what is this cloud about?
It is generally characterized by thin, wispy strands, giving the type its name from the Latin word "cirrus", meaning a ringlet or curling lock of hair
Cirrus cloud
Cirrus (cloud classification symbol: Ci) is a genus of atmospheric cloud generally characterized by thin, wispy strands, giving the type its name from the Latin word "cirrus", meaning a ringlet or curling lock of hair. Such a cloud can form at any altitude between above sea level. The strands of cloud sometimes appear in tufts of a distinctive form referred to by the common name of "mares' tails".

when do cirrus clouds usually appear in the sky They appear in advance of those storms' associated frontal systems, likely presaging a deterioration in weather conditions
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Cirrus cloud [SEP] Introduction
They also form from the outflow of tropical cyclones, and from the anvils of cumulonimbus clouds. They also arrive in advance of those storms' associated frontal systems, likely presaging a deterioration in weather conditions. Though indicating the arrival of precipitation, these clouds produce, themselves, at most fall streaks, whose ice crystals evaporate in warmer and drier air, without reaching ground level. Jet stream-powered cirrus can grow long enough to stretch across continents, while remaining only a few kilometers deep. Interaction of visible light with the ice crystals in them produces, below, optical phenomena such as sun dogs and halos. Cirrus is known to raise the temperature (due the heat released as water vapor freezes) of the air beneath the main cloud layer, by an average of 10 °C (18 °F), When the individual filaments become so extensive as to be virtually indistinguishable, one from another, they form a sheet of high cloud called cirrostratus.