120 and 150 percent of normal). The only exceptions were eastern Northland and coastal north Canterbury (which experienced near normal rainfall), and Gisborne and south Canterbury (which received less than 50 percent of usual September falls).
Extremely warm temperatures affected the country at both the start and end of the month – but an intense southwesterly event from the 17th until 24th brought snow to very low levels in the far south, and record low temperatures there. Overall, monthly mean temperatures were above average (between 0.5°C and 1.2°C above average) in eastern regions of both islands, as well as from Taranaki down to Wellington. In contrast, much of the west and south of the South Island experienced below average temperatures (1.2°C to 0.5°C below average). The New Zealand national average temperature was 10.9°C (0.5°C above the 1971–2000 September average).
Well below average sunshine totals (less than 75 percent of normal) were recorded in western areas of both islands, due to the stronger-than-normal westerly winds during September. In contrast, above normal sunshine hours were received in south Canterbury (between 110 and 125 percent of normal). In most other regions, September sunshine totals were closer to normal (ranging between 90 and 110 percent of normal).

Further Highlights:

• The highest temperature was 24.6°C, recorded at Kaikoura on the 6th (near record).
• The lowest temperature was -6.2°C, recorded at Lake Tekapo on the 22nd.
• The highest 1-day rainfall was 135.0 mm recorded at Milford Sound on the 5th.
• The highest wind gust was 204 km/hr, recorded at Cape Turnagain on the 23rd.
• Of the six main centres, Tauranga was the warmest, Dunedin the coolest, Christchurch the sunniest and driest, and Wellington the wettest.

Sept summary: http://www.niwa.co.nz/our-science/climate/publications/all/cs/monthly/climate-summary-for-september-2010

Wet and wild westerlies

• Rainfall: Double normal rainfall in the southwest of North Island, the north and northwest of South Island, and around Invercargill. Many September rainfall records broken in these areas. Very wet in most other regions, but dry in south Canterbury and coastal Gisborne.
• Temperatures: Above average in the north and east of the North Island, and the eastern South Island. Well below average in the west and south of the South Island.
• Sunshine: Well below normal sunshine hours in western areas of both islands.

September 2010 was characterised by extremely low pressures over New Zealand, bringing wild westerly winds. The effect of the stronger-than-normal westerly winds during September was very clear – rainfall was record high or well above average, and sunshine hours were well below average, in western areas of both islands. It was also much cooler than usual in the west and south of the South Island, but warmer than average in eastern areas; both are trademarks of enhanced westerly circulation.
September rainfall was more than double normal (at least 200 percent) in the southwest of the North Island, from Turangi to Taranaki to the Kapiti Coast, as well as the north and northwest of the South Island – including Nelson, Blenheim and Buller – and around Invercargill. Many locations in these areas experienced their wettest September on record. Most other regions around the country also received above normal rainfall (between 120 and 150 percent of normal). The only exceptions were eastern Northland and coastal north Canterbury (which experienced near normal rainfall), and Gisborne and south Canterbury (which received less than 50 percent of usual September falls).
Extremely warm temperatures affected the country at both the start and end of the month – but an intense southwesterly event from the 17th until 24th brought snow to very low levels in the far south, and record low temperatures there. Overall, monthly mean temperatures were above average (between 0.5°C and 1.2°C above average) in eastern regions of both islands, as well as from Taranaki down to Wellington. In contrast, much of the west and south of the South Island experienced below average temperatures (1.2°C to 0.5°C below average). The New Zealand national average temperature was 10.9°C (0.5°C above the 1971–2000 September average).
Well below average sunshine totals (less than 75 percent of normal) were recorded in western areas of both islands, due to the stronger-than-normal westerly winds during September. In contrast, above normal sunshine hours were received in south Canterbury (between 110 and 125 percent of normal). In most other regions, September sunshine totals were closer to normal (ranging between 90 and 110 percent of normal).

Further Highlights:

• The highest temperature was 24.6°C, recorded at Kaikoura on the 6th (near record).
• The lowest temperature was -6.2°C, recorded at Lake Tekapo on the 22nd.
• The highest 1-day rainfall was 135.0 mm recorded at Milford Sound on the 5th.
• The highest wind gust was 204 km/hr, recorded at Cape Turnagain on the 23rd.
• Of the six main centres, Tauranga was the warmest, Dunedin the coolest, Christchurch the sunniest and driest, and Wellington the wettest.

Sept summary: http://www.niwa.co.nz/our-science/climate/publications/all/cs/monthly/climate-summary-for-september-2010

Wet and wild westerlies

• Rainfall: Double normal rainfall in the southwest of North Island, the north and northwest of South Island, and around Invercargill. Many September rainfall records broken in these areas. Very wet in most other regions, but dry in south Canterbury and coastal Gisborne.
• Temperatures: Above average in the north and east of the North Island, and the eastern South Island. Well below average in the west and south of the South Island.
• Sunshine: Well below normal sunshine hours in western areas of both islands.

