Have a look at Loops and Overlays and decide whether the cases are Waves or Upper Waves.
Wave
Upper Wave
12 February 2004
Meteosat IR image
Loop 10.00 UTC - 12.00 UTC
Key Parameters
16 December 2003
Meteosat IR image
Loop 09.00 UTC - 12.00 UTC
Key Parameters
Back to Wave - Separation Exercise