molnigheten

Molnigheten is the Swedish term for cloudiness, referring to the fraction of the sky covered by clouds at a given time and place. It is a central concept in meteorology and is used to describe how cloudy or clear the sky appears to observers, pilots, and the general public.

Measurement and classification: Cloudiness is commonly expressed in oktas (eighths of the sky) from 0 to 8, or as a percentage. Typical categories are 0/8 clear, 1–2/8 few, 3–4/8 scattered, 5–7/8 broken, and 8/8 overcast. In Swedish forecasts, descriptors such as klar (clear), delvis molnigt (partly cloudy), mulet (cloudy), and helt molnigt (completely cloudy) are used to convey the same idea.

Observation and data collection: Cloudiness is estimated by trained weather observers, supported by automated instruments such as ceilometers, all-sky cameras, and satellite imagery. In international meteorology, cloud cover is reported in METAR and synoptic forecasts using octas or standard codes (FEW, SCT, BKN, OVC).

Implications and uses: Molnigheten affects daylight and surface temperatures, humidity, and the potential for precipitation. It is important for aviation safety, solar-energy planning, agriculture, and outdoor activities, and shows characteristic seasonal and regional patterns.

See also: Sky condition, Cloud cover, Weather forecasting.