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As the fog ceiling drops, the fog partially dissipates

the fog  Yesterday, Saturday, Switzerland was in the area of ​​influence of the low pressure system, which was in the process of separating into the western Miterranean. Moist Miterranean air was brought in by southerly and later southeasterly high winds. It reach from the south over the Alps and brought some precipitation to parts of eastern Switzerland. A layer of high fog was present over the lowlands, the upper limit of which rose to over 1000 metres during the course of the day, but also dissipat in some areas.

This morning, the high fog reach far into the foothills of the Alps, as here in the Alpstein near Weissbad AI. (Meteo report app) 

High pressure influence will be noticeable on Sunday

 

After the weather on Saturday, which was still dominat by low pressure, high pressure began to influence the situation today, Sunday. In the gap that was creat when the low separat over the Alps, a high pressure bridge form, which creat a connection between the Azores high and the high over Eastern Europe. This mark the beginning paraguay mobile database of subsidence, i.e. the large-scale sinking, which increasingly dri out the air mass from above and thus also affect the fog.

Satellite image sequence from today 09:00 to 15:30, showing the dissolution of the fog cover over the northern side of the Alps. (Meteosat/MeteoSwiss) 

Fog ceiling is decreasing

 

The cool, moist air, and thus the fog layer, over the lowlands on the northern side of the Alps had a relatively high upper limit of around 1200 meters on Sunday morning, which is actually more typical for high pressure systems with a bise. Since the weather situation was in a transition phase from a low pressure situation to a high pressure situation, “equilibrium” had not yet been reach. But with the onset of subsidence on Sunday morning, the inversion and thus the fog upper limit gradually sank and was still at around 1100 meters after midday.

Vertical profiles of the radio soundings from Payerne 00 and 12 UTC. The light blue bar marks the fog layer. It is clearly visible that the fog ceiling was higher and the fog thickness was greater in the early morning than at midday. In addition, the upper air layers above it warm up and dri out. (MeteoSwiss)

The fog layer was still quite thick in the early morning, at almost 900 metres. create your custom web pages with divi builder For a short time, its upper limit even rose slightly and there was a light drizzle in places. But with the increasing influence of high pressure and the drying be numbers from above, the fog upper limit sank and the fog began to appear holes. With the generally southerly winds at altitude, the valleys in the foothills of the Alps were initially favour for the fog to clear. With northerly winds or a bise, it would be the other way round. By the afternoon, most of the fog had clear. Only in eastern Switzerland was it more persistent.

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