4. Mammatus "clouds boiling upside down", on top of a flanking down draft.
Mammatus, also known as mammatocumulus (meaning "mammary cloud"),
is a meteorological term applied to a cellular pattern of pouches hanging
underneath the base of a cloud.
5. Massive single cell severe tornadic thunderstorm.
6. Downdraft of precipitation from a young cumulonimbus cloud.
The initial downrush happening as the rest of cell is still forming and building.
7. Leading edge of a flanking downdraft of a thunderstorm.
8. Another great mammatus – extremely unstable air.
9. Sunset on dissipating thunderstorms.
Could have two cells rotating in opposite directions, rare,
but meteorologically possible, like two egg beaters.
10. Sunset dissipating thunderstorm.
11. Volcanic eruption creating a circular outflow boundary.
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