Kapiti was drenched by more rain overnight Monday than it usually gets in a month.
Firefighters responded to 28 calls as the rain caused flooding throughout Waikanae, Paraparaumu and Paekakariki.
''From 8pm we were non-stop until about 11.15pm, which would have been our last call,'' said Paraparaumu station officer John Arthur.
''The calls were piling up, and if it wasn't life threatening, it was just added to the list.''
Mr Arthur said 26 of the 28 calls were for flooding and another was an alarm activation.
Many garages needed water pumped out, some of the worst having up to 16 centimetres of water in them, he said.
Rainbow Ct in Raumati South was knee-deep in water, he said.
After a long run of fine weather, Mr Arthur said leaves and debris can build up and block drains in heavy rain.
''That's probably what happened. Our drainage system really didn't cope too well, which caused plenty of issues. If you don't give them a good clean, this can easily happen.''
MetService meteorologist Daniel Corbett said it often comes as a ''shock to the system'' when active weather hits after a spell of settled weather.
''We had that big high that lasted for a week, 10 days, that moved away - we got into a northerly and that fed in some subtropical moisture from north of New Zealand.''
He said the moisture added ''fuel'' to the storms, with two rain bands moving across the North Island from the west.
''We had the first splurge in the morning and then we got the main deluge through the late afternoon and into a good part of the night.''
Kapiti Coast Airport recorded 57 millimetres of rain in the 24 hours to midday Tuesday, and Waikanae water treatment plant recorded 63mm for the same period, he said.
Higher ground in the Tararua Range was hit by more than 100mm in the 24 hours.
Mr Corbett said typically, the Paraparaumu airport site would get 48.5mm for the entire month of February.
The rain peaked between 8pm and 9pm in Kapiti before a southerly change arrived at about midnight, bringing cooler weather and showers.
He said Kapiti could expect a high to remain through to the weekend with lower humidity and temperatures in the 20s.
- Kapiti Observer
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