Why Does Snow Pack Better Near the Melting Point?

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  • Thread starter Thread starter Charles Link
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SUMMARY

The discussion centers on the optimal conditions for packing snow to create a snowman, specifically emphasizing that snow packs best when temperatures are just above freezing. The unique properties of water, including its expansion upon freezing, play a crucial role in this process. Participants share personal experiences, noting that wet snow, which typically occurs near the melting point, is essential for effective packing. The conversation also highlights misconceptions about snow packing, with some contributors arguing that the wetness of the snow is more significant than temperature alone.

PREREQUISITES
  • Understanding of thermodynamics, particularly phase changes of water.
  • Familiarity with the properties of snow, including wet and dry snow characteristics.
  • Knowledge of basic meteorological concepts related to temperature and precipitation.
  • Experience with snow-related activities, such as building snowmen or snowball fights.
NEXT STEPS
  • Research the thermodynamic properties of water and how they affect snow formation.
  • Explore the relationship between snow moisture content and temperature for optimal packing.
  • Investigate the physics of snowball formation and the role of pressure in snow compaction.
  • Learn about different types of snow and their implications for winter activities.
USEFUL FOR

This discussion is beneficial for winter sports enthusiasts, meteorologists, educators teaching about phase changes, and anyone interested in the science behind snow and its properties.

  • #121
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  • #122
The above are the latest photos of the snowmen in my backyard in Chicago=I'm now up to 5. The 5th snowman I made today, Monday January 22, 2024, from snow that we had on Friday, but temperatures were too cold for it to pack. Today it warmed up to 33 degrees, and the snow packed fairly well.
 
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  • #123
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  • #124
The above are the latest photos of the snowmen in my backyard in Chicago. I now have 6=this is the first year that I have ever had more than 2 at the same time. The one I made today, Tuesday January 23, 2024 is 4'3" tall. It is also from Friday's snow, like the one I made yesterday. It was too cold to pack until yesterday.
 
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  • #125
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  • #126
The above is a photo of the 2'6" snowman that I made on Friday 2-23-24. The photo was taken Saturday 2-24-24. This was the only snowman I was able to make this February, as we've had very springlike weather for much of February in Chicago. This snowman took a lot of work because there was very little snow to work with, and it came down too cold or too dry to pack well. (I'm posting this one a week later, because I forgot to post it a week ago). Very different from January where I had 6 snowman in the backyard a month ago. (see pictures above in previous posts).
 
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  • #127
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  • #128
The above is a photo of a 2'7" snowman that I made Friday 3-22-24. Packing conditions were good, but I had very little snow to work with. The photo was taken today, Saturday 3-23-24. We had almost no snow this March in Chicago. This is the first snowman I was able to make since about a month ago in February.
 
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  • #129
Charles Link said:
Packing conditions were good, but I had very little snow to work with.
I can see that. It seems you used up all the available snow. :smile:
 
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  • #130
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  • #131
The above is a photo of the 2'7" snowman I made Friday, 3-22-24. @DennisN This photo was taken just after I built the snowman. You can get a good idea of how much snow there was=and see where I rolled the balls to make the grass bare. By the next day, all the snow was gone (in the other picture), but I thought it would be worthwhile to post this picture as well. :)
 
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  • #132
Always nice to see grownups having/taking the time to goof around in the snow. :)

You think there's some psychology at play here? Missing your childhood, perhaps?

Nah, you're probably just goofing around. It's funnier with children though :P
 
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  • #133
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  • #134
The above is a photo of a 3'6" snowman that I made today, Thursday 11-21-24. We had our first snowfall of the season today in Chicago.
 
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  • #135
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  • #136
The above is a photo of a 4'4" snowman that I made today Friday December 20, 2024 in Chicago. Packing was ideal with temperatures at 35 degrees, but there is a cold wind out of the north, so the temperature will be dropping shortly. It's likely to be around at least through Christmas.
 
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  • #137
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  • #138
The above is a photo of a 5'6" snowman that I made today, Sunday 1-12-25, in my backyard in Chicago. Most of the snow came down 2 days ago, but it was too cold to pack. Today the temperatures warmed up to about 33 degrees, and the packing was ideal. It was very easy to make, the packing was so good.
 
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  • #139
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  • #140
The above is what is now (today Saturday 1-18-25) a 4'4" snowman that was 5'6" last Sunday. Yesterday the temperatures got to 42 degrees in Chicago and stayed in the upper 30's for an extended time. Today the weather has turned much colder and the forecast is for temperatures to be below freezing for perhaps a week or more with even a couple of days where it may reach zero degrees.

The snowman shrunk a lot yesterday and was even leaning a lot and I had to straighten it by slicing through between the base and middle sections and moving the top part a few inches, and then packing some snow between the layers. Looks like it may be around for at least another week. :)
 
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  • #141
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  • #142
The above is a photo of the 5'0 snowman that I made today, Saturday February 15, 2025, in Chicago. It snowed on Wednesday, but it was 27 degrees then and too cold to pack. Today it warmed up to about 33 degrees, so I was able to get the snow to pack. It also snowed a little more last night.
 
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  • #143
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  • #144
The above is a photo of a 2'6" snowman that I made today, Sunday 3-16-25. We had very little snow today in Chicago, so it took a lot of work to even get a 2'6" snowman. It packed very well though with temperatures around 33 degrees.
 
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  • #145
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  • #146
The above is a photo of the 3'6" snowman that I made today, Thursday 3-20-25, in Chicago. The snow packed fairly well at about 33 degrees, but I didn't have a lot of snow to work with.
 
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  • #147
Y U have all this snow? It spring.
 
  • #148
We had a ton of rain in Milwaukee yesterday. Guess 100 miles south, it turned to snow!
 
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  • #149
@Greg Bernhardt We had mostly rain in Chicago yesterday as well. It turned to snow around 2 am and accumulated a little around 3 am. I put most of the snowman together around 3:30 am when I made it to be 3'0". It snowed more over the next 3 or 4 hours though, so when I got up this morning at 8 am, I rolled the balls a little more and made it into 3'6". The overnight low was around 32 degrees.
Note: I used a dowel rod to hold the 3'0" snowman together, so it was easy to take apart and re-roll the balls. I didn't have enough snow to put any between the layers.
 
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  • #150
DrClaude said:
I think that this is completely wrong. The ability to make snowballs is related to the wetness of the snow. Dry snow is not sticky at all, whatever the temperature, and I think the amount of pressure needed to even partially melt it is beyond what you can achieve with your hands. When the snow is wet, no pressure is needed: simply taking a snowball and lightly putting it on fresh snow is enough to make additional stick to it.

There is often a link between the wetness of the snow and temperature: wet snow usually falls when temperatures are close to freezing. But I have often seen dry snow when the temperature is just below freezing. Likewise, old snow that has been on the ground all winter is rarely sticky, whatever the temperature.

Caveat: all this is based on personal experience of having lived nearly all my life in regions where snow is abundant. I have never dug deeper as to what actually makes snow wet and dry.
I'm impressed that we had to come this far into the thread for someone to offer an actual explanation! :smile:
 

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