Consider

James___ wrote: Mountains are known to increase atmospheric air pressure on the windward side.

James___ wrote:
Mountains are known to increase atmospheric air pressure on the windward side. Typically speaking, warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side.

IBdaMann wrote:

James___ wrote: Mountains are known to increase atmospheric air pressure on the windward side.

Could you elaborate on this point?

Mountains are not known for increasing atmospheric pressure.

.

Into the Night wrote:Actually, they do...on the leeward side (surface pressure).

IBdaMann wrote:

Into the Night wrote:Actually, they do...on the leeward side (surface pressure).

That's kind of why I was asking for clarification.

Mountains don't cause a change in atmospheric pressure.

Differences in windspeed cause difference in pressure. It's why wings work and why airplanes can fly.

Otherwise the existence of a mountain does not itself change atmospheric pressure.

.

Into the Night wrote:

James___ wrote:
Mountains are known to increase atmospheric air pressure on the windward side. Typically speaking, warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side.

You have it backwards.

Spongy Iris wrote:

Into the Night wrote:

James___ wrote:
Mountains are known to increase atmospheric air pressure on the windward side. Typically speaking, warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side.

You have it backwards.

We had 4 freezing mornings Nov, 9, 28, 29, 30 where temps reached the low 30s.

We are less than 10 miles south of Mt Diablo summit (not considering winding road which is a longer drive).

Our elevation less than 500 ft, Mt Diablo elevation more than 3800 ft.

I checked the lows on Mt Diablo for those freezing mornings, and they were consistently around 10 degrees higher than us, with lows in the 40s.

The weather was slightly cloudy at the summit and clear on the ground. Indeed the atmospheric pressure appears to have been higher at the summit than on the ground on these cold days.

Into the Night wrote:

Spongy Iris wrote:

Into the Night wrote:

James___ wrote:
Mountains are known to increase atmospheric air pressure on the windward side. Typically speaking, warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side.

You have it backwards.

We had 4 freezing mornings Nov, 9, 28, 29, 30 where temps reached the low 30s.

We are less than 10 miles south of Mt Diablo summit (not considering winding road which is a longer drive).

Our elevation less than 500 ft, Mt Diablo elevation more than 3800 ft.

I checked the lows on Mt Diablo for those freezing mornings, and they were consistently around 10 degrees higher than us, with lows in the 40s.

The weather was slightly cloudy at the summit and clear on the ground. Indeed the atmospheric pressure appears to have been higher at the summit than on the ground on these cold days.

Clouds are not pressure.
Temperature is not pressure.

Spongy Iris wrote:

Into the Night wrote:

Spongy Iris wrote:

Into the Night wrote:

James___ wrote:
Mountains are known to increase atmospheric air pressure on the windward side. Typically speaking, warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side.

You have it backwards.

We had 4 freezing mornings Nov, 9, 28, 29, 30 where temps reached the low 30s.

We are less than 10 miles south of Mt Diablo summit (not considering winding road which is a longer drive).

Our elevation less than 500 ft, Mt Diablo elevation more than 3800 ft.

I checked the lows on Mt Diablo for those freezing mornings, and they were consistently around 10 degrees higher than us, with lows in the 40s.

The weather was slightly cloudy at the summit and clear on the ground. Indeed the atmospheric pressure appears to have been higher at the summit than on the ground on these cold days.

Clouds are not pressure.
Temperature is not pressure.

Why don't you explain why it was not as cold at the top of mountain than at the bottom of the mountain, instead of deflecting with word games?

Into the Night wrote:

Spongy Iris wrote:

Into the Night wrote:

Spongy Iris wrote:

Into the Night wrote:

James___ wrote:
Mountains are known to increase atmospheric air pressure on the windward side. Typically speaking, warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side.

You have it backwards.

We had 4 freezing mornings Nov, 9, 28, 29, 30 where temps reached the low 30s.

We are less than 10 miles south of Mt Diablo summit (not considering winding road which is a longer drive).

Our elevation less than 500 ft, Mt Diablo elevation more than 3800 ft.

I checked the lows on Mt Diablo for those freezing mornings, and they were consistently around 10 degrees higher than us, with lows in the 40s.

The weather was slightly cloudy at the summit and clear on the ground. Indeed the atmospheric pressure appears to have been higher at the summit than on the ground on these cold days.

Clouds are not pressure.
Temperature is not pressure.

Why don't you explain why it was not as cold at the top of mountain than at the bottom of the mountain, instead of deflecting with word games?

A temperature inversion. It happens from time to time, usually when a warm front is passing through. I am not playing word games.

Spongy Iris wrote:

Into the Night wrote:

Spongy Iris wrote:

Into the Night wrote:

Spongy Iris wrote:

Into the Night wrote:

James___ wrote:
Mountains are known to increase atmospheric air pressure on the windward side. Typically speaking, warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side.

