Weather Eye with John Maunder

Monthly rainfalls for Tauranga have been recorded at several recording sites during the last 124 years.

From January 1898 to December 1904, the observation site was described as the Tauranga Harbour, from November 1904 to April 1907 the site was described as simply ‘Tauranga'.From January 1910 to December 1923 the site was Waikareao, in Otumoetai; from January 1924 to September 1940 the site was at 148 Waihi Rd, in Judea; from October 1940 to January 1941 the site was at Te Puna; and from February 1941 to now, the site is Tauranga Airport.

The methodology use in adjusting the older sites to the current observing site is published in the ‘NZ Meteorological Service Miscellaneous Publication' No 180 in 1984.

It is considered that the homogeneous rainfall series described here is a fair and true record of what the rainfall would have been if the current observation site (Tauranga Airport) had been used since 1898.

This should be coupled with the understanding that although standard accepted methodologies have been used, any adjustments are only estimates of what would have occurred if the location of the rainfall records had always been in the same place with the same surroundings and the same or similar recording gauge.

In terms of climate change (such as is it getting wetter or drier, or warmer or colder), the methodology used in computing an ‘official' set of climate observations is very important, as otherwise erroneous conclusions may be drawn.

The graph shows the range of rainfalls from an extreme high of 381 mm in 1925 to a low of 19 mm in 1906.

The rainfall in June 2022 was 256 mm, the seventh wettest June in 124 years of observations.

Since 1898, there have been 19 June months with a rainfall of 200 mm or more, and 11 June months with rainfalls of 50 mm or less.

In chronological order the wettest 18 June months are: 1915, 1917, 1920, 1925, 1930, 1935, 1939, 1943, 1946, 1961, 1968, 1971, 1981, 1985, 1997, 2010, 2014, 2020 and 2022.

By contrast the driest June months in chronological order are: 1906, 1913, 1914, 1933, 1942, 1958, 1959, 1967, 2001, 2012, and 2015.

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Tauranga June Average Afternoon Temperatures 1913-2022

Temperatures have been recorded in the Tauranga area at several sites during the last 107 years, including at the current Tauranga Airport site from June 1990.

The graph shows details of the average daily maximum temperatures, called simply ‘afternoon', for Tauranga for June from 1913-2022.

The long-term average afternoon temperature in June for Tauranga is 14.8 degrees Celsius.

The cool' June months were in 1972 with 13.0 degrees Celsius, 1936 with 13.2 degrees Celsius, and 1933 with 13.3 degrees Celsius.

The ‘warm' June months were in 2014 with 16.9 degrees Celsius, 16.8 in 2021,1916 and 2011, both with 16.6 degrees Celsius, and June 2016 and June 2022 with 16.5 degrees C.

June 2014 had an average afternoon temperature of 16.9 degrees Celsius was the warmest June on record since observations were first made in 1913.

The graph of the average afternoon temperatures for June shows generally ‘normal' variations from June to June during the last 100 years.

But many of the last 20 June months since 1996 have been a little ‘warmer' than other June months since 1913.

From 1913 to 2022, there have been 17 June months with an average afternoon temperature of 15.6 degrees Celsius or more, and 12 June months with an average afternoon temperature of less than 13.9 degrees Celsius.

The ninth ‘warmest' June months on record, in chronological order, are: 1916, 1971, 1981, 1998, 1999, 2002, 2003, 2011, 2014, and 2016.

By contrast, the seventh ‘coolest' June months on record, in chronological order, are 1933, 1936, 1941, 1944,1969, 1972 and 1976.

The average afternoon temperature in June during the 51 year period 1914-1964 was 14.7 degrees Celsius, compared with 14.9 degrees Celsius for the 51 year period from 1965 to 2015.

For further information on a range of weather/climate matters see my recent book "Fifteen shades of climate" (Amazon)