Weather Alerts for New York

This map shows recent moisture content over North America. Bright and colored areas show high moisture (ie, clouds); brown indicates very little moisture present; black indicates no moisture.

Weather Topic: What is Sleet?

Home - Education - Precipitation - Sleet

Sleet Next Topic: Snow

Sleet is a form of precipitation in which small ice pellets are the primary components. These ice pellets are smaller and more translucent than hailstones, and harder than graupel. Sleet is caused by specific atmospheric conditions and therefore typically doesn't last for extended periods of time.

The condition which leads to sleet formation requires a warmer body of air to be wedged in between two sub-freezing bodies of air. When snow falls through a warmer layer of air it melts, and as it falls through the next sub-freezing body of air it freezes again, forming ice pellets known as sleet. In some cases, water droplets don't have time to freeze before reaching the surface and the result is freezing rain.

Next Topic: Snow

Weather Topic: What are Stratocumulus Clouds?

Home - Education - Cloud Types - Stratocumulus Clouds

Next Topic: Stratus Clouds

Stratocumulus clouds are similar to altocumulus clouds in their fluffy appearance, but have a slightly darker shade due to their additional mass.

A good way to distinguish the two cloud types is to hold your hand out and measure the size of an individual cloud; if it is the size of your thumb it is generally an altocumulus cloud, if it is the size of your hand it is generally a stratocumulus cloud.

It is uncommon for stratocumulus clouds to produce precipitation, but if they do it is usually a light rain or snow.

Next Topic: Stratus Clouds