Warm Days

[wembley]

Are there any stats on how many warm days (days over 25 degrees) per annum various places in NZ gets?

Just academic interest.

[treetop]

Metservice if your willing to join up and pay for the data. Gisbourne to Just south of Hastings would be the Highest . If you go just inland from any of these these centers you could add another 10 or so days at least because of sea breeze cooling.Readings are often taken after 12 pm when the Temp can be the highest between 11 and Noon on some days before the sea breeze gets going. If you want to be accurate its quite complicated..

[NZstorm]

There is quite large seasonal variation from year to year.

For example I had a look at 25C+ days for Queenstown in January and came up with a range of 1day to 20days.
But 8 or 9 days in January might be considered normal.

[wembley]

I had a book about NZ geography which covered all sorts of subjects such as economy, transport, land use and yes, climate. There was a chart in the book which showed how many 25+ degree days per annum various parts of NZ showed, in map format and the areas with the most days were up north, Christchurch and Central Otago. I think Dunedin was in one of the upper bands in spite of it's January average being only 19 degrees, possibly due to norwesters?

[Nev]

Cliflo has monthly 'days over 25C' data, from which longterm averages can be calculated, although along with a fair amount of missing data having to be compensated for, this could be quite time consuming.

I've put together a (guide only) short list of some key cities/towns based on that data:

1981-2010 average days-per-year over 25°C
30.1 … Kerikeri EWS
18.8 … Auckland, Mangere
25.3 … Auckland Aero
23.1 … Tauranga Aero
28.7 … Hamilton, Ruakura
33.5 … Hamilton Aero
43.2 … Napier, Nelson Park
37.1 … Napier Aero
49.7 … Gisborne Aero
02.8 … Wellington, Kelburn
05.7 … Wellington Aero
30.9 … Christchurch Gardens
32.3 … Christchurch Aero
07.2 … Dunedin, Musselburgh
19.7 … Dunedin Aero
27.8 … Queenstown Gardens
15.7 … Queenstown Aero
01.4 … Greymouth Aero

[spwill]

For the Auckland region I'm picking Henderson would have the most days over 25C ? lessening sea breeze affect there.
The Tauranga number seems a bit low, Tauranga average max is 24C for Jan and Feb.

Metservice shows kerikeri has had 24 days with a maximum of 25C or higher in the last 30 days, lowest maximum in that period is 23C.

[drcam]

Auckland currently gets 21 "hot days" of 25 degrees or over per annum, Hamilton gets 26, Wellington gets three, Christchurch 31.

Hobart, Tasmania gets 18 hot days a year; Launceston gets 30, while Devonport on the north coast of Tasmania gets ten. It always seems warmer here than in New Zealand though.

[drcam]

Also, Melbourne in Victoria which is on the same latitude (within a couple of miles) as Hamilton, gets on average twenty-nine days a year with the maximum temperature above THIRTY. Move here and eat more ice cream!

[wembley]

Thanks for the info, Nev. There's a massive gap in hot days between Musselburgh and Dunedin Airport

[RWood]

Thanks for the info, Nev. There's a massive gap in hot days between Musselburgh and Dunedin Airport

That is offset by much warmer nights at Musselburgh. Its annual Tmean is higher than at the airport.

[Captain Salty]

What accounts for the difference between Queenstown Gardens and Aero?

[NZstorm]

It always seems warmer here than in New Zealand though.

The North Island is warmer than Tasmania. Tasmania fits in with the top of the South Island for temperature means.

[Nev]

For the Auckland region I'm picking Henderson would have the most days over 25C ? lessening sea breeze affect there.

Yes, NIWA's longterm 'Henderson North' site (formally known as 'Henderson Riverpark') shows a whopping 57.2 days-per-year over 25C. Note, however, that this is a small urban backyard site, described as having 'not the best of exposures, but representative of the area'.
Inland Admore Aero to the SE has about 37.9 days-per-year.

[Nev]

What accounts for the difference between Queenstown Gardens and Aero?

Queenstown Gardens is near the lake foreshore and both its T-mins and T-maxs are roughly about a degree warmer than the airport, which is about 6km east in more inland Frankton. Probably makes all the difference when struggling to get past 25.0C.

[tgsnoopy]

The Tauranga number seems a bit low, Tauranga average max is 24C for Jan and Feb.

Metservice frustrates many in Tauranga by using the exposed site at the Airport which in no way represents the temperatures experienced by the general population here

[Manukau heads obs]

Yesterday was one of the first days since december that was above average temperature here

[midgrove]

I have never understood the bragging about high temperatures, anything over about 28 is just plain uncomfortable.
During my time working at Metservice there were always complaints that the TV temperatures were too cold, because someone can always get a higher reading from a poorly exposed site. Here in Blenheim the temperatures are recorded at Woodbourne airport which being further inland usually records higher temps than in town, but people still complain the TV temps are too cold!

[RWood]

I have never understood the bragging about high temperatures, anything over about 28 is just plain uncomfortable.
During my time working at Metservice there were always complaints that the TV temperatures were too cold, because someone can always get a higher reading from a poorly exposed site. Here in Blenheim the temperatures are recorded at Woodbourne airport which being further inland usually records higher temps than in town, but people still complain the TV temps are too cold!

The obsession with getting high Tmaxs is silly. Blenheimites would be better off focusing on their excellent sunshine stats. Wellington gets an even worse press than it deserves because of its smallish diurnal range - the flipside of that is that I always notice the coolness of the nights at most locations south of Auckland city.

[treetop]

Its interesting that although the northwest around Auckland and Northland has the highest average temperatures, they would have 25 deg on only 6 months[nov-april] While Gisbourne down to Alexandra may have 25 on 9 months [sept- may.] Wangarei being the exeption as there is often a slight fohn effect of wind crossing Northland,

[Richard]

Alexandra may have 25 on 9 months [sept- may.] ,

This summer would have pushed down the averages a bit, has Alexandra even been over 30 this summer yet?

[treetop]

I think one day. Wine growers must be a bit worried,realy need some sunshine/heat to finish off.

[Nev]

Came across this EHINZ 2014 animation based on NIWA data…

Each territorial authority was assigned one monitoring station inside it or most appropriate station outside the region. An exception was Auckland which was given 3 station to better approximate the climatic conditions for the larger population. A monitoring station was chosen based on being closest to the population weighted centroid of the territorial authority.

[tunster]

It always seems warmer here than in New Zealand though.

The North Island is warmer than Tasmania. Tasmania fits in with the top of the South Island for temperature means.

Launceston does seem very similar to Nelson in sunshine hours and temperatures (Nelson slightly warmer on average). But Nelson gets a fair bit more rain, naturally, being exposed to the north.

[drcam]

Was in Launceston last week.

Launceston gets a lot more very hot days (eg. 31-32 degrees) than Nelson, it also gets more diurnal range being inland; when I was there, it got down to 5 degrees that night. I think that the climate there is more reminiscent of the Wairarapa, or perhaps Blenheim.

The scenery and food there are lovely, just no paua fritters

[Willoughby]

Also, Melbourne in Victoria which is on the same latitude (within a couple of miles) as Hamilton, gets on average twenty-nine days a year with the maximum temperature above THIRTY. Move here and eat more ice cream!

Also considerably cooler in summer when Melbourne has southerly-half winds. Hamilton has fairly stable summers with max temps normally in a narrow band (22-27C).