Too cold to Snow?

[YT2095]

has anyone ever heard someone say that it`s "Too cold to snow"?

 

I know I have, and I`ve often wondered what it means, and when confronting such people with "what do you mean" you usualy get back "because it is" yeah right, some answer that is!

 

now I`m thinking of the north or South pole here the temp is often -20 or lower and it`s like snowing all the time there! so what`s this "It`s too cold to snow" business all about?

 

any ideas?

[mossoi]

Here's a couple of explanations I've found:

 

"If it is too cold, the atmosphere can not hold water.

No water, no snow.

The most prominent example of this is Antartica, the south pole. The

precipitation at the south pole is minimum, to the extent that it is

categorized as a desert. The precipitation that falls does not melt readily."

 

Harold Myron

 

 

"The temperature of the air affects the amount of water vapor it can hold.

Colder air holds less water. To have a significant snow, you need

significant water vapor in the air. At temperatures well below freezing

there is not enough water in the air to get much snow.

 

The exception to this is in places on the lee side of a large body of

water. Here the air need not hold much water, but only keep blowing."

 

Larry Krengel

[mossoi]

Here's something else that seems to be more thought out:

 

"One phrase that is heard time to time is that, "it is too cold to snow today". In actuality, earth's atmosphere is not too cold to snow but rather it is "too dynamically stable to snow". Dynamic stability may be present due to low-level cold air advection, a lack of upper level divergence, and/or a lack of low level convergence. Also, if dynamic lifting does occur it may not produce precipitation that reaches the surface due to low RH values in the lower troposphere.

 

The ingredients for snow are: (1) a temperature profile that allows snow to reach the surface, (2) saturated air, and (3) enough lifting of that saturated air to allow snow to develop aloft and fall to reach the surface. In a situation when it is said "it is too cold to snow" there is in reality not enough lifting of air that causes snow to reach the surface.

 

The phrase "it is too cold to snow today" probably originated as a misapplication of the relationship between temperature and the maximum amount of water vapor that can be in the air. When temperature decreases, the maximum capacity of water vapor that can be in the air decreases. Therefore, the colder it gets the less water vapor there will be in the air.

 

Even at very cold surface temperatures significant snowfall can occur because: (1) intense lifting can produce significant precipitation even at a very low temperature, (2) the temperature aloft can be much warmer than the temperature at the surface. The relatively warmer air aloft can have a larger moisture content than air in the PBL, (3) Moisture advection can continue to bring a renewed supply of moisture into a region where lifting is occurring, (4) Even at very cold temperatures the air always has a capacity to have some water vapor. "

 

METEOROLOGIST JEFF HABY

[YT2095]

thnx man

[mossoi]

No bother - I've heard this a lot myself and have always questioned it. My personal idea has been that the water is unable to gather into large enough clumps to fall - possibly because it is freezing too quickly and staying as a fine powder rather than clumping and then freezing..

 

It seems that there may be several factors though.

[YT2095]

there is, I`ve seen whats known in the UK as "Drizzle" and that makes very fine snow when it hits a cold wind in opposite direction at ground level, then there seems to be an upper level activity where it`s not so cold at ground but is higher up and srandard rain drops turn into sleet (I`m no meteorologist and so don`t know all the correct terms), then there`s theres the HUGE chicken egg sized snow "flakes" (probably a whole bunch stuck together I think) that seem to fall slowly, mega snow we call em here in this house, those are the cool ones to watch

 

but "TOO cold to snow", well, as you pointed out, there has to be alot more to it than just temperature

[rockstarjaiden]

smart people really intrigue me...

[JaKiri]

YT2095 said in post # :

now I`m thinking of the north or South pole here the temp is often -20 or lower and it`s like snowing all the time there! so what`s this "It`s too cold to snow" business all about?

 

It's not snowing.

 

The north and south poles are strictly speaking deserts, due to the immensely small amount of precipitation.

 

The blizzarding effect if just loose snow being blown about.

[mossoi]

Here's a coincidence. About 3 minutes after I submitted that last post we had a sudden, brief blizzard here. It's not snowed around here for around 5 years and this was a full blown, can't see your hand in front of your face, flurry.

 

If I wasn't a scientist I'd say that psychic meteorological powers were reading the forum over my shoulder.

 

I guess it was warm enough to snow

[YT2095]

I`ll go to any lengths to prove a point LOL

[rockstarjaiden]

wicked