|by jonseidman1988 on Flickr
- Winter storms usually form when an air mass of cold , dry , Canadian air moves south and interacts with a warm , moist air mass moving north from the Gulf of Mexico.
- The point where these two air masses meet is called a front.
- If cold air advances and pushes away the warm air, then it turns into a cold front.
|by dobak on Flickr
How do ice storms form?
- Ice Storms form when a layer of warm air is between two layers of cold air.
- Frozen precipitation melts while falling into the warm air layer ,and then proceeds to refreeze in the cold layer above the ground.
- This creates freezing rain or a glaze of ice.
Ice storms can cause car crashes because it can be very slippery and people cannot see signs.
Ice storms are also bad because when it is very cold people can get very sick.
|by wfyurasko on Flickr
How do blizzards form?
- Blizzards are long-lasting snow storms with strong winds and intense snowfall.
- Three things needed to make a blizzard:
- cold air (below freezing) is needed to make snow
- lots of moisture to form clouds and precipitation
- warm rising air to form clouds and cause precipitation
Blizzards are very dangerous when you are traveling in the winter months. Blizzards can strand cars on high ways for hours and even days!
|just a moment! Snow Crystal
|by elif ayse on Flickr
How are snowflakes made?
- Snowflakes are made of ice crystals.
- Each snowflake is six-sided and made of as many as two hundred ice crystals.
- Snowflakes form in clouds below freezing temperature.
- The ice crystals form around tiny bits of dirt that have been carried up into the atmosphere by the wind.
- As the snow crystals grow, they become heavier and fall towards the ground.
|2010 02 06 - 1053 - Washington DC - 12th St from V St
|by thisisbossi on Flickr
How does snow form?
- Snow is commonly formed when water vapor undergoes deposition, which is when water vapor changes directly to ice without first becoming a liquid, high in the atmosphere at a temperature of less than 32°F and then falls to the ground.