Marlborough is heading for a record dry year.
The region's district council says 30 millimetres of rain is needed before the end of this month or 2015 will become the driest on record in Blenheim.
It says small amounts of rain in recent days haven't changed the dry outlook heading into summer, but were enough to delay the immediate onset of water restrictions.
The previous lowest annual rainfall recorded in Blenheim since records began in 1930 was in 1969, when 398 millimetres fell.