Details: the drivers behind the forecast Güttingen

West/East High-Altitude Winds

Shown is the wind at about 1.5 km altitude (850 hPa) above the spot: upwards the share from the west, downwards the share from the east, plus the direction (right axis).

This wind depends on the large-scale weather pattern. When it blows strongly from one direction, the surface wind usually comes from a similar one.

North-South High-Altitude Winds

Shown is the wind at about 1.5 km altitude (850 hPa) above the spot: upwards the share from the north, downwards the share from the south.

A strong southerly share goes with foehn and ahead of fronts, a northerly share often brings cooler air.

Bise: pressure Geneva minus Konstanz

Shown is the air pressure in Geneva minus the air pressure in Konstanz. If the value is negative (down), the higher pressure lies to the north-east and cool air flows south-west between the Jura and the Alps: the Bise. The larger the difference, the stronger it blows, usually more during the day than at night.

In our measurements in Güttingen, from −3 hPa a wind of 11 knots or more from the north-east blew in 16 % of the hours between 5 am and 7 pm, above −1 hPa in 0 %.

Cold air after thunderstorms

Shown are the thunderstorm energy (CAPE) at the spot and the difference between temperature and dew point (right axis).

In thunderstorms rain evaporates and cools the air. The cold, heavy air plunges down and spreads along the ground as a gust front. The drier the air near the ground, i.e. the larger the gap to the dew point, the more it cools and the stronger the wind becomes.

In our measurements in Güttingen, on thunderstorm days with a gap of 10 degrees or more it became at least 2 degrees colder within one hour on 88 % of the days, with moister air on 49 %.