Alan wrote:
On Feb 8, 7:25 pm, "Col" wrote:
The local forecast was talking at length about freezing rain
this evening, and how unusual it is, so I am assuming that it
is to be of the genuine 'supercooled' varity, rather than
just 'normal' rain making cold surfaces slippery.

So what makes freezing rain fall at temperatures when
one would normaly expect snow?
--
Col

Bolton, Lancashire
160m asl

Snow will fall if the whole layer of air is sub-zero. But if the snow
hits a layer of air above zero it will start to melt. If this above
zero layer of air is deep enough it will turn the snow completely into
rain. If this rain then hits another layer of sub-zero air, for
instance a surface inversion, it will be cooled. If the surface
inversion is too shallow the rain won’t have a chance to drop below
zero, thus your 'normal' rain making cold surfaces slippery. If this
sub-zero layer is deep enough the rain’s temperature will have a
chance to drop below zero. Sometimes it will refreeze and give ice
pellets; sometime you will get proper super-cooled rain.

Thanks for the explanation.
That ties in with what I observed for a period of time on Saturday
afternoon, a mixture of ice pellets and what I suspected to be
freezing rain, what with the temp at -2C.
--
Col

Bolton, Lancashire
160m asl