You have it backwards.

We had 4 freezing mornings Nov, 9, 28, 29, 30 where temps reached the low 30s.

We are less than 10 miles south of Mt Diablo summit (not considering winding road which is a longer drive).

Our elevation less than 500 ft, Mt Diablo elevation more than 3800 ft.

I checked the lows on Mt Diablo for those freezing mornings, and they were consistently around 10 degrees higher than us, with lows in the 40s.

The weather was slightly cloudy at the summit and clear on the ground. Indeed the atmospheric pressure appears to have been higher at the summit than on the ground on these cold days.

Clouds are not pressure.
Temperature is not pressure.

Why don't you explain why it was not as cold at the top of mountain than at the bottom of the mountain, instead of deflecting with word games?

A temperature inversion. It happens from time to time, usually when a warm front is passing through. I am not playing word games.

Is that not the same thing as the following statement which you just denied?

"warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side."

GasGuzzler wrote:

Spongy Iris wrote:

Into the Night wrote:

Spongy Iris wrote:

Into the Night wrote:

Spongy Iris wrote:

Into the Night wrote:

James___ wrote:
Mountains are known to increase atmospheric air pressure on the windward side. Typically speaking, warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side.

You have it backwards.

We had 4 freezing mornings Nov, 9, 28, 29, 30 where temps reached the low 30s.

We are less than 10 miles south of Mt Diablo summit (not considering winding road which is a longer drive).

Our elevation less than 500 ft, Mt Diablo elevation more than 3800 ft.

I checked the lows on Mt Diablo for those freezing mornings, and they were consistently around 10 degrees higher than us, with lows in the 40s.

The weather was slightly cloudy at the summit and clear on the ground. Indeed the atmospheric pressure appears to have been higher at the summit than on the ground on these cold days.

Clouds are not pressure.
Temperature is not pressure.

Why don't you explain why it was not as cold at the top of mountain than at the bottom of the mountain, instead of deflecting with word games?

A temperature inversion. It happens from time to time, usually when a warm front is passing through. I am not playing word games.

Is that not the same thing as the following statement which you just denied?

"warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side."

Not the same thing.

James is trying to describe compressional heating, but he's all a mess.

A warm front will tend to have the warm air ride up over top of the cooler air at the surface. The cooler air is more dense and the warmer cannot immediately displace the cooler air. This is called a temperature inversion because it is backwards from typical airmasses that are cooler with height.

Compressional heating is quite something when wind conditions are right. As cooler air is forced down the mountain slopes, it is compressed and warmed. I have experienced 70 degree Iowa weather in February due to compressional heating off the Rockies. Average Iowa Feb temp is 30-35F, so it is always welcome here in the winter.

James___ wrote:

GasGuzzler wrote:

Spongy Iris wrote:

Into the Night wrote:

Spongy Iris wrote:

Into the Night wrote:

Spongy Iris wrote:

Into the Night wrote:

James___ wrote:
Mountains are known to increase atmospheric air pressure on the windward side. Typically speaking, warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side.

You have it backwards.

We had 4 freezing mornings Nov, 9, 28, 29, 30 where temps reached the low 30s.

We are less than 10 miles south of Mt Diablo summit (not considering winding road which is a longer drive).

Our elevation less than 500 ft, Mt Diablo elevation more than 3800 ft.

I checked the lows on Mt Diablo for those freezing mornings, and they were consistently around 10 degrees higher than us, with lows in the 40s.

The weather was slightly cloudy at the summit and clear on the ground. Indeed the atmospheric pressure appears to have been higher at the summit than on the ground on these cold days.

Clouds are not pressure.
Temperature is not pressure.

Why don't you explain why it was not as cold at the top of mountain than at the bottom of the mountain, instead of deflecting with word games?

A temperature inversion. It happens from time to time, usually when a warm front is passing through. I am not playing word games.

Is that not the same thing as the following statement which you just denied?

"warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side."

Not the same thing.

James is trying to describe compressional heating, but he's all a mess.

A warm front will tend to have the warm air ride up over top of the cooler air at the surface. The cooler air is more dense and the warmer cannot immediately displace the cooler air. This is called a temperature inversion because it is backwards from typical airmasses that are cooler with height.

Compressional heating is quite something when wind conditions are right. As cooler air is forced down the mountain slopes, it is compressed and warmed. I have experienced 70 degree Iowa weather in February due to compressional heating off the Rockies. Average Iowa Feb temp is 30-35F, so it is always welcome here in the winter.

In the winter when the wind goes over a mountain, it won't compress on the leeward side.

