Types of Precipitation

CLOUDS and PRECIPITATION
Day 3

Multiple Choice

Which of the following four forms of precipitation would most likely be a solid that falls during a summer storm?

• snow

• sleet

• hail

• rain

​I. Clouds and Precipitation

• Precipitation is water that falls from the sky.

• Water falling from the sky comes from a cloud: usually a stratus or a cumulus cloud.

  • Cumulus clouds look like puffy white cotton balls drifting across the sky.

  • Cumulus clouds move across the sky, moving water around the surface of the Earth.​

Multiple Choice

True or False

Cumulus clouds do bring rain.

• True

• False

• ​As a cumulus cloud makes its journey over the Earth, it may continue to pick up moisture, and grow in size.

• Cumulus clouds on a hot day can grow rapidly as the Sun’s energy heats the surface of the Earth.

• A cumulus cloud may grow larger and darker as it picks up more moisture from the ground below.

  • Soon, the top of the cloud can be high in the atmosphere, and begin to spread out: the cumulus cloud has formed a thunderhead.

  • It is now a cumulonimbus cloud: a nimbus cloud is any cloud that is raining.

Multiple Choice

A nimbus cloud is any cloud that is ________________.

• flat

• fluffy

• dark

• raining

• ​Rainfall can also come from a stratus cloud.

• Stratus clouds form layers of clouds that spread across the whole sky.

  • There are few breaks for the Sun to shine through when stratus clouds are overhead.

  • Stratus clouds, when they begin to rain, are known as nimbostratus.

    • Rainfall from a nimbostratus cloud is slow, steady, and can last for days.

Multiple Choice

Rainfall from a nimbostratus cloud is __________ and can last for days.

• hard and fast

• slow and steady

• extreme and dangerous

• intense

• ​Rainfall is liquid water that falls from the sky, or precipitates, as drops.

• The drops are usually small in size, about the size of the eraser of your pencil. Sometimes they can be larger, but not by much.

• Florida’s rainy season is in the summer, driven by the heat of the Sun.

• During the winter, rainfall happens much less, and the winter is known as the dry season.

  • Occasional rainfall happens: it is during the winter that nimbostratus clouds bring gentle rains that last for a day or more.

SNOW

• If the temperature of the air is below thirty‐two degrees Fahrenheit at the ground, and gets colder moving higher in the atmosphere, precipitation can fall as a solid: snow.

• Snow is a form of precipitation that forms as a solid when the air temperature inside a cloud is below freezing, and is below freezing all the way to the ground.

• Snow is rare in Florida.

Multiple Choice

________is a form of precipitation that forms as a solid when the air temperature inside a cloud is below freezing, and is below freezing all the way to the ground.

• hail

• sleet

• snow

• ra

• If rain begins to fall from a cloud as a liquid and passes through a layer of freezing air above or at the ground, rain can freeze and become sleet.

• Sleet is a form of precipitation that begins as a liquid, and freezes on its way to the ground.

• Sleet pellets are about the size of the eraser on your pencil or smaller.

• Sleet is rare in Florida.
  
  

​SLEET

Multiple Choice

Sleet is a form of precipitation that begins as a ________, and freezes on its way to the ground

• liquid

• solid

• piece of snow

• piece of hail

• ​Thunderstorms rise high into the atmosphere where temperatures are very cold.

• Wind currents inside a thunderstorm can blow rainfall back up into a higher level of the cloud, where the water droplets freeze and form ice.

• If they then fall to the ground as ice they are known as hail.

• However, violent thunderstorms can blow even the hailstones back into the clouds, where they can become larger.

  • This can happen many times, making hailstones the size of golf balls, baseballs, or larger.

​HAIL

Multiple Choice

_________________can blow even the hailstones back into the clouds, where they can become larger.

• Summer storms

• Rain showers

• Violent thunderstorms

• The Water Cycle

Multiple Choice

On a February day in Pensacola, in the northwest corner of Florida, low cloud cover filled the sky. Light rainfall began falling in the morning, with temperatures in the high 30’s. By noon, the temperature had fallen to below freezing, and the precipitation changed to a solid. Temperatures in the clouds and all the way to the ground were below freezing. What form of precipitation was falling in Pensacola?

• rain

• snow

• sleet

• hail