Blizzards form when a strong low pressure area is near a high pressure area, causing sustained winds over 35 mph that reduce visibility to less than 1/4 mile due to blowing or drifting snow over a period of at least 3 hours. While blizzards typically occur where temperatures are cold enough to snow, they can also form in unusual places like Iran. Notable blizzards include the 1972 Iran blizzard that killed 4,000 people and the 1888 Children's Blizzard in the US that killed many children unaware of the rapidly forming conditions. Blizzards are dangerous due to their deadly winds and ability to form suddenly.

1. By
SIMON & COLLIN

2.  Blizzard winds are created when a strong low
pressure area is close to a strong high pressure
area.
 During a blizzard,
relative humidity is
around 100%.
 There is no
temperature criteria
for blizzards to form.

3.  You must Have:
 sustained winds or frequent gusts that are greater
than or equal to 35 mph.
 blowing or drifting snow which reduces visibility to
400 meters or ¼ mile or less
 must last for a prolonged period of time — typically
three hours or more.
 Blizzard winds are created when a strong low
pressure area is close to a strong high pressure
area.

4.  Typically, blizzards can only form where it gets
cold enough to snow.
 In the Great Plains of the U.S., in eastern and central
Canada, and in Russia.
 But blizzards can also form in unusual places, such
as Iran, as we will show you later.

5. The Iran Blizzard of February 1972
 resulted in the deaths of approximately 4,000
people
 lasting from February 3 to February
9, 1972, dumped more than ten feet of snow
accumulation

6. The Children’s Blizzard in 1888 in the U.S.
 The majority of the 230 people who died were
children, who were caught unaware as they
walked home from school.
 The arctic air swept in
from the north and
mixed with air that
was packed with
moisture from the south,
creating blizzard
conditions at a rapid level.

7.  Blizzards are a very dangerous weather system
that can form out of nowhere with deadly
winds and temperature.