My NSX, too fast??

[Smoothaccel]

about the ice crystals and due point not the cold tyres


Originally posted by nsxtasy:
Moisture doesn't condense out of the atmosphere onto solid surfaces unless the humidity is close to 100 percent - whether the temperature is below freezing or above freezing
Depends how you look at it. For example: If you pull a cold bottle out of your fridge and place it in a room, moisture will condense onto the bottle regardless of the relative humidity in the room (assuming it is not 0). Reason: although the room is not at 100% "relative humidity", the air around the bottle cools down to the temperature where there is 100% saturation and droplets form on the chilled bottle. The point: for ice crystals to form on pavement, the pavement must be cold enough to lower the temperature of the air, flowing over it, to the point where it's relative humidity reaches 100% and ofcourse below freezing for ice crystals.

Originally posted by nsxtasy:
One way of determining whether humidity will condense on the ground is to look at the difference between the temperature and the dewpoint. The dewpoint is the temperature at which the humidity would be 100 percent with the then-current amount of humidity in the air. If the temperature is close to the dewpoint, then moisture will condense on the ground (as dew if it's above freezing) and, if it's below freezing, in the air as snow. If the temperature is not close to the dewpoint, then moisture won't condense.

Kinda confusing but some truth. key is the difference in temperature of the air and the surface not air and dew point and the air has to drop its temperature where it cannot hold the moisture it onced carried. Hot air has the pontential to hold more moisture. And,its relative humidity.
That said, who knows exactly all the conditions that day.

 

[nsxtasy]

Smoothaccel,

While it's possible for moisture to condense on the road surface and for ice to form that way, this is not very common, and would only happen with a fairly unusual combination of atmospheric conditions. Moisture usually condenses out of the air when temperatures are dropping, because colder air cannot hold as much moisture as warmer air. This is why dew forms overnight, as temperatures cool, and goes away in the morning as temperatures warm.

In the winter, the pavement temperature usually stays slightly warmer than the air above it. When the air temperature is 30 degrees F, as in nsx4fun's example, the roads generally don't freeze at all; they only accumulate moisture if snow falls on them. At colder temperatures (below 25 F) ice can form on the roads, but it commonly forms from precipitation (rain or snow) that re-freezes, not from condensation. When there has been no precipitation, the roads are usually dry. However, if there is enough humidity in the air for moisture to condense - in other words, close to 100 percent humidity - then it condenses in the air as snow (precipitation), and this is what makes the roads wet.

And moisture certainly does not automatically condense from the air when the temperature goes below freezing, unless the humidity is close to 100 percent. Which, unless it's snowing, it isn't.

Originally posted by Smoothaccel:
for ice crystals to form on pavement, the pavement must be cold enough to lower the temperature of the air, flowing over it, to the point where it's relative humidity reaches 100% and ofcourse below freezing for ice crystals.

That's correct - and that's why ice rarely condenses on pavement - because the pavement is rarely significantly colder than the air above it. On those rare occasions that conditions are right for this - relatively humid air and air temperatures that drop fast - snow is likely to be falling on the ground so you don't even notice condensation on the pavement.

[This message has been edited by nsxtasy (edited 04 March 2003).]

 

[SNDSOUL]

Not that I know anything about how the atmosphere works, I can say that it is always 100% humidity here on the coast of Mississippi and occasionally gets in the twentys, but it never snows and I cant think of any instance when ice formed on the roads. What that means for your debate I dont know, just thought I'd throw in my .02

 

[nsxtasy]

What's common in a lot of parts of the South is freezing rain - rain when air temperatures are in the twenties or colder, which freezes on the pavement and ices the roads and makes them treacherous. I know this is fairly common in Atlanta and the Carolinas during the winter. It happens here every once in a great while (perhaps once every 5-10 years).

 

[BostonNSX]

No problem
gimme a call and a check strip ur go fast car parts ship them to me.. I can get your problem all set .

Originally posted by pbassjo:
My car is too fast. I make too much money.
My wife's too beautiful. The list goes on.
I guess we are here just to suffer.

 

[randall]

Originally posted by matteni:
it is not like stepping into a Hemming Viper with NOS or something.

what is a Hemming Viper?no such car.

 

[Lud]

Everything you ever wanted to know about frost formation: http://www.suite101.com/article.cfm/13646/83233

Back to topic?

 

[nsxtasy]

Originally posted by Lud:
Back to topic?

There's a concept!

Originally posted by Periokid:
I'd never thought I'd ever say something like "it has too much power".

What's the expression? "You can never be too rich, or too thin... or have too much power. Oorgh! Oorgh! Oorgh!" - Tim Allen

 

[mason@tirerack]

ZOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOM!


------------------
Mason
Tire Rack sales...contact me for all your wheel and tire needs.
1-800-428-8355
Ext. 619

1991 Acura NSX (auto)