Covering period of Wednesday 20th – Friday 22nd September – MetService is forecasting a significant snow event for inland areas of both Canterbury and northern Otago Thursday night and throughout Friday. Accumulations of around 10cm above 200 metres, and 20-40cm for areas above 400 metres are expected.
This will be unwelcome news for farmers in the middle of the lambing and calving seasons and anyone travelling in these areas.
MetService Meteorologist Clare O’Connor states: “We’re not just looking at alpine areas of the South Island/Te Waipounamu – the snow level could be as low as 300 metres in Otago, and down to 200 metres over the Canterbury Plains. This is a significant event, and particularly impactful for the rural community given the time of the year.”
Temperatures will plummet in line with this event, and will be particularly noticeable because of the balmy temperatures today in the east of the South Island. In South Canterbury, Fairlie hit 25°C midday Wednesday but can only expect to reach 10°C on Friday. Similarly, Alexandra saw 24°C, but a daytime high of 11°C on Friday and just 2°C overnight into Saturday.
“These colder temperatures will cause the snow to stick around, and travel disruptions are expected in the alpine passes not only during the event but for the days following also.” O’Connor details.
MetService forecasters are monitoring the situation closely, but there is still some uncertainty regarding snow amounts and levels. Further information, including any watches or warnings for this event, will be issued this evening and Thursday morning. People are advised to keep up to date with the latest forecasts.
This significant snow follows already adverse conditions. Severe Weather Watches and Warnings for heavy rain accumulations and strong winds are currently in place across the South Island/Te Waipounamu for today and Thursday. Severe gale northwesterlies, with gusts of up to 140km/h are forecast in the Canterbury High Country and rainfall accumulations of 300-450mm in the Westland ranges.
For media enquiries or to arrange an interview with one of our meteorologists please call 04 4700 848 or email metcomms@metservice.com
Understanding MetService Severe Weather Warning System
Severe Thunderstorm Warnings (Localised Red Warning) – take cover now:
This warning is a red warning for a localised area.
When extremely severe weather is occurring or will do within the hour.
Severe thunderstorms have the ability to have significant impacts for an area indicated in the warning.
In the event of a Severe Thunderstorm Red Warning: Act now!
Red Warnings are about taking immediate action:
When extremely severe weather is imminent or is occurring
Issued when an event is expected to be among the worst that we get – it will have significant impact and it is possible that a lot of people will be affected
In the event of a Red Warning: Act now!
Orange Warnings are about taking action:
When severe weather is imminent or is occurring
Typically issued 1 – 3 days in advance of potential severe weather
In the event of an Orange Warning: Take action.
Thunderstorm Watch means thunderstorms are possible, be alert and consider action
Show the area that thunderstorms are most likely to occur during the validity period.
Although thunderstorms are often localised, the whole area is on watch as it is difficult to know exactly where the severe thunderstorm will occur within the mapped area.
During a thunderstorm Watch: Stay alert and take action if necessary.
Watches are about being alert:
When severe weather is possible, but not sufficiently imminent or certain for a warning to be issued
Typically issued 1 – 3 days in advance of potential severe weather.
During a Watch: Stay alert
Outlooks are about looking ahead:
To provide advanced information on possible future Watches and/or Warnings
Issued routinely once or twice a day
Recommendation: Plan
