Clouds of the Day - Wednesday, May 3, 2023
/Today started with spectacularly clear skies and ended with an even more spectacular sunset. This was the first time all week that clouds appeared in our sky. What a view it was this evening. Check out the clouds and the colorful yellow sunset. The yellow tint to the sky was courtesy of very dry air - 25% relative humidity - and dust particles that screened out all but the yellow hues as the Sun approached the horizon for sunset.
Note the various cloud types that formed overhead this evening. The cloud streaks were bands of Altostratus and Altocumulus clouds. There were also pillow-like Altocumulus and wave type clouds caused by gravity waves rippling through the air overhead.
Photo copyright May 3, 2023 by Craig johnson
Photo copyright May 3, 2023 by Craig johnson
The clouds above were visible directly overhead. We are looking at fall streaks (also called virga) which were ice crystals condensing in the cold air aloft and descending into the drier air below where they sublimated. Sublimation is the term for ice crystals changing from crystals directly to invisible water vapor. Now you see it and now you don’t.
Photo copyright May 3, 2023 by Craig johnson
The sunset was vivid this evening. The yellow glowed brightly in the west.
Photo copyright May 3, 2023 by Craig johnson
When watching clouds practice looking for detail in the cloud formations. The above photo is labelled to help you notice some common patterns we see throughout the year.
Photo copyright May 3, 2023 by Craig johnson
One final look at sunset this evening. Views on the prairie can be spectacular because the wide open spaces allow for maximum visibility in the fresh air outdoors.
The yellow sunset indicated dry air to the west over the Great Plains but it was dry here too. The dew point trace on our weather station shows the relative humidity (blue line and right-hand scale) dropping to 19% around 4:00 p.m. CDT. Notice the relationship between the relative humidity and the temperature (red line). As the temperature rises and the dew point changes little, the dew point drops. It reaches it’s low point during the day when the temperature reaches its maximum. Then as the temperature cooled in the late afternoon and evening the relative humidity began to rise.