Was Winter 2022 Wet and Cold?

With winter apparently ending on September 1 (try telling that to nature), I thought it might be instructive to consider how wet and cold we’ve really been, given that memory is a tricky thing. At times it’s seemed to be very wet indeed, but has it been all that bad? Well, yes. The information shown below comes from two parts of the North Island – Manawatu (rainfall) and Tauranga (temperature).

Rainfall figures for Manawatu, 2022 in blue. Graphic: Lee Simpson

This graphic was prepared to demonstrate to a business that buys fresh produce why growers in New Zealand have been finding it so difficult this year so far, and this winter in particular. The rainfall pattern has been all over the place, only hitting the average in March and staying well above average almost all winter. Having 61 years of rainfall data collected on a farm near Sanson means there’s a well-established long-term average.

My own attempt at gathering temperature data isn’t quite so flash, but is included for what it’s worth. The information comes from a wireless digital maximum-minimum thermometer kept in an orchid shadehouse in central Tauranga. The shadehouse has a roof but is open at the sides. The day-to-day and night-to-night changes are interesting from a plant-grower’s point of view.

The table covers the period June 1-August 15 for each year (so misses the 2022 ‘atmospheric river’ from the tropics that arrived later in the week starting August 15).

Coldest Day11.7C          
June 29
July 10 & 11
July 2 & 9
Warmest Day20.5C           
June 1
July 22 & Aug 11
Aug 12
Coldest Night1.5C             
Aug 12
June 29
July 9 & 10
Warmest Night13.6C           
July 8
June 8
June 20
Max. Day to Day Drop18.6 – 13.5C
July 13-14
20.1 – 14.3C
July 24-25
18.4 – 13.1C
July 21-22
Max. Night to Night Drop11.1 – 4.8C                
July 28-29
8.6 – 1.0C
June 28-29
9.6 – 1.3C      
July 7-8
Max. Day to Day Rise11.9 – 17.1C                  
Aug 9-10
12.8 – 19.1C
Aug 5-6
13.7 – 18.4C 
 Aug 6-7
Max. Night to Night Rise4.8 – 12.6C                
July 18-19
3.0 – 12.3C
July 16-17
3.8 – 11.3C
July 12-13