MetService: A Foggy Day
18 January 2016
Wellington city residents were finding it hard to see yesterday, as a bank of fog gradually rolled in off the sea on
Sunday afternoon. “This fog was caused by a northeasterly flow bringing very warm, humid air down from the north,” said
MetService Meteorologist Claire Flynn. “As the warm air moves across a cooler sea surface, it causes the moisture in the
air to condense into fog. A southerly sea breeze then pushed the fog into Wellington.”
While fog may have affected flights into and out of Wellington yesterday, the weather moving onto New Zealand today is
expected to have wider-reaching effects.
An active front moves onto the country today, followed by a low pressure system which crosses New Zealand on Tuesday.
Severe Weather Warnings and Watches have been issued for heavy rainfall affecting a number of areas in the north and
west of both islands. Included with this heavy rain is the possibility of thunderstorms and downpours for some western
areas. There is a high risk of thunderstorms for northwestern areas of the North Island and for northwest Nelson this
evening, while the heaviest downpours (25 to 40mm/hr) are possible for the Waitomo, Taranaki and Nelson regions.
Rain is also forecast to spread into eastern areas of the South Island, which will be welcome news for many farmers. On
Tuesday the rain should turn to showers as the low pressure system crosses the country, though some of these showers
could still be heavy with a risk of thunder.Wednesday and Thursday see a return to more settled weather, as a
northwesterly flow establishes itself over the South Island and high pressure builds over the North Island.
Severe Weather Watches and Warnings are reviewed and re-issued atleast every twelve hours, and more often if necessary.
To get the most up to date information on the severe weather around the country, or any other forecasts, see metservice.com or on mobile devices at m.metservice.com. You can also follow our updates on MetService TV, at MetService New Zealand on Facebook, @metservice and @MetServiceWARN on Twitter and at blog.metservice.com
MetService issues Warnings, Watches and Outlooks for severe weather over New Zealand.
Warnings are about taking action when severe weather is imminent or is occurring. They are issued only when required.
Recommendation: ACT
Watches are about being alert when severe weather is possible, but not sufficiently imminent or certain for a Warning to be
issued. They are issued only when required.
Recommendation: BE READY
Outlooks are about looking ahead, providing advance information on possible future Watches and/or Warnings. They are issued
routinely once or twice a day.
Recommendation: PLAN
ends