Sunday, February 14, 2016

#1717 "Sunset Waves Nite"

I thought that I should explain what I saw and painted... you can stop reading at any point when it becomes boring...

A winter storm was approaching Singleton Lake. The large arch of the deformation zone marched steadily from the western horizon. The warm conveyor belt must have been especially warm as it created a significant stable layer that in turn generated gravity wave clouds. Even though the storm was steadily advancing northeastward, the winds in the atmosphere frame of reference were perpendicular to the gravity waves. The clouds looked like a zipper, unzipping. I guess this was unusual enough for me to want to record this in oils. The night was fast approaching and it would soon be dark. I made a few notes so I could paint this on another day.

This is a very interesting deformation zone. I believe that the atmosphere relative winds were northwesterly perpendicular to the gravity waves. At the time I should have watched which way those clouds were moving. This means that the col of the deformation zone was thus further to the northwest. This has the implication that the thrust of the system would be over northeastern Ontario and not over Singleton Lake. The anticyclonic minimum was causing the deformation zone to curl anticyclonically. This diagnosis was also consistent with the thinner cloud layers in the warm conveyor belt of the approaching system.

The zipper pattern in the gravity waves was caused by a slight convergence in the system relative winds with the point of the zipper identifying the convergence line and slightly strong winds. The reverse is also true when the zipper is pointing upwind or upstream.

The setting sun was illuminating higher and more distant cirrostratus along the horizon. This is consistent with the katabatic or inactive nature of this warm front with less cloud along the leading upper edge. The setting sun was setting this cirrostratus on fire. This cloudy fire was reflected in the open water of Jim Day Rapids. The snow on the ice of Singleton Lake was not nearly as good a mirror as the calm water.

These are the kind of thoughts you can have when you have time to sit and reflect, so to speak, on the lessons that the clouds tell. The bottom line was that Singleton Lake was going to get into the warm sector of the approaching storm. A bit of a thaw was on the way. Meanwhile, northeastern Ontario would receive the brunt of the storm with freezing rain, snow and otherwise wintry weather. The cold front would come through in a day or two and bring winter back to Singleton - as it should be.

Note that the bands of cirrostratus convert to cirrocumulus on the opposite side of the deformation zone. It is a different air mass with a different characteristics on the other side of the deformation zone. The drier air was more unstable. Note also that in the atmosphere everything happens in waves at regular intervals. The meteorological processes are more of a ballet with everything in perfect balance.

The title focuses on the idea that the sun was waving good night as it exited below the western horizon. The clouds are the only way that the atmosphere can communicate, so to speak. "Nite" is just an informal, simplified spelling of night and I wanted something different in order to keep my titles unique.

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