M4 Clouds M4 Clouds - Symbol = Flying Saucer. Lenticular altocumulus showing remarkable symmetry. Wind flows through this stationary cloud. Lenticular Clouds Lenticular altocumulus clouds resemble flying saucers in the sky. They also look like a concentric stack of different sized pancakes. Source: ********************************************* National Weather Service Air that moves over mountainous regions will M4 Clouds: Altocumulus (Ac) continually often form slow moving lenticular clouds. The changing shape clouds are often thin, but well defined. The clouds are usually also confined to a smaller M4 area and do not invade the sky although their Patches (often in the form of almonds or formation can extend downwind 100 km fish) of altocumulus, the greater part of away from a mountainous area. which is semi-transparent; the clouds occur Source: at one or more levels and the elements are continually changing in appearance. Notes: These clouds often appear to be dissolving in some places and forming in others. These clouds are usually thin and do not progressively invade the sky. They often resemble a net or honeycomb. They also often form in patches in the shape of almonds or lenses called Altocumulus Lenticularis (ACSL) or wave clouds. These formations are caused by wave motions in the atmosphere and are frequently seen in mountainous or hilly areas. They may be triggered off by hills only a few thousand feet high and may extend down wind for over 60 miles (100 km).The cloud elements form at the windward edge of the cloud and are
M4 Clouds Flying Saucer. Lenticular altocumulus showing remarkable symmetry. Wind flows through this stationary cloud. Source: ********************************************* M4 Clouds: Altocumulus (Ac) continually changing shape M4 Patches (often in the form of almonds or fish) of altocumulus, the greater part of which is semi-transparent; the clouds occur at one or more levels and the elements are continually changing in appearance. Notes: These clouds often appear to be dissolving in some places and forming in others. These clouds are usually thin and do not progressively invade the sky. They often resemble a net or honeycomb. They also often form in patches in the shape of almonds or lenses called Altocumulus Lenticularis (ACSL) or wave clouds. These formations are caused by wave motions in the atmosphere and are frequently seen in mountainous or hilly areas. They may be triggered off by hills only a few thousand feet high and may extend down wind for over 60 miles (100 km).The cloud elements form at the windward edge of the cloud and are M4 Clouds - Symbol = Lenticular Clouds Lenticular altocumulus clouds resemble flying saucers in the sky. They also look like a concentric stack of different sized pancakes. National Weather Service Air that moves over mountainous regions will often form slow moving lenticular clouds. The clouds are often thin, but well defined. The clouds are usually also confined to a smaller area and do not invade the sky although their formation can extend downwind 100 km away from a mountainous area. Source:
APPENDICES-2.docx