Basic Weather question

[LewisU_Pilot]

This may be a stupid question, but could it get cold enough where if the current conditions were able to produce perception it would not be able to? Say negative 40 would snow still fall?

My GF seems to think at 0 degrees there is a less likely chance of precip than at 30. I am trying to tell her it has nothing to do with temp. The temp only changes the type of precip such as sleet,snow,rain. She does not believe me.

 

[philo beddoe]

The colder air is, the less moisture it can hold. Therefore, even as the air chills down, there is so little moisture to precipitate out that snow is unlikely.

At very cold temps you can get ice crystals, but that is about it. This is why carburetor ice is more likely at warmer OATs. The warmer air hold more moisture, and when it cools in the venturi, you get a lot of vapor precipitating out. If the venturi temp drops to 0 degrees C, you get carb ice.

As OAT drops, there is less moisture in the air, so carb ice can happen, but prbably in smaller amounts.

 

[LewisU_Pilot]

The colder air is, the less moisture it can hold. Therefore, even as the air chills down, there is so little moisture to precipitate out that snow is unlikely.

At very cold temps you can get ice crystals, but that is about it. This is why carburetor ice is more likely at warmer OATs. The warmer air hold more moisture, and when it cools in the venturi, you get a lot of vapor precipitating out. If the venturi temp drops to 0 degrees C, you get carb ice.

As OAT drops, there is less moisture in the air, so carb ice can happen, but prbably in smaller amounts.

Boy do i feel dumb
thanks for the info... U learn something new everyday.

 

[Pilot124]

Sucks when the Girlfriend is right huh. You will never hear the end of it from her.

 

[fr0g]

I wouldn't give up so quickly. It depends on exactly what temperature you are talking about.. surface temperature? The temperature where the precip forms??
I mean, you could have a cold airmass overrun with a warmer, moist airmass and that would produce snow like no other. Still, it would be very cold on the ground.
Although I must admit snow is rare below about 10 degrees or so, like the above posters mentioned.

 

[minitour]

Sucks when the Girlfriend is right huh. You will never hear the end of it from her.

unless she won't figure it out and you just tell her she was wrong...

-mini

 

[Bernoulli]

This may be a stupid question, but could it get cold enough where if the current conditions were able to produce perception it would not be able to? Say negative 40 would snow still fall?

It all really depends on the relative humidity. Just as a previous post mentioned, if a cold airmass overtook a warm moist (high humidity) airmass then ya... it's going to rain or snow or sleet or freeze depending on how cold the cold airmass is... but... a cold airmass will eventually squeeze out all that moisture and the airmass will then have low humidity and there will no longer be any precip. Think of Colorado on a cold winter day when the weather is good... the air is very dry so ya put on the chap stick cause your skin & lips get dry. There is not enought moisture in the air to squeeze out, or in other words, the humidity is low.

 

[labbats]

unless she won't figure it out and you just tell her she was wrong...

-mini

I was thinking the same thing.

 

[EagleRJ]

There is indeed a temperature below which precipitation isn't possible. I don't remember exactly where it is, but it's down around -20F. Falling precipitation- both rain and snow- requires accretion (particles clumping together and growing bigger). That requires at least some liquid water content. Below about -20F, the atmosphere doesn't support much water anyway, and what water there is is completely frozen.

When it's extremely cold (-30F and below), you'll get stuff like ice crystals and ice fog. Nothing is actually accumulating, but you can see the ice crystals sparkling as they float through the air.

 

[illinipilot]

Dude,

What is your instructor teaching you anyway?

JF

 

[LewisU_Pilot]

Dude,

What is your instructor teaching you anyway?

JF

Good question.. He ditched me to go work at airnet..

Dude whats up man? Do you still have the same cell number? Been meaning to call to catch up but been busy and figured Id leave you alone during your training.