© Lorem ipsum dolor sit Nulla in mollit pariatur in, est ut dolor eu eiusmod lorem 2014
Weather Glossary
Frost and Ice
They are several types of weather common to the UK below is a quick description
Ground Frost
Ground frost occurs where ice forms on the ground where the temperatures has fallen below the freezing
point of water. Ground frost occurs more frequently than Air frost due to the fact that the ground can lose
heat much quicker than the surrounding air. In recent times lazy presentations on the TV have allowed the
term grass frost to be used. This is unofficial and inaccurate and the term shouldn’t be used. I can’t see the
term Windscreen frost be used when Ice only forms on Car Windscreens. The only reason why frost is
more prevalent on Grass at times is because concrete can hold onto the heat better. However the correct
terms are Ground Frost and not Grass Frost.
Air Frost
An Air Frost occurs when the temperature falls below the freezing point of water at a height of at least One
Meter above ground.
Hoar Frost
Hoar frost forms the same as Dew but instead of water droplets Ice Crystals form on objects that have
dropped below zero by radiation cooling. The air crystals get attached to Trees Leaves as they interlock
creating the Winter wonderlands that we are familiar with. At times Hoar frost can may become so thick it
may give the appearance of Snow.
Image by http://www.hd2wallpapers.com
Hoar Frost may also form from dew as temperatures drop to around -3C to -5C. This also know as Silver
Frost or White frost. Hoar frost can also be derived from sublimation. It’s also easy to confuse Hoar frost
with Rime or Glaze.
Rime
Rime is a granular deposit of ice which maybe white or Milky in appearance. This is formed by rapid
freezing of super cooled water on cold exposed objects. Rime may also form feathers which point into
the wind. Under calm conditions they may form in any direction. This why it’s confused with Hoar Frost.
Rime is created via foggy conditions or by cloud droplets. These droplets which are supercooled freeze as
soon as they make contact with any object. If the fog persists large amounts of ice can be formed. This
may cause structural damage.
Glaze or Black Ice
Glaze forms when supercooled liquid precipitation falls in the form of freezing rain or drizzle onto
exposed objects at or just above zero. The liquid doesn’t freeze instantly allowing the liquid to spread out
forming a thin layer of smooth ice.
Unlike Hoar Frost or Rime the glaze is transparent. Glaze or Black ice tend to occur when a warm air mass
displaces a cold air mass.
© Lorem ipsum dolor sit Nulla in mollit pariatur in, est ut dolor eu eiusmod lorem 2014
Frost and Ice
Weather Glossary
They are several types of weather common to the UK below is a quick description
Ground Frost
Ground frost occurs where ice forms on the ground where the temperatures has fallen below
the freezing point of water. Ground frost occurs more frequently than Air frost due to the fact
that the ground can lose heat much quicker than the surrounding air. In recent times lazy
presentations on the TV have allowed the term grass frost to be used. This is unofficial and
inaccurate and the term shouldn’t be used. I can’t see the term Windscreen frost be used when
Ice only forms on Car Windscreens. The only reason why frost is more prevalent on Grass at
times is because concrete can hold onto the heat better. However the correct terms are Ground
Frost and not Grass Frost.
Air Frost
An Air Frost occurs when the temperature falls below the freezing point of water at a height of
at least One Meter above ground.
Hoar Frost
Hoar frost forms the same as Dew but instead of water droplets Ice Crystals form on objects
that have dropped below zero by radiation cooling. The air crystals get attached to Trees Leaves
as they interlock creating the Winter wonderlands that we are familiar with. At times Hoar frost
can may become so thick it may give the appearance of Snow.
Image by http://www.hd2wallpapers.com
Hoar Frost may also form from dew as temperatures drop to around -3C to -5C. This also know
as Silver Frost or White frost. Hoar frost can also be derived from sublimation. It’s also easy to
confuse Hoar frost with Rime or Glaze.
Rime
Rime is a granular deposit of ice which maybe white or Milky in appearance. This is formed by
rapid freezing of super cooled water on cold exposed objects. Rime may also form feathers
which point into the wind. Under calm conditions they may form in any direction. This why it’s
confused with Hoar Frost. Rime is created via foggy conditions or by cloud droplets. These
droplets which are supercooled freeze as soon as they make contact with any object. If the fog
persists large amounts of ice can be formed. This may cause structural damage.
Glaze or Black Ice
Glaze forms when supercooled liquid precipitation falls in the form of freezing rain or drizzle
onto exposed objects at or just above zero. The liquid doesn’t freeze instantly allowing the liquid
to spread out forming a thin layer of smooth ice.
Unlike Hoar Frost or Rime the glaze is transparent. Glaze or Black ice tend to occur when a
warm air mass displaces a cold air mass.
© Lorem ipsum dolor sit Nulla in mollit pariatur in, est ut
dolor eu eiusmod lorem 2014
Frost and Ice
Weather Glossary
They are several types of weather common to the UK below is a quick
description
Ground Frost
Ground frost occurs where ice forms on the ground where the
temperatures has fallen below the freezing point of water. Ground frost
occurs more frequently than Air frost due to the fact that the ground
can lose heat much quicker than the surrounding air. In recent times
lazy presentations on the TV have allowed the term grass frost to be
used. This is unofficial and inaccurate and the term shouldn’t be used. I
can’t see the term Windscreen frost be used when Ice only forms on
Car Windscreens. The only reason why frost is more prevalent on Grass
at times is because concrete can hold onto the heat better. However
the correct terms are Ground Frost and not Grass Frost.
Air Frost
An Air Frost occurs when the temperature falls below the freezing point
of water at a height of at least One Meter above ground.
Hoar Frost
Hoar frost forms the same as Dew but instead of water droplets Ice
Crystals form on objects that have dropped below zero by radiation
cooling. The air crystals get attached to Trees Leaves as they interlock
creating the Winter wonderlands that we are familiar with. At times
Hoar frost can may become so thick it may give the appearance of
Snow.
Image by http://www.hd2wallpapers.com
Hoar Frost may also form from dew as temperatures drop to around -
3C to -5C. This also know as Silver Frost or White frost. Hoar frost can
also be derived from sublimation. It’s also easy to confuse Hoar frost
with Rime or Glaze.
Rime
Rime is a granular deposit of ice which maybe white or Milky in
appearance. This is formed by rapid freezing of super cooled water on
cold exposed objects. Rime may also form feathers which point into
the wind. Under calm conditions they may form in any direction. This
why it’s confused with Hoar Frost. Rime is created via foggy conditions
or by cloud droplets. These droplets which are supercooled freeze as
soon as they make contact with any object. If the fog persists large
amounts of ice can be formed. This may cause structural damage.
Glaze or Black Ice
Glaze forms when supercooled liquid precipitation falls in the form of
freezing rain or drizzle onto exposed objects at or just above zero. The
liquid doesn’t freeze instantly allowing the liquid to spread out forming
a thin layer of smooth ice.
Unlike Hoar Frost or Rime the glaze is transparent. Glaze or Black ice
tend to occur when a warm air mass displaces a cold air mass.
