Metservice have issued a severe weather watch with a warning for rapidly rising streams and rivers as well as slips and surface flooding.
The heaviest rain is likely around the Northwest Nelson Ranges, with 90 to 130mm of rain expected tonight between midnight and 3pm tomorrow. Peak intensities of 10 to 15mm per hour can be expected Wednesday morning.
A frontal system over the Tasman Sea is expected to move slowly east over New Zealand during Wednesday and Thursday.
