The "Nebelmeer" (lit. sea of cloud) is a fabulous meteorological phonemenon at this time of year, caused by a band of low-lying, dense cloud in alpine valleys. A low level of air movement in the earlier parts of the day allows the morning dew to form cloud, then stay low in the valleys due to the cooler temperatures.
This particular weather usually leads locals and savvy visitors to jump in the car or onto the most convenient cable car or funicular to head up above the clouds and enjoy the glorious day which usually accompanies such conditions. If you’re ever in the lowlands of Switzerland near a mountainous area and wake up to a foggy morning, check the webcams of nearby peaks and head up and out!