What is the typical icing condition associated with Nimbostratus clouds?

Nimbostratus clouds are typically associated with widespread, continuous precipitation and can produce significant icing conditions for aircraft flying through or near them. The correct answer indicates that mostly rime ice is formed in these clouds, except when temperatures are just above freezing.

Rime icing occurs when supercooled water droplets freeze rapidly upon contact with a cold surface, particularly in conditions where there’s a high concentration of small droplets, like those found in Nimbostratus clouds. This cloud type often exists at colder temperatures and can contain supercooled water, making it conducive to rime icing, especially at lower altitudes.

Above freezing temperatures, the conditions change such that the likelihood of rime icing decreases. Instead, the precipitation may fall as rain rather than ice. Thus, aircraft operating in these layers can experience rime ice during colder conditions close to the cloud's base with more favorable conditions for icing just below the cloud base and above freezing.

This understanding highlights the specific nature of icing types associated with Nimbostratus clouds and how temperature plays a crucial role in determining the expected icing condition. Rime icing predominates when the temperatures are low, while at temperatures just above freezing, the likelihood of significant icing diminishes.