NASA’s EOSDIS Worldview gives stunning pictures. This one, of polar regions north of Greenland appears to show the ice edge with cold air streaming off over the sea forming ever deepening cumulus. This edge seems almost too bold.
Check on MODIS (Dundee) Channel 6 (snow/cloud discrimination 1628-1652nm) and Channel 22 (surface cloud 3.929-3.989µm) seems to back this analysis up; temperatures of cloud tops over the sea being colder than the ice. Fractures and polynyas in ice, much loved by cold war submariners, show up with amazing clarity.
desert sands blow out of Africa on a conveyor belt of air ahead of a cold front
Cold fronts are normally identifiable from their cloud signature on satellite imagery. Of course, air mass boundaries can exist without condensation: density changes and air flows can exist without clouds particularly in dry and hot air. Summer front can cross the UK with just low strato-cumulus. In the Mediterranean, cloudless density boundaries one day give potential for fierce thunderstorms the next.
The 23 Mar 2016 was a case in point. Over the Eastern Mediterranean we note a conveyor belt of air dragging sand northwards from the African deserts. No clouds but a cold front none the less.