September 2010 was characterised by extremely low pressures over New Zealand, bringing wild westerly winds. The effect of the stronger-than-normal westerly winds during September was very clear – rainfall was record high or well above average, and sunshine hours were well below average, in western areas of both islands. It was also much cooler than usual in the west and south of the South Island, but warmer than average in eastern areas; both are trademarks of enhanced westerly circulation.
September rainfall was more than double normal (at least 200 percent) in the southwest of the North Island, from Turangi to Taranaki to the Kapiti Coast, as well as the north and northwest of the South Island – including Nelson, Blenheim and Buller – and around Invercargill. Many locations in these areas experienced their wettest September on record. Most other regions around the country also received above normal rainfall (between 120 and 150 percent of normal). The only exceptions were eastern Northland and coastal north Canterbury (which experienced near normal rainfall), and Gisborne and south Canterbury (which received less than 50 percent of usual September falls).
Extremely warm temperatures affected the country at both the start and end of the month – but an intense southwesterly event from the 17th until 24th brought snow to very low levels in the far south, and record low temperatures there. Overall, monthly mean temperatures were above average (between 0.5°C and 1.2°C above average) in eastern regions of both islands, as well as from Taranaki down to Wellington. In contrast, much of the west and south of the South Island experienced below average temperatures (1.2°C to 0.5°C below average). The New Zealand national average temperature was 10.9°C (0.5°C above the 1971–2000 September average).
Well below average sunshine totals (less than 75 percent of normal) were recorded in western areas of both islands, due to the stronger-than-normal westerly winds during September. In contrast, above normal sunshine hours were received in south Canterbury (between 110 and 125 percent of normal). In most other regions, September sunshine totals were closer to normal (ranging between 90 and 110 percent of normal).

Further Highlights:

• The highest temperature was 24.6°C, recorded at Kaikoura on the 6th (near record).
• The lowest temperature was -6.2°C, recorded at Lake Tekapo on the 22nd.
• The highest 1-day rainfall was 135.0 mm recorded at Milford Sound on the 5th.
• The highest wind gust was 204 km/hr, recorded at Cape Turnagain on the 23rd.
• Of the six main centres, Tauranga was the warmest, Dunedin the coolest, Christchurch the sunniest and driest, and Wellington the wettest.

Sept summary: http://www.niwa.co.nz/our-science/climate/publications/all/cs/monthly/climate-summary-for-september-2010

Wet and wild westerlies

• Rainfall: Double normal rainfall in the southwest of North Island, the north and northwest of South Island, and around Invercargill. Many September rainfall records broken in these areas. Very wet in most other regions, but dry in south Canterbury and coastal Gisborne.
• Temperatures: Above average in the north and east of the North Island, and the eastern South Island. Well below average in the west and south of the South Island.
• Sunshine: Well below normal sunshine hours in western areas of both islands.

September 2010 was characterised by extremely low pressures over New Zealand, bringing wild westerly winds. The effect of the stronger-than-normal westerly winds during September was very clear – rainfall was record high or well above average, and sunshine hours were well below average, in western areas of both islands. It was also much cooler than usual in the west and south of the South Island, but warmer than average in eastern areas; both are trademarks of enhanced westerly circulation.
September rainfall was more than double normal (at least 200 percent) in the southwest of the North Island, from Turangi to Taranaki to the Kapiti Coast, as well as the north and northwest of the South Island – including Nelson, Blenheim and Buller – and around Invercargill. Many locations in these areas experienced their wettest September on record. Most other regions around the country also received above normal rainfall (between 120 and 150 percent of normal). The only exceptions were eastern Northland and coastal north Canterbury (which experienced near normal rainfall), and Gisborne and south Canterbury (which received less than 50 percent of usual September falls).
Extremely warm temperatures affected the country at both the start and end of the month – but an intense southwesterly event from the 17th until 24th brought snow to very low levels in the far south, and record low temperatures there. Overall, monthly mean temperatures were above average (between 0.5°C and 1.2°C above average) in eastern regions of both islands, as well as from Taranaki down to Wellington. In contrast, much of the west and south of the South Island experienced below average temperatures (1.2°C to 0.5°C below average). The New Zealand national average temperature was 10.9°C (0.5°C above the 1971–2000 September average).
Well below average sunshine totals (less than 75 percent of normal) were recorded in western areas of both islands, due to the stronger-than-normal westerly winds during September. In contrast, above normal sunshine hours were received in south Canterbury (between 110 and 125 percent of normal). In most other regions, September sunshine totals were closer to normal (ranging between 90 and 110 percent of normal).

