Mainly fine weather was felt across the nation to kick off the school holidays, but as we near midweek, MetService is forecasting heavy rain and strong winds to put an end to the sunny spree.

On Monday, settled weather was widespread nationwide thanks to high pressure that moved in during the weekend. 

However, today (Tuesday) more clouds will be seen across the skies; northeasterly winds will pick up and some rain will fall around the country's southwest.

MetService meteorologist Lewis Ferris warns Wednesday and Thursday are the main risk period for severe weather. 

“Heavy Rain Watches are already in force for western and northern parts of the South Island. It’s likely some of these will be upgraded to Orange Warnings and areas in the North Island may be added,” he says.

This potentially severe weather is brought about by a low pressure system approaching from the Tasman Sea which drags some warm and humid air across our shores.

While this does mean some warmer than average temperatures it also increases the chance of heavy rain as the system passes over. Strong northeasterly winds will also be seen before the rain arrives.

While most of the North Island will be covered by the warm and humid air, there is some cold air being dragged across the southern half of the South Island. 

This means Thursday brings the risk of snow falling down to around 500 metres for inland Otago and southern parts of Canterbury. Prolonged rain is also possible around these areas and severe weather forecasts might be issued.

While coastal North Otago looks likely to escape the worst of the weather, the drop in temperatures over the next couple of days will be noticeable, with a high of 11 degrees predicted for Thursday, and rain forecast for the next two days.

Lewis says It’s a good idea to stay up to date with the latest forecasts this week as the weather from Wednesday will be very different to now and severe weather may impact numerous regions.