It is a single house, a short distance from the runways of Zurich airport. The purpose of the white building with the large windows is not immediately obvious. At 3.10 pm, in bad weather, a woman steps out onto the terrace. She is concentrated, looking in different directions, almost as if searching for something. After a few minutes, her work outside is done. She leaves the terrace in her yellow reflective jacket, goes downstairs and sits down at her desk. There she enters data that is vital for air traffic around the world. 

The woman is Eliane Thürig. She is a weather observer for MeteoSwiss. Together with her colleagues, Thürig monitors the weather and helps pilots prepare for take-off or landing. This trip to the terrace will be repeated several times today. The next one is at 15.40.

The work that MeteoSwiss does at Zurich Airport and elsewhere is as complex and varied as the weather itself. Its task is to support safe air traffic with precise weather observations and forecasts.

Markus Kägi, a meteorologist by training, has been with MeteoSwiss for more than ten years. Over the course of an afternoon, he takes us to various stations that are relevant to weather observation and forecasting, and gives us an overview of the various measurements and observations that take place at Zurich Airport on a daily basis. Kägi is the perfect man for the job. The 40-year-old works not only as a forecaster, but also as a weather observer.

 

Behind the scenes on a flight to Miami

To make the work of MeteoSwiss more tangible, we present it using the fictional example of the Koller family. The family of five has booked a holiday they have been looking forward to for months. In just over 24 hours, they will be boarding a SWISS flight to Miami. While the Kollers are busy packing their bags, preparations for the flight are in full swing at the Operations Centre.

A SWISS dispatcher gathers all the necessary information before the flight. Weather data is particularly important. Both weather forecasts and weather measurements are used to ensure the highest level of safety.

On the one hand, the dispatcher collects the so-called TAFs (Terminal Aerodome Forecast). This is a weather forecast for the next 9 to 30 hours," explains Markus Kägi.

The TAF forecasts are only used in aviation and are produced by meteorologists around the world for their respective countries. For a flight like the Koller family's, therefore, weather forecasts are not only obtained for Zurich, but also for the destination of Miami and other airports that could serve as alternative destinations. Even before the flight, we find out what the weather is like at the airports where an emergency landing would be possible, for example. These weather forecasts are crucial for flight safety, says Kägi.

A TAF of this kind could therefore also ensure that the Koller family cannot board the flight at the scheduled time - for their own safety. This is the case, for example, if there is a hurricane in the USA," says Kägi. A flight can then be postponed. Forecasters generally rely on the forecasts of the countries concerned. But it can happen that there is no TAF at a Central African airport that serves as an alternate landing point for a SWISS flight to South Africa.    It may be necessary to determine the weather forecast from Zurich. This is a challenge, but it can be done," Kägi explains.  

 

Up-to-date data even during the flight

The pilot flying Kollers' plane to Miami also visits the office before the flight. The pilots receive the latest METAR when everyone is on board and before the aircraft takes off.  Enquiries can also be made once the aircraft is in the air," says Kägi.

The Koller family is already across the Atlantic. The pilot also receives the latest METAR during the flight and can therefore better assess the situation in Miami. The thunderstorm has passed over the city, so nothing stands in the way of a safe landing and a great holiday.

While the Koller family explores Miami, the experts at SWISS and MeteoSwiss are constantly monitoring the weather to ensure a safe return home.