Planetary Waves and the Hovmöller Diagram

Day-to-day weather features such as fronts and troughs, highs and lows constantly wash against New Zealand in the global atmospheric circulation.  Sometimes the weather in New Zealand is highly changeable, changing from heavy rain to blue skies with an almost daily frequency.  Other times the weather can seem to be stuck one way or another for days.  In this blog we discuss the reason for this: Planetary waves, also known as Rossby waves. We will also look at the tools forecasters have to analyse them, and the implications for New Zealand.

Women in Meteorology

Celebrating the increased participation of women in meteorology

March 2016

International Women’s Day is held every year in March and to mark this occasion we want to give a big shout out to all the great women working here at MetService. Since 2001 we have trained 34 women and 30 men to be World Meteorology Organisation (WMO) qualified meteorologists. Twenty years ago the statistics were very different.

Wellington Airport Sea Fog

The annual average fogs for Wellington Airport is 6 fogs per year, much rarer than at Christchurch (50 days per year) or Dunedin Airport (64 days per year) or Hamilton (92 days per year), yet it is very disruptive when it does roll in off the sea and can last for hours at a time.  Interestingly, Wellington gets more fog days in summer while fogs occur in winter for many other airports. Wellington airport is a hub for domestic commercial air traffic, therefore even short closures have major flow on effects for passengers and other airports around the country.

Himawari Satellite Data

The Japan Meteorological Agency launched a geostationary weather satellite called Himawari-8 in October 2014. “Himawari” means sunflower, and the name has been given to a series of satellites that we can look forward to in coming years. “Geostationary” means the satellite rotates “in sync” with the Earth, always above the same point over the equator.