A sky with little or no cloud cover (0–1 okta). Maximum solar radiation and temperature reach.
basicWhat is Clear Sky?
Clear skies allow maximum solar heating during the day but also maximum radiative cooling at night, producing the largest daily temperature range. In tropical climates, clear skies are more common during the dry season. The WMO weather code 0 (Clear sky) corresponds to the ☀️ icon in weather apps.
Key points
- A sky with little or no cloud cover (0–1 okta). Maximum solar radiation and temperature reach.
- Category: basic
Related terms
See also: clear-sky is connected to other weather concepts. Browse the full glossary for related definitions.