Feature article

Winter rainfall at Whangarei Airport

Exceptionally high rainfall in July 2007 that contributed most to the winter total, after a relatively dry period in the preceding months.

3–month rainfall totals for Whangarei Airport.

Winter temperatures were higher than normal as expected over much of the North Island, but unexpectedly low in the south of New Zealand. The outlook for normal to above normal rainfall in the north of the country also proved accurate (see the outcome map).

This year Whangarei Airport recorded its highest winter (June–August, JJA) rainfall (724 mm) since 1973, when 743 mm was measured. The average winter rainfall at Whangarei is 456 mm. The figure right highlights the exceptionally high rainfall in July 2007 that contributed most to the winter total, after a relatively dry period in the preceding months.

The figure to the right compares 3–month rainfall totals for Whangarei Airport, arranged in rows by July to June year and in columns, from 1972–73 to the present. The columns are arranged from left to right as total rain for May–July (MJJ) to April–June (AMJ). The colour coding categorises the decile ranges of the observed 3–month rainfalls in each column respectively.

The magenta segment in the JJA column marks the 1973 winter rainfall total noted above. The current winter rainfall (dark blue segment) occurs in the top decile for JJA. The driest winter in the record was 2004, shown in brown. April to June rainfall for 2007, also noted above, was the lowest rainfall for that period in the record.

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Note: The data displayed here are from a composite of stations and should not be taken as final. White segments in the right hand figure indicate missing or as yet unrecorded data.