molntäcke

Molntäcke (Swedish for "cloud blanket") is a meteorological term that describes a broad, continuous layer of clouds covering large portions of the sky, producing an overcast appearance. Although not always a formal technical term, it is widely used in weather reporting and everyday language to convey extensive cloudiness.

Formation occurs when moist air is cooled and spreads laterally, forming stratiform clouds such as stratus, stratocumulus, or nimbostratus. The resulting deck can have bases from near the ground to several hundred meters up, and may persist for hours or days under stable atmospheric conditions.

Effects include reduced solar radiation, cooler daytime temperatures and relatively mild nights, and a tendency toward drizzle or light precipitation if the layer thickens. The cloud blanket can influence visibility and road conditions and often affects agricultural and tourism activities.

Geographically, molntäcke is common in mid-latitude regions and along coasts where marine air masses encounter land. It is more frequent in autumn and winter in many temperate climates.

In meteorology, cloud cover is typically expressed in oktas or as a percentage of the sky obscured. While molntäcke is an informal phrase, it captures the idea of a nearly continuous cloud deck that contrasts with broken or scattered cloud fields.

Etymology: moln means cloud and täcke means blanket in Swedish. The image is akin to English phrases such as "cloud blanket" or "overcast."