GasGuzzler wrote:

James___ wrote:

GasGuzzler wrote:

Spongy Iris wrote:

Into the Night wrote:

Spongy Iris wrote:

Into the Night wrote:

Spongy Iris wrote:

Into the Night wrote:

James___ wrote:
Mountains are known to increase atmospheric air pressure on the windward side. Typically speaking, warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side.

You have it backwards.

We had 4 freezing mornings Nov, 9, 28, 29, 30 where temps reached the low 30s.

We are less than 10 miles south of Mt Diablo summit (not considering winding road which is a longer drive).

Our elevation less than 500 ft, Mt Diablo elevation more than 3800 ft.

I checked the lows on Mt Diablo for those freezing mornings, and they were consistently around 10 degrees higher than us, with lows in the 40s.

The weather was slightly cloudy at the summit and clear on the ground. Indeed the atmospheric pressure appears to have been higher at the summit than on the ground on these cold days.

Clouds are not pressure.
Temperature is not pressure.

Why don't you explain why it was not as cold at the top of mountain than at the bottom of the mountain, instead of deflecting with word games?

A temperature inversion. It happens from time to time, usually when a warm front is passing through. I am not playing word games.

Is that not the same thing as the following statement which you just denied?

"warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side."

Not the same thing.

James is trying to describe compressional heating, but he's all a mess.

A warm front will tend to have the warm air ride up over top of the cooler air at the surface. The cooler air is more dense and the warmer cannot immediately displace the cooler air. This is called a temperature inversion because it is backwards from typical airmasses that are cooler with height.

Compressional heating is quite something when wind conditions are right. As cooler air is forced down the mountain slopes, it is compressed and warmed. I have experienced 70 degree Iowa weather in February due to compressional heating off the Rockies. Average Iowa Feb temp is 30-35F, so it is always welcome here in the winter.

In the winter when the wind goes over a mountain, it won't compress on the leeward side.

I suppose your going to tell me that in the winter it must conserve its heat energy until it can become east coast waste heat. Am I close?

Spongy Iris wrote:

Into the Night wrote:

Spongy Iris wrote:

Into the Night wrote:

Spongy Iris wrote:

Into the Night wrote:

James___ wrote:
Mountains are known to increase atmospheric air pressure on the windward side. Typically speaking, warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side.

You have it backwards.

We had 4 freezing mornings Nov, 9, 28, 29, 30 where temps reached the low 30s.

We are less than 10 miles south of Mt Diablo summit (not considering winding road which is a longer drive).

Our elevation less than 500 ft, Mt Diablo elevation more than 3800 ft.

I checked the lows on Mt Diablo for those freezing mornings, and they were consistently around 10 degrees higher than us, with lows in the 40s.

The weather was slightly cloudy at the summit and clear on the ground. Indeed the atmospheric pressure appears to have been higher at the summit than on the ground on these cold days.

Clouds are not pressure.
Temperature is not pressure.

Why don't you explain why it was not as cold at the top of mountain than at the bottom of the mountain, instead of deflecting with word games?

A temperature inversion. It happens from time to time, usually when a warm front is passing through. I am not playing word games.

Is that not the same thing as the following statement which you just denied?

"warmer, drier air will rise and move to the leeward side (think of thermals on a larger scale). This in turn can lower the temperature and dew point at ground level on the windward side."

James___ wrote:
If you look at the wind going over the Sierra Nevada and then the Rocky Mountains, notice how it's trending south where it's warmer? Not conserving heat content. It's looking for it and it's right there in the map.
And if you look closely, with Oregon, it's the Cascades and then rides the Rocky Mountains south. I think everyone knows that Pie Town, New Mexico is on the continental divide.
Take some time to see how wind that passes over mountains heads towards warmer climates or at least where there's more solar radiation.

HarveyH55 wrote:
Except... Florida don't have any mountains, and we are a good piece from Canada. No good damn reason for it to get down in the 30s and 40s in Florida.

HarveyH55 wrote:
Except... Florida don't have any mountains, and we are a good piece from Canada. No good damn reason for it to get down in the 30s and 40s in Florida.

Into the Night wrote:

HarveyH55 wrote:
Except... Florida don't have any mountains, and we are a good piece from Canada. No good damn reason for it to get down in the 30s and 40s in Florida.

It happens from time to time during a winter. Apparently this one was caused by a cold front that is moving through. It won't last long. Soon you'll be back to your usual sunny self!

James___ wrote:

HarveyH55 wrote:
Except... Florida don't have any mountains, and we are a good piece from Canada. No good damn reason for it to get down in the 30s and 40s in Florida.

Barometric pressure is lower than usual. Look inside the red circle. Air pressure is 1012 millibars. Why it cools at night.

And if anyone notices, high pressure systems are moving into the MidWest.