On Apr 16, 3:12 pm, "Stuart" wrote:
What causes haze, and how is it predicted?

Any solid particles in suspension. This in effect means
either dust or smoke. Water vapour cannot cause haze because it is
invisible.
Sometimes when the sun is seen through a thin high layer of
cloud this is referred to as hazy sunshine but this is incorrect. The
terms "watwery" or "milky" would be better. Met Office presenters
don't know what haze is, or at least are told not to know, just like
footballers with brains find life easier if they pretend they haven't
got them.

Tudor Hughes.