Predicting the Weather with Clouds Name Picture Prediction High Clouds Cirrus curly or wispy point in the direction the wind is blowing change in weather will occur within 24 hours Cirrostratus Cirrocumulus come 12-24 hours before a rain or snow storm seen in the winter and indicate fair, but cold, weather In the tropics, they may indicate an approaching hurricane. Medium Clouds *** Something Coming *** forms ahead of storms with continuous rain or snow Altostratus cold front coming Altocumulus if warm thunderstorm coming Low Clouds Stratus layered light mist or drizzle cloud touching the ground - fog Rain rarely occurs. Stratocumulus can turn into Nimbostratus Nimbostratus rain or snow Vertical Clouds Cumulus low "fair weather" clouds fluffy like popcorn heavy rain, snow, hail, lightning, and tornadoes Cumulonimbus