I've always wanted to know how much precipitation (in rain mm) is
required to produce 1 foot of snow.

I've heard statements such as "1 foot of snow is equivalent to 1 inch
of rain" (ie: 12:1 ratio)
Ive also heard "1mm of rain is equivalent to 1cm of snow" (ie: 10:1
ratio)
Which one is correct?

In order to get the answer I performed the following experiment...

I took a pint beer-glass (one with an official pint crown and is 1
pint to the rim, not a lined glass)

I filled it as best as I could with snow, taking care not to get
air-gaps and also care not to compress the snow. The snow must be kept
"fluffy" and not compacted in.

I skimmed the top of the glass so that I have a pint of fluffy snow.
I brought the glass indoors and watched my pint of snow melt.

I was surprised how little water there was left in the glass!
I measured the water (in ml) and divided that number in to 568ml (one
pint)

Before posting my result, I'd be interested to see if somebody else
could perform the same experiment and we will then compare our
answers.

Its just a bit of fun,

regards

Brendan

"Brendan DJ Murphy" wrote in message
news
I've always wanted to know how much precipitation (in rain mm) is required
to produce 1 foot of snow.

I've heard statements such as "1 foot of snow is equivalent to 1 inch of
rain" (ie: 12:1 ratio)
Ive also heard "1mm of rain is equivalent to 1cm of snow" (ie: 10:1 ratio)
Which one is correct?

In order to get the answer I performed the following experiment...

I took a pint beer-glass (one with an official pint crown and is 1 pint to
the rim, not a lined glass)

I filled it as best as I could with snow, taking care not to get air-gaps
and also care not to compress the snow. The snow must be kept "fluffy" and
not compacted in.

I skimmed the top of the glass so that I have a pint of fluffy snow. I
brought the glass indoors and watched my pint of snow melt.

I was surprised how little water there was left in the glass!
I measured the water (in ml) and divided that number in to 568ml (one
pint)

Before posting my result, I'd be interested to see if somebody else could
perform the same experiment and we will then compare our answers.

Its just a bit of fun,

regards

Brendan
-----------------
Trouble is depending on the "type" of snow it can vary tremendously, by a
factor of two or more I believe.
Dave

"Dave Cornwell" wrote in
message ...

Trouble is depending on the "type" of snow it can vary tremendously,
by a factor of two or more I believe.
Dave


Good Point.

I'd say that "polystyrene pellet snow" is denser and has more water
per cubic cm than "large fluffy-flake snow".

It's the later that we've had today so this experiment should return
values of less water (ie: larger snow to rain ratio)

I have two more pints of snow slowly melting in my living room. I will
measure the water and post my results later.

I'd be grateful if others can do the same.

Brendan

Dave Cornwell wrote:


"Brendan DJ Murphy" wrote in message
news
I've always wanted to know how much precipitation (in rain mm) is
required to produce 1 foot of snow.

I've heard statements such as "1 foot of snow is equivalent to 1 inch of
rain" (ie: 12:1 ratio)
Ive also heard "1mm of rain is equivalent to 1cm of snow" (ie: 10:1
ratio) Which one is correct?

In order to get the answer I performed the following experiment...

I took a pint beer-glass (one with an official pint crown and is 1 pint
to
the rim, not a lined glass)

I filled it as best as I could with snow, taking care not to get air-gaps
and also care not to compress the snow. The snow must be kept "fluffy"
and not compacted in.

I skimmed the top of the glass so that I have a pint of fluffy snow. I
brought the glass indoors and watched my pint of snow melt.

I was surprised how little water there was left in the glass!
I measured the water (in ml) and divided that number in to 568ml (one
pint)

Before posting my result, I'd be interested to see if somebody else
could perform the same experiment and we will then compare our answers.

Its just a bit of fun,

regards

Brendan
-----------------
Trouble is depending on the "type" of snow it can vary tremendously, by a
factor of two or more I believe.
Dave


If I remember correctly, it can range from 4" to 18" of snow to 1" of
equivalent rainfall.

