A cold front clears off to the northeast of the North Island on Monday morning leaving a cool west to southwesterly airflow over the country during the day. A trough then hits the lower South Island later in the evening bringing even colder air and some very unsettled weather.
For the western North Island (including Bay Of Plenty) expect morning rain to ease to showers, heavy at times with a risk of hail. Winds will be fresh from the west then tending southwest by evening. Snow lowers about the Central Plateau to 500m in the evening. Along the east coast morning cloud may bring a spot of rain then becoming mostly sunny in the afternoon as northwest winds tend westerly. Temperatures along the east coast reaching into the mid teens.
For the West Coast of the South Island early rain eases to showers, snow lowers in the mountains to 400m. Winds from the southwest. Parts of South Westland may become fairly dry during the morning then showers increase again overnight. Mostly sunny weather in the east with northwesterly winds (possibly gusty in the morning about North Canterbury and Marlborough) then a southwest flick develops in the afternoon about Canterbury which may bring a few showers, showers clear in the evening.
For Southland expect showers all day long, some may be heavy at times with a risk of hail. Some snow also down to 300m although snow may drift 100 to 200m lower now and then. Otago has cloudy areas, a shower or two possible at times but long dry spells also. In the evening a very strong southwest change moves into Southland with a risk of gales (gales likely near the coast), this southwest change hits Otago overnight.
Image: Monday 25th June 2018 3:00pm MSLP / Rain map – weathermap.co.nz