Nelson Tasman Civil Defence Emergency Management Heavy Rain Warning

Tuesday 13 December 2011

Latest Information

Heavy Rain Expected

An active front over the Tasman Sea should move slowly eastwards across New Zealand during Wednesday and Thursday bringing with it very heavy falls of rain for much of the country, with the heaviest falls in the west and north of both islands.

Metservice has forecast the rain to arrive late Tuesday evening and continue until early Thursday for Westland and Buller and for the northwest ranges of Nelson where as much as 280mm of rain may fall.

While the rain in all these areas should gradually ease during Thursday morning people are advised rivers and streams may rise rapidly, surface flooding and slips are possible.

The forecasted intensities of 20 to 30mm per hour are expected to be delivered from late Wednesday morning through to Wednesday evening in the hills west of Motueka.

Throughout the rest of the Nelson Tasman region rain should become persistent and heavy overnight from midnight Tuesday. In the 30 hours from midnight Tuesday to 6am Thursday 150 to 200mm of rain is expected to fall. Peak intensities of 15 to 25mm per hour during this time are expected from Wednesday evening and until Thursday morning.

Potential for flooding

Civil Defence advises that because the heavy rain warning covers a wide area and extends well into Thursday there is potential for some flooding.

  • People close to rivers and streams should prepare for a rapid rise in water levels.
  • Farmers should move stock to high ground where necessary.
  • Drivers should exercise caution as high winds are expected as part of this severe weather band.

For further information contact Roger Ball, Nelson Tasman Emergency Management Office, phone 027 246 8857.