--
Graham P Davis, Bracknell, Berks., UK. E-mail: newsman not newsboy

In article ,
says...
I've always wanted to know how much precipitation (in rain mm) is
required to produce 1 foot of snow.

I've heard statements such as "1 foot of snow is equivalent to 1 inch
of rain" (ie: 12:1 ratio)
Ive also heard "1mm of rain is equivalent to 1cm of snow" (ie: 10:1
ratio)
Which one is correct?

In order to get the answer I performed the following experiment...

I took a pint beer-glass (one with an official pint crown and is 1
pint to the rim, not a lined glass)

I filled it as best as I could with snow, taking care not to get
air-gaps and also care not to compress the snow. The snow must be kept
"fluffy" and not compacted in.

I skimmed the top of the glass so that I have a pint of fluffy snow.
I brought the glass indoors and watched my pint of snow melt.

I was surprised how little water there was left in the glass!
I measured the water (in ml) and divided that number in to 568ml (one
pint)

Before posting my result, I'd be interested to see if somebody else
could perform the same experiment and we will then compare our
answers.



Several years ago, some colleagues and I looked at the snow/liquid ratio
for 1650 snowfall events from a number of sites in the US. The ratio
ranged from ~2:1 to ~50:1. Our mean was 15.6:1 and the median was 14:1
(we used 6-hour snow accuumlation obs-the ratios would be smaller for
longer time periods). The paper is online at

http://www.nssl.noaa.gov/~brooks/pap...reetal2006.pdf

Harold
--
Harold Brooks
Head, Mesoscale Applications Group
NOAA/National Severe Storms Laboratory

"Dave Cornwell" wrote in message
...

"Brendan DJ Murphy" wrote in message
news
I've always wanted to know how much precipitation (in rain mm) is
required to produce 1 foot of snow.

I've heard statements such as "1 foot of snow is equivalent to 1 inch of
rain" (ie: 12:1 ratio)
Ive also heard "1mm of rain is equivalent to 1cm of snow" (ie: 10:1
ratio)
Which one is correct?

In order to get the answer I performed the following experiment...

I took a pint beer-glass (one with an official pint crown and is 1 pint
to the rim, not a lined glass)

I filled it as best as I could with snow, taking care not to get air-gaps
and also care not to compress the snow. The snow must be kept "fluffy"
and not compacted in.

I skimmed the top of the glass so that I have a pint of fluffy snow. I
brought the glass indoors and watched my pint of snow melt.

I was surprised how little water there was left in the glass!
I measured the water (in ml) and divided that number in to 568ml (one
pint)

Before posting my result, I'd be interested to see if somebody else
could perform the same experiment and we will then compare our answers.

Its just a bit of fun,

regards

Brendan
-----------------
Trouble is depending on the "type" of snow it can vary tremendously, by a
factor of two or more I believe.
Dave

Just do the bloody experiment and lets get some results with the type of
snow used described as best you can, This is an eminently good experiment
and with so many on this news group maybe some meaningful answers
obtained.Dont put a fly in the ointment Dave ,bah humbug you old bugger
JP

On Feb 2, 5:41*pm, Harold Brooks wrote:
In article ,
says...



I've always wanted to know how much precipitation (in rain mm) is
required to produce 1 foot of snow.

I've heard statements such as "1 foot of snow is equivalent to 1 inch
of rain" *(ie: 12:1 ratio)
Ive also heard "1mm of rain is equivalent to 1cm of snow" (ie: 10:1
ratio)
Which one is correct?

In order to get the answer I performed the following experiment...

I took a pint beer-glass (one with an official pint crown and is 1
pint to the rim, *not a lined glass)

I filled it as best as I could with snow, taking care not to get
air-gaps and also care not to compress the snow. The snow must be kept
"fluffy" and not compacted in.

I skimmed the top of the glass so that I have a pint of fluffy snow.
I brought the glass indoors and watched my pint of snow melt.

I was surprised how little water there was left in the glass!
I measured the water (in ml) and divided that number in to 568ml (one
pint)

Before posting my result, *I'd be interested to see if somebody else
could perform the same experiment and we will then compare our
answers.

