Hours of Sun
The map shows how many hours of sun are expected for a given location in a day. The number of hours of sun depends on cloud cover, season, and geographic location of a location. In the polar regions of the North, for example, there can be up to 24 hours of sun in the summer months, depending on cloud cover, while at the same time, there is not a single hour of sun in the polar regions of the south.
Hours of sun, are illustrated by a red line that will vary as the value oscillates for the desired date.
Clouds Cover
Cloudiness is expressed in % over the maximum cloud cover. Cloudiness is often grouped into classes of 0-25%, 25-50% etc..
Zero percent means that there is no visible cloud in the sky. Fifty percent is equivalent to half the sky cloud cover. One hundred percent cloud cover means that clear sky is not visible. If cloud cover in multiple layers is fifty percent, only a low percentage of the sky will be visible.
Cloud cover is illustrated by the gray bars within the graph, which is also composed of the “T” bars that illustrate the possible maximum and minimum cloud cover values for the desired date.
Ultraviolet Index
The ultraviolet index (UV Index) is an international standard measure of the strength of ultraviolet (UV) radiation from the sun at a particular location on a given day. The goal is to help people effectively protect themselves from UV rays when exposure is excessive, causing burns, eye injuries such as cataracts, aging, and skin cancer
Public health organizations recommend people to protect themselves (for example, by applying sunscreen to the skin and wearing a hat) when the UV index is greater than or equal to 3.