Progression of Clouds During the Passage of a Warm Front.
The following video was taken from the roof of the Science Building (Bob Wright Centre) at the University of Victoria, in Saanich, BC. The camera looks (approximately) north.
The progression of cloud types throughout the course of the day suggests a slow moving, wedge shaped, warm front pushing in from the west. Typically the progression is Ci, Cs, As, Ns, St.
- Ci: cirrus 11:30
- Cs: cirrostratus 14:00
- As: altostratus (maybe) 16:30
- Ns: nimbostratus, also at 16:30, you can see the fall streaks
- St to Sc: Stratus to Stratocumulus, late in the day and the following night (we had showers over greater Victoria early in the morning of the following day.
Included below is an image showing the progression of cloud types a stationary observer typically sees with the passage of a warm front. The warm front is slowly pushing a colder air mass (to the left here, to the east, the right, in the case of the video).
The image is from Moran, J.M. and Morgan, M.D., Meteorology and the Science of Weather, Maxwell MacMillan Canada, Toronto, 1994.