General September Weather

[cbm]

That's unreal.

I noticed I'm well over 900mm for the year to date now. This is after being 200mm at 10th May. We have certainly caught back up to where we should be. It could end up being that we actually achieve our 1200mm average which we very rarely seem to be able to achieve in the past decade.

Niwa's rainfall map. Looks like average drops off quite quickly depending how close to the Hakarimatas you are within the Horsham downs area.

waikato_rainfall.JPG

[RWood]

Ghastly sunshine numbers for Kelburn. 79.6 hours is 25 less than the previous record September low, barely more than the record August low, and a little under 49% of the LTA for the month - previously no month had recorded less than about 53% of its mean. The % of the recordable amount was just under 24, equal with May 1942 which at least had the excuse of being easily the wettest May on record. If I had seen such a number for a month in the times when summaries were published in the NZ Gazette I would initially have thought there had been a misprint. I certainly rate this as by far the most unpleasant September I have experienced here. It reminds me that even in my prime I wouldn't have ever considered living in one of the world's seriously cloudy climates, regardless of job and salary.

[Nev]

September 2016 was another fairly warm overall. Quite wet in the latter half for some areas of the North Island though. Cloudy for the North Island and eastern parts of the South Island, but fairly sunny for the rest of the South Island.

Sep 2016 Climate Anomaly Map ℅ NIWA.gif

Some very preliminary September 2016 figures for the main centres:

Code: Select all

September 2016 Average Temps, Rainfall and departures from their 1981-2010 normals ℅ NIWA

Site                      T-max °C       T-min °C       T-mean °C    Rainfall mm

Auckland, Mangere        17.2  +0.9     10.9  +1.3     14.0  +1.0     174  169% 
Auckland Aero            16.9  +0.5     10.8  +1.1     13.8  +0.8     175  194% 
Tauranga Aero            16.7  +0.1     10.2  +1.9     13.5  +1.1     166  197%
Hamilton Aero            16.5  +0.2      8.7  +2.5     12.6  +1.3     144  143% 
Hamilton, Ruakura        16.8  +0.4      9.0  +2.3     12.9  +1.4     114  124% 
Wellington, Kelburn      13.3  -0.4      8.8  +0.9     11.0  +0.2     134  136% 
Christchurch Aero        14.3  -0.5      6.2  +2.3     10.3  +0.9      37   92% 
Dunedin, Musselburgh      n/a   n/a      n/a   n/a      n/a   n/a      24   49%
Greymouth Aero           14.3  +0.2      7.2  +0.6     10.8  +0.5     174  131%

[David]

September was the wettest month of the year here to date. Some stats from my station

Total rainfall = 172mm (only 36mm in the first half, 136mm in second half)
Avg temp = 13.4
Avg daily high = 17.3
Avg daily low = 10.2
Highest temp = 20.1 on 29th
Lowest temp = 3.0 on 11th

[Richard]

September rainfall total 20.0 mm

Highest temp 20.2 - 17th
Lowest temp -3.4 - 11th

[NZ Thunderstorm Soc]

September rainfall total 42.2mm

Highest temp 20.8C - 2nd ( I bet Riccarton got to 30C !)
Lowest temp -1.7C - 10th

[Nev]

Yes, no doubt Riccarton will take top place again with 25.0C, compared to 22.0C at Chch Aero. Kaikoura Aero also recorded around 25C on the 16th, but NIWA only record Kaikoura Peninsular, which reached 23.2C on the same day. Hastings wasn't far behind with 23.1C on the 2nd.

[Nev]

Here's NIWA's preliminary, 'Semptember 2016 National Climate Summary'.

A wet month for the North Island, dry for the South Island, and warm almost everywhere.


The national average temp of 11.0C was 0.43C above normal.

The month's highest temp of 25.0C was again recorded at NIWA's questionable Riccarton, Christchurch site on the 2nd, and the lowest temp of -6.1C was again recorded at Mt Cook Aero on the 9th.

[spwill]

Cloudiness was the feature of the month for NZ and cool maximums for eastern areas.

[einzack]

Cloudiness was indeed the story of the 2nd half of the month for the eastern side of the country.
I had a look at the Oamaru data which showed that for the period 1-17th, average sun hrs per day was 6.3hrs per day. From the 18th through to yesterday, the average was a paltry 2.3hrs per day, with 5.4 hours the most recorded on any single day. I'm actually surprised the number is that high for the 2nd half. I'm not saying that's a record (haven't checked at all), but it felt damn miserable, especially compared to the first half.....

[RWood]

Cloudiness was indeed the story of the 2nd half of the month for the eastern side of the country.
I had a look at the Oamaru data which showed that for the period 1-17th, average sun hrs per day was 6.3hrs per day. From the 18th through to yesterday, the average was a paltry 2.3hrs per day, with 5.4 hours the most recorded on any single day. I'm actually surprised the number is that high for the 2nd half. I'm not saying that's a record (haven't checked at all), but it felt damn miserable, especially compared to the first half.....

You won't be able to do satisfactory comparisons because the Oamaru Ews data has only a few months of history and the older sites in the region were manual and bound to have lower readings in the same conditions. For what it's worth the homestead site used from 1929 to 1953 - don't have my home computer data in front of me to name it - recorded only 85 hours in December 1937 (82 at Waimate). The period December 1937 to April 1938 was very cloudy for Canterbury (Mackenzie excluded) and eastern Otago.

[RWood]

The site was Kauru, Balruddery.

[Nev]

Thought these September anomaly maps in two halves might be of interest…

Sep 2016 Climate Anomaly half-maps ℅ NIWA.gif