Clouds of the Day - A Stratus Kind of Day

It is a stratus kind of day. After sharp lightning before midnight but only a trace of rain here and .04” at the Waterloo Airport only a couple of miles away, this is what the sky looked like at 9:30 AM. Stratus is a sheet-like cloud with a mostly uniform base. By this time the base was already showing a few rounded bottoms suggesting the formation clouds resembling cumulus. It is really a mixture of stratus and cumulus so the name is stratocumulus.

As temperatures warm during the day we can expect the cloud base to reveal breaks and the cloud base to rise into the mid-levels above 6,000 feet (2000 m).

As low level temperatures slowly warm mixing of the atmosphere begins to lower the relative humidity. At 1:00 PM we see the mid-level base of altostratus and altocumulus. There is even a hint of blue sky.

A close-up at 1:00 PM reveals the darker bases of altocumulus and a few lower cumulus. There are even a few ragged mid-level altocumulus floccus - tufts of wool. The mixing of the air allows drier air in the lower levels to mix with the air where the stratus has formed. The mixing lowers the relative humidity which breaks the cloud base open to reveal blue sky raise the cloud ceilings and change the cloud type.