All a bit pointless as the OP has dictated the quality of snow to be
used. Hardly scientific.

Walking along the road nearby my place this afternoon, I saw that the
pavement one side was covered, whilst on the other it was almost bald.

There was a strip of grass between the road and the pavement on the
snowy side though the grass was covered too. Maybe salt splashes fall
through the blades and so the snow looks as thick as elsewhere?

Several years ago, some colleagues and I looked at the snow/liquid ratio
for 1650 snowfall events from a number of sites in the US. *The ratio
ranged from ~2:1 to ~50:1. *Our mean was 15.6:1 and the median was 14:1
(we used 6-hour snow accuumlation obs-the ratios would be smaller for
longer time periods). *The paper is online at

http://www.nssl.noaa.gov/~brooks/pap...reetal2006.pdf

Any tornadoes around 2 pm gmt today 'Arry?

On Feb 2, 4:44*pm, Graham P Davis wrote:
Dave Cornwell wrote:

"Brendan DJ Murphy" wrote in message
news
I've always wanted to know how much precipitation (in rain mm) is
required to produce 1 foot of snow.

I've heard statements such as "1 foot of snow is equivalent to 1 inch of
rain" *(ie: 12:1 ratio)
Ive also heard "1mm of rain is equivalent to 1cm of snow" (ie: 10:1
ratio) Which one is correct?

In order to get the answer I performed the following experiment...

I took a pint beer-glass (one with an official pint crown and is 1 pint
to
the rim, *not a lined glass)

I filled it as best as I could with snow, taking care not to get air-gaps
and also care not to compress the snow. The snow must be kept "fluffy"
and not compacted in.

I skimmed the top of the glass so that I have a pint of fluffy snow. I
brought the glass indoors and watched my pint of snow melt.

I was surprised how little water there was left in the glass!
I measured the water (in ml) and divided that number in to 568ml (one
pint)

Before posting my result, *I'd be interested to see if somebody else
could perform the same experiment and we will then compare our answers..

Its just a bit of fun,

regards

Brendan
-----------------
Trouble is depending on the "type" of snow it can vary tremendously, by a
factor of two or more I believe.
Dave

If I remember correctly, it can range from 4" to 18" of snow to 1" of
equivalent rainfall.

--
Graham P Davis, Bracknell, Berks., UK. *E-mail: newsman not newsboy- Hide quoted text -

- Show quoted text -

I'm surprised nobody has come up with their actual measurements
that should have been made this morning.
My gauge is a standard 5" gauge and I did a measurement last
night when the snow depth was about 6" and the gauge funnel slightly
"overflowing". This produced 8.7 mm equivalent rain. This morning
the gauge funnel was again full and the snow depth 28 cm and a further
12.6 mm was measured, total 21.3 mm. Thus the ratio in this case was
280:21.3, i.e. about 13.
There's been a bit more and the snow depth is now a full foot,
30+ cm.

Tudor Hughes, Warlingham, NE Surrey, 556 ft.

In article 8d88d8bd-bbf3-4587-9c25-9593ccc66882
@q30g2000prq.googlegroups.com, says...
[deletions]


Any tornadoes around 2 pm gmt today 'Arry?


Not in the US

Harold
--
Harold Brooks
NOAA/NSSL

In article ,
Brendan DJ Murphy writes:
I've always wanted to know how much precipitation (in rain mm) is
required to produce 1 foot of snow.

I've heard statements such as "1 foot of snow is equivalent to 1 inch
of rain" (ie: 12:1 ratio)
Ive also heard "1mm of rain is equivalent to 1cm of snow" (ie: 10:1
ratio)
Which one is correct?
snip

The answer is both/neither. The "drier" the snow, the more air it
contains and so the lower the water content. Dry snow will have the 10:1
or 12:1 ratio you quote. Really wet snow, close to turning to sleet/rain
can have a ratio as low as 4:1.
--
John Hall
"It is a very sad thing that nowadays there is so little useless
information."
Oscar Wilde (1854-1900)