Further Highlights:

• The highest temperature was 24.6°C, recorded at Kaikoura on the 6th (near record).
• The lowest temperature was -6.2°C, recorded at Lake Tekapo on the 22nd.
• The highest 1-day rainfall was 135.0 mm recorded at Milford Sound on the 5th.
• The highest wind gust was 204 km/hr, recorded at Cape Turnagain on the 23rd.
• Of the six main centres, Tauranga was the warmest, Dunedin the coolest, Christchurch the sunniest and driest, and Wellington the wettest.

Sept summary: http://www.niwa.co.nz/our-science/climate/publications/all/cs/monthly/climate-summary-for-september-2010

Wet and wild westerlies

• Rainfall: Double normal rainfall in the southwest of North Island, the north and northwest of South Island, and around Invercargill. Many September rainfall records broken in these areas. Very wet in most other regions, but dry in south Canterbury and coastal Gisborne.
• Temperatures: Above average in the north and east of the North Island, and the eastern South Island. Well below average in the west and south of the South Island.
• Sunshine: Well below normal sunshine hours in western areas of both islands.

September 2010 was characterised by extremely low pressures over New Zealand, bringing wild westerly winds. The effect of the stronger-than-normal westerly winds during September was very clear – rainfall was record high or well above average, and sunshine hours were well below average, in western areas of both islands. It was also much cooler than usual in the west and south of the South Island, but warmer than average in eastern areas; both are trademarks of enhanced westerly circulation.
September rainfall was more than double normal (at least 200 percent) in the southwest of the North Island, from Turangi to Taranaki to the Kapiti Coast, as well as the north and northwest of the South Island – including Nelson, Blenheim and Buller – and around Invercargill. Many locations in these areas experienced their wettest September on record. Most other regions around the country also received above normal rainfall (between 120 and 150 percent of normal). The only exceptions were eastern Northland and coastal north Canterbury (which experienced near normal rainfall), and Gisborne and south Canterbury (which received less than 50 percent of usual September falls).
Extremely warm temperatures affected the country at both the start and end of the month – but an intense southwesterly event from the 17th until 24th brought snow to very low levels in the far south, and record low temperatures there. Overall, monthly mean temperatures were above average (between 0.5°C and 1.2°C above average) in eastern regions of both islands, as well as from Taranaki down to Wellington. In contrast, much of the west and south of the South Island experienced below average temperatures (1.2°C to 0.5°C below average). The New Zealand national average temperature was 10.9°C (0.5°C above the 1971–2000 September average).
Well below average sunshine totals (less than 75 percent of normal) were recorded in western areas of both islands, due to the stronger-than-normal westerly winds during September. In contrast, above normal sunshine hours were received in south Canterbury (between 110 and 125 percent of normal). In most other regions, September sunshine totals were closer to normal (ranging between 90 and 110 percent of normal).

Further Highlights:

• The highest temperature was 24.6°C, recorded at Kaikoura on the 6th (near record).
• The lowest temperature was -6.2°C, recorded at Lake Tekapo on the 22nd.
• The highest 1-day rainfall was 135.0 mm recorded at Milford Sound on the 5th.
• The highest wind gust was 204 km/hr, recorded at Cape Turnagain on the 23rd.
• Of the six main centres, Tauranga was the warmest, Dunedin the coolest, Christchurch the sunniest and driest, and Wellington the wettest.

[J07]

Yesterday in Milford Sound, temperature was 22C, dewpoints -11C. Relative humidity of 10%. The wind at the surface was coming from the northwest.

[Kentish Kiwi]

Yesterday in Milford Sound, temperature was 22C, dewpoints -11C. Relative humidity of 10%. The wind at the surface was coming from the northwest.

Just wanted to pop in and say that I really appreciate these updates you do J07. Obviously a topic of particular interest to me and its very nice to be able to keep up with the weather all the way down there, I often look at weatherwatch.co.nz which is quite a good read.

Its also very interesting to read the discussions of the differences between NZ and the UK in terms of climate and other meteorological factors (UV etc), I get rather tired of people saying to me that NZ's climate is 'just the same as here (the UK)' or when I complain how cold it is, remarking 'aren't you used to this though with it being so snowy and cold in NZ?' obviously thinking Lord of the Rings is an accurate representation of NZ's climate! :lol:

Looking over the latest GFS runs, a wintry spell coming up for parts of the South Island? Plenty of southerly and south-westerly winds are showing together with some incursions of sub -5C 850hPa air.

Where abouts can you view GFS charts for NZ/Australasia TWS? I've looked around a bit but can't find anything remotely comparable to the netweather chart viewer or wetterzentrale??