Weather: Heavy snow watch and rain forecast

Heavy snow is forecast for the Southern Lakes District mountains from 9.00 am Monday morning with a chance the snowfall could be down to 300 metres.

Met service issued the following weather watch for the district Sunday (July 28th) morning:

"Periods of heavy snow above 800 metres developing during Monday morning, where snowfall amounts may approach warning criteria.

"Note, snow level is expected to lower to 300 to 500 metres overnight Monday and during Tuesday morning with significant accumulations shifting towards eastern Otago. Moderate chance of upgrading to a Warning."

Temperatures are forecast to continue dropping from yesterday's relatively mild 12 degrees to a high of 7 degrees and a low of 2 degrees.

The national forecast indicates that the cold conditions could carry through to Wednesday:

"An active trough in the Tasman Sea is forecast to spread across southern and central New Zealand, bringing rain to many areas.

"There is low to moderate confidence of warning amounts of rain for Southland, South Canterbury from the foothills to the coast, Westland (mostly in the ranges), Buller, Tasman, northern Marlborough, and Mount Taranaki. However, the confidence in warning amounts of rain for Eastern Otago is now considered high.

"In addition, there is moderate confidence of warning accumulations of snow above about 500 metres for eastern Fiordland, and inland areas of Southland and Otago.

"For the southern Canterbury High Country the confidence in heavy snow is low. Finally, a strong easterly flow is forecast for the southwest of the South Island later in the day, and there is moderate confidence of easterly gales becoming severe in exposed parts of Fiordland and south Westland."

Tuesday 30 July

"The active trough is expected to move northwards bringing a period of rain to most places. There is moderate confidence of warning amounts of rain for Mount Taranaki and low confidence for the eastern ranges of Bay of Plenty. There is also low confidence of northerly winds reaching severe gale about exposed parts of South Taranaki across to Taihape.

"Southeasterly rain is forecast for the southeast of the South Island.

"There is low confidence of warning amounts of rain for Southland and South Canterbury, but high confidence for eastern Otago. The is moderate confidence of warning amounts of snow above about 500 metres for inland areas from eastern Fiordland through Southland and Otago. Confidence for warning amounts of snow in the southern Canterbury High Country is low.

"Strong easterlies continue about the southwest of the South Island, and there is moderate confidence of easterly gales becoming severe in exposed parts of Fiordland and Westland.

"People are advised to keep up to date with the latest forecasts."