General May Weather

[David]

Nev, according to your stats posted above Akl Aero was 0.2 degrees below average, so how can it possibly be the second warmest May?

[Nev]

Nev, according to your stats posted above Akl Aero was 0.2 degrees below average, so how can it possibly be the second warmest May?

Sorry, I mean't its 2nd warmest 'daily' May temp. Have amended that statement to make it clearer.

[David]

Nev, according to your stats posted above Akl Aero was 0.2 degrees below average, so how can it possibly be the second warmest May?

Sorry, I mean't its 2nd warmest 'daily' May temp. Have amended that statement to make it cleaer.

Ah right, you are referring to that 24C day at the airport. Had forgotten about that.

Do you have a rain total for Waiheke? I recorded 154.6mm for Howick, so it was quite a wet month overall.

[Nev]

Do you have a rain total for Waiheke? I recorded 154.6mm for Howick, so it was quite a wet month overall.

No, I've missed a some readings, but there's a professinal WS not far from here that publishes on Thursday. Will let you know.

[Nev]

Thought this brief May Summary snipped from MetService's June 2015 Outlook might be of interest...

May - a month of extremes - MetService

May saw frequent Lows over the Tasman Sea and New Zealand, with more northwesterlies over the country. Extremes of both rainfall and temperature featured in May. The first half of the month was unseasonably mild, with heavy rain frequenting western regions. A deluge of rain affected the Kapiti Coast and Wellington on 14 May, with major flooding leading to loss of life and grinding transport links to a halt. Paraparaumu experienced its wettest May on record (252mm), following on from its wettest April ever. In contrast, it was a very dry May for Canterbury and Marlborough, and drier than usual for the eastern North Island. Notably, only 2.8mm fell in Timaru (the fourth driest month on record there), and Oamaru received just 8.8mm. The second half of the month was cold, with heavy snow affecting the lower South Island on 25 May. Snow also fell on the Central Plateau, with a flurry in Napier too. After the snow, a ridge of high pressure moved in, bringing a period of hard frosts for inland areas of both Islands.

These rainfall, temp and sunshine anomaly maps from NIWA also show just how extreme the 2 halves of the month in most parts actually were (first half on left and last half on right)…

May 2015 Climate Anomaly Maps in 2 halves ℅ NIWA.gif

[NZ Thunderstorm Soc]

Readings from my station for the month:

Ave temp 9.3°C
Ave Minimum 2.8°C
Ave Maximum 15.7°C
Minimum -5.9°C on 29th
Maximum 24.7°C on 6th
Rainfall 15.9mm, YTD 198.8mm

[Richard]

I must start keeping records myself but ive just worked out the last 12months rainfall for Culverden, 321mm,would this be the lowest 12 month period in NZ?

[RWood]

I must start keeping records myself but ive just worked out the last 12months rainfall for Culverden, 321mm,would this be the lowest 12 month period in NZ?

That's almost the Alexandra average. Lowest 12-month total for NZ was recorded there in Nov 1963-Oct 1964, at 167mm (6.59" in the measurements of the day).

[Nev]

Do you have a rain total for Waiheke? I recorded 154.6mm for Howick, so it was quite a wet month overall.

No, I've missed a some readings, but there's a professinal WS not far from here that publishes on Thursday. Will let you know.

Weatherwise's Waiheke site recorded 133.0mm for this May.

[Nev]

Here's NIWA's preliminary, 'May 2015 National Climate Summary'.

Dry and sunny for eastern parts of the country.


The national average temp of 11.2C was 0.4C above normal.

The month's highest temps were 27.0C at Waiau School, 26.8C at Rangiora and 26.7C at Riccarton (Christchurch) on the 6th.

NIWA's Riccarton site also recorded its 2nd highest average mean-temp (based on nearby Christchurch Garden figures going back over 100 years).

The lowest temp of -9.0C was again recorded at Hanmer Forest on the 28th, followed by -8.6C at Pukaki Aero and -8.1C at Ranfurly both on the 29th.

Blenheim and Cheviot observed their sunniest May on record.

[RWood]

Here's NIWA's preliminary, 'May 2015 National Climate Summary'.

Dry and sunny for eastern parts of the country.


The national average temp of 11.2C was 0.4C above normal.

The month's highest temps were 27.0C at Waiau School, 26.8C at Rangiora and 26.7C at Riccarton (Christchurch) on the 6th.

NIWA's Riccarton site also recorded its 2nd highest average mean-temp (based on nearby Christchurch Garden figures going back over 100 years).

The lowest temp of -9.0C was again recorded at Hanmer Forest on the 28th, followed by -8.6C at Pukaki Aero and -8.1C at Ranfurly both on the 29th.

Blenheim and Cheviot observed their sunniest May on record.

Blenheim's 214 sunshine hours for May has rarely been exceeded, but in 1930 & 1931 both Nelson and Blenheim (older sites) reached or exceeded 220 hrs - Nelson 223.4 (1931), Nelson 222.0 (1930), Blenheim 220.2 (1930), Blenheim 219.6 (1931). The period Feb-July 1930 had persistent above average MSLPs in central NZ, with Nelson getting 1336 hours of sun in that time.

[Richard]

I must start keeping records myself but ive just worked out the last 12months rainfall for Culverden, 321mm,would this be the lowest 12 month period in NZ?

That's almost the Alexandra average. Lowest 12-month total for NZ was recorded there in Nov 1963-Oct 1964, at 167mm (6.59" in the measurements of the day).

Thanks for that info Rupert,interesting.
Sorry i should have been clearer,for that period (31/5/14 to1/6/15) was that the lowest in NZ