No. As a rule of thumb 38 degrees is the "cut-off" for snowfall.
It all depends upon the temperature in the upper and middle layers of the atmosphere.
Krazy: sleet forms, not hail. Hail can occur at 90 degrees, when updrafts continually bring melting ice crystals back up in the cold upper atmosphere, where it refreezes. This continues until the hailstone is heavy enough to overcome the updraft, and falls to the Earth.
The temp. at ground level can be way above freezing, hence hail. The temp in the upper atmosphere however, must be at or below freezing. I live in michigan where there are alot of times that this happens. the snow will melt soon after it hits the ground. If you want to get an accumulation not only does the temp. have to be below freezing but the ground must be frozen as well or else heat sink from the ground will also melt the snow.
Shibi is right as well, usually durring a snow storm it is quite comfortable outside (40 ish) the snow can be packed easily, great for snowball fights. When temps are very low 20 or under it's what is known as powder snow.
No but the upper atmosphere has to be below freezing in order for there to be snow and the snow needs to be large enough and fall fast enough for the snow to come down through the non freezing parts of the atmosphere. This is why you can have a 40 degree day and still have snow, although the snow will not stick and will melt on contact with anything.
The part of the cloud where the snow forms has to be below zero degrees Celsius. (32 degrees F) to be able to form any kind of snow.
In fact, snow forms the best and easiest at temperatures between -10 degrees C. to -20 degrees C.
As long as there is not a layer of air that is above freezing that is thick enough and warm enough (usually 4 degrees C for at least 500 Meters) that will melt the snow, it will reach the surface as snow. Surface temperatures of up to 6 degrees C have been observed with snow.
Freezing rain will often start as snow, fall through a thick warm layer that melts the snow, and then obtain temperatures below freezing again but not freeze until it hits something at the surface. Surface temperatures a degree either side of -2 degrees C, works best for that.
The snow forms in clouds, which have two different factors then we encounter down on the ground.
First, the most obvious is that the clouds are at a much lower temperature and the snow will form there and then begin to melt as it drops down to the ground. If the air temperature on the ground is warmer the 32 degree's farenheight or 0 celcius, the snow will melt, so for the snow to stay it must be below freezing.
The second and less obvious is that when the snow forms, it forms at a much higher altitude which affects the ammount of pressure on the molcules. The snow forms much easier at a higher altitude. An example of this is when you go to the mountains, you have to cook your food ad a higher temperature then you normally would have to cook your food just because of the change in atmospheric pressure.
Not nesacarliy I have seen it as high as 42 Deg F Surfface tempature and have it snowing.
the upper atmosphere temps were below freezing and the snow fell fast and heavy but in order for snow to form the tempature does have to be below freezing.
Nope. Often it "warms up" for a snow -- warms up to above 32*F. I've been in falling snow where the temperatures were in the 40* range. I've also seen snowflakes (clusters) larger than cotton balls. I love snow!
Comments
No. As a rule of thumb 38 degrees is the "cut-off" for snowfall.
It all depends upon the temperature in the upper and middle layers of the atmosphere.
Krazy: sleet forms, not hail. Hail can occur at 90 degrees, when updrafts continually bring melting ice crystals back up in the cold upper atmosphere, where it refreezes. This continues until the hailstone is heavy enough to overcome the updraft, and falls to the Earth.
The temp. at ground level can be way above freezing, hence hail. The temp in the upper atmosphere however, must be at or below freezing. I live in michigan where there are alot of times that this happens. the snow will melt soon after it hits the ground. If you want to get an accumulation not only does the temp. have to be below freezing but the ground must be frozen as well or else heat sink from the ground will also melt the snow.
Shibi is right as well, usually durring a snow storm it is quite comfortable outside (40 ish) the snow can be packed easily, great for snowball fights. When temps are very low 20 or under it's what is known as powder snow.
No but the upper atmosphere has to be below freezing in order for there to be snow and the snow needs to be large enough and fall fast enough for the snow to come down through the non freezing parts of the atmosphere. This is why you can have a 40 degree day and still have snow, although the snow will not stick and will melt on contact with anything.
The part of the cloud where the snow forms has to be below zero degrees Celsius. (32 degrees F) to be able to form any kind of snow.
In fact, snow forms the best and easiest at temperatures between -10 degrees C. to -20 degrees C.
As long as there is not a layer of air that is above freezing that is thick enough and warm enough (usually 4 degrees C for at least 500 Meters) that will melt the snow, it will reach the surface as snow. Surface temperatures of up to 6 degrees C have been observed with snow.
Freezing rain will often start as snow, fall through a thick warm layer that melts the snow, and then obtain temperatures below freezing again but not freeze until it hits something at the surface. Surface temperatures a degree either side of -2 degrees C, works best for that.
The snow forms in clouds, which have two different factors then we encounter down on the ground.
First, the most obvious is that the clouds are at a much lower temperature and the snow will form there and then begin to melt as it drops down to the ground. If the air temperature on the ground is warmer the 32 degree's farenheight or 0 celcius, the snow will melt, so for the snow to stay it must be below freezing.
The second and less obvious is that when the snow forms, it forms at a much higher altitude which affects the ammount of pressure on the molcules. The snow forms much easier at a higher altitude. An example of this is when you go to the mountains, you have to cook your food ad a higher temperature then you normally would have to cook your food just because of the change in atmospheric pressure.
Not nesacarliy I have seen it as high as 42 Deg F Surfface tempature and have it snowing.
the upper atmosphere temps were below freezing and the snow fell fast and heavy but in order for snow to form the tempature does have to be below freezing.
No, the high atmosphere maybe below freezing causing the snow.
Nope. Often it "warms up" for a snow -- warms up to above 32*F. I've been in falling snow where the temperatures were in the 40* range. I've also seen snowflakes (clusters) larger than cotton balls. I love snow!
34 degrees farenheit...which is zero degrees celsuis and freezing point
edit: the air temp has to be at or below freezing but not the ground temp
It's usually below freezing or if it's above it would be no more than 5 degrees above it.