The combination of northwesterly winds and the foehn effect
which hit the South Island at the start of August combined to
produce record-breaking temperatures, Niwa says.
In its August climate summary, Niwa details how the warm
weather hit at the end of July and continued into the first
few days of August.
As a result, 13 locations around New Zealand recorded their
warmest August daily maximum temperature on the first day of
the month, including Dunedin (21.7degC) and Balclutha
Queenstown recorded its second-highest temperature of
18.9degC, Ranfurly its second-highest (18.4degC) and
Alexandra its fourth-highest (20.3degC).
The conditions also meant 37 places around New Zealand
recorded their warmest minimum temperature, including
The second-highest minimum temperature was recorded by
Dunedin (13.3degC) and Lauder (12.2degC) and the equal
second-highest by Wanaka (9.4degC), Alexandra (11.6degC) and
Nugget Point (10.5degC).
Along with the warm conditions came strong winds. Record
gusts were recorded at Tara Hills (98kmh), Wanaka (93kmh) and
equal fourth-highest in Queenstown (85kmh).
By contrast, Middlemarch recorded the lowest temperature of
the month, -7degC on August 4.
The climate statistics for New Zealand's six main centres
showed Auckland to be the warmest, wettest and cloudiest,
Christchurch the coolest and driest and Tauranga the
Dunedin failed to rate, even though its rainfall was only 76%
of normal at 43mm and its mean temperature was -0.2degC lower
than normal at 7.6degC.
The foehn effect happens when moist air flows up and over a
hill or mountain, creating higher temperatures as it descends
on the downwind side.