How to Read Clouds on the Trail

Find a spot on the trail where you can have a clear view of the sky.

Look above and observe the clouds. You can identify the clouds by height and shape. Three major types of clouds are low, middle or high clouds, and the three main cloud shapes are cumulus, stratus and nimbus.

Estimate the height of the clouds. According to National Aeronautics and Space Administration or NASA, low-level clouds are usually flat and layered or rounded on top with flat bases and are found below 6,500 feet. Mid-level clouds usually look flat or layered and range about 6,500 to 20,000 feet. High clouds usually look thin and patchy and are above 20,000 feet.

Read the clouds by determining the cloud's shape relative to its height. Low-level clouds are either stratocumulus, cumulus, stratus or nimbostratus. Stratocumulus are large and dark. They are shaped in rounded masses and are usually in groups, waves or lines across the sky. These type of clouds can be signs of light rain or even snow, depending on temperature. They may also indicate that storms are coming. Cumulus clouds have clear-defined edges and look like puffy cotton and cauliflower-like. They typically indicate fair weather. Stratus clouds are flat, thin and uniform in layers. They indicate cloudy days and can bring about light drizzle. Nimbostratus clouds appear gray and foggy; they usually cover the whole sky and drop rain or snow.

Read mid-level clouds by identifying their shapes. Mid-level clouds are either altocumulus or altostratus. Altocumulus are puffy and gray or white in color.They can be lined up in rows or appear patchy with spaces between them. They indicate a preceding cold front or the possibility of thundershowers. Altostratus are bluish gray or gray in color. They appear to be uniform-looking and cover much of the sky. They typically form ahead of storms with snow or rain.

Read high clouds, which are either cirrus, cirrocumulus or cirrostratus. Cirrus clouds appear like delicate hooks or fibrous strands. They predict fair weather but are also signs of a change in weather within 24 hours. Cirrocumulus are thin and patchy with wavelike patterns. These clouds tend to be really high in the sky and have unpredictable impact on weather patterns. Cirrostratus are sheetlike clouds with thin shapes. They cover most of the sky and can be warnings that rain or snow will fall within the next 12 to 24 hours.