Clouds hang together, smoke disperses

water vapour doesn’t seem to disperse like smoke does. Clouds are in the bluish part of the field and everything else is smoke. I think it has to do with the difference between a gas and an aerosol, but I want to know what people with a background in weather think.

I think the primary difference is that clouds form in place and in equilibrium with their surroundings whereas smoke comes streaming up from a fixed point.

Clouds of all possible forms and air containing dust, smoke etc are both aerosols.

If the temperature of humid air (a gas mix) descends below its dew point, it becomes an aerosol, consisting of saturated air and tiny water droplets ore ice crystals.

The temperature may descend by thermal radiation into the upper atmosphere; the result at ground level will be fog.

On the other hand, a small or large upwind cools the air, by 0.6° to 1°C per 100 meters of uplift; there will be small or large clouds.

This is an inherent phenomenon of the local air masses, relative and absolute humidity and loss of temperature. Clouds cannot expand laterally; they are limited to the dimensions of their upwind.

An obvious example is within a hurricane:
Around the eye is a thick and large layer of clouds; there, the air aspired from outside has a strong ascending movement. Inside the cloudless eye, dry air from the stratosphere is descending.

Aerosols with smoke, dust etc. are not inherent to the air masses. They have an external source and dilute in the air currents, or fall back.

However, are you sure, that the cloud cover in the foreground of your pic is smoke?

In an airplane, I rarely look outside, but I could imagine seeing the top of an occluded front in the foreground, and behind, the following cold air mass with its isolated clouds…

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They sure look like clouds to me.

In the bay when the tide changes, islands grow or shrink, appear and disappear The shape and structure of the land isn’t changing, it’s just being made visible by a changing parameter, the water level.

LIkewise clouds appear and disappear, grow or shrink with changes in the saturation point. As the shoreline of an island is defined by sea level so are the edges of a cloud defined by water vapor, made visible at the saturation point.


These lenticular clouds over Mt. Rainier have hard saturation edges and appear stationary but air is rushing over the top at a good clip.


I’m very sure that it’s smoke. In Vancouver you can’t see across Burrard Inlet, the air is hazy if you try to see more than a block, in the mountains triathlons and flights have been cancelled. But I will try to convince you.

Did it work?

I think this picture illustrates what you-all are telling me about clouds. They form where they must form and stay where their right conditions are (above the ranges in this case) while the smoke just does its brownian motion thing.

Also @Kennebec_Captain , I had no idea you were a poet.

The weather poet. Vera nice.



Rainier’s brother: I think this is Mount Baker, with Shuksan peaking out beside in all that smoke.

This is two days ago, photo from NASA

Here showing the aerosol index


From NWS Gray Maine discussion of today’s weather:

.Quiet day under building high pressure. With the exception of the smoke plume evident on GOES visible imagery that will provide a hazy milky appearance to the sky…another fair and warm summer day in progress across the region.

Prev disc… 630am update… Red sky in the morning, smoke take warning? This morning clear skies are being interrupted by a high level haze of smoke from the western forest fires resulting in a bright red sunrise. Along with the [smoke](
/glossary.php?word=smoke) we have some fog in the Connecticut river valley that will begin to dissipate in the next hour.

Clear day with no clouds but the sky does have a hazy milky appearance.

Reminded me of a classic quote from them, long ago:

This is the National Weather Service in Gray, Maine. Here is the experimental hay drying forecast for the covered area. Today’s hay drying condition is wetting.

Check this out. Smoke from west coast fire seen over the Northeast. Also, NOAA Satellites is one of my favorite follows on Twitter. The new GOES satellites they have are incredible.

#Smoke from the western U.S. and Canadian #wildfires has traveled across the continent all the way to New England. Check out the smoky haze #GOESEast is seeing over #Maine today.

— NOAA Satellites (@NOAASatellites) August 24, 2018

Here’s something on the aerosol display and what sort of particles are involved.

NASA link

Interesting the bands of sea salt traversing the Southern Ocean.


Today, the smoke of British Columbia’s wildfires arrived in continental Europe.
The meteorologists say, it took the jet stream to cross the Atlantic…

Our sky is cloudless, but high above, there is some milky dust.

Wow! That’s an enormous image, 8000x4000 px. Can almost see my house on it.

Some years ago, some scientists in Italy tried to find salt on the snow covered southern slopes of the Alps (north of Milan and Torino)…
Indeed they where looking for remnants of the bad salt strewn on the alpine roads…

Far above the roads (>2500 m of altitude), they discovered salty snow, and were perplexed.

Analysis of the salt proved the Mediterranean origin. Heavy Sirocco winds, from the Sahara northwards to the Alps makes breaking waves on the Mediterranean. The wind takes the salty foam atop the waves and transports the salt up into the mountains!

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The day the sky here was milky white, that evening the moon came up orange. Next day the skies returned to blue.