Freezing Rain
On Feb 9, 8:58*am, Desperate Dan wrote:
On Feb 8, 8:01*pm, "Eskimo Will" wrote:
"Alan" wrote in message
....
On Feb 8, 7:25 pm, "Col" wrote:
The local forecast wastalking at length about freezing rain thisevening, and how unusual it is, so I amassuming 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 160masl
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. Ifthisabove
zero layer of air is deep enough it will turn the snow completely into rain. Ifthisrain then hits anotherlayer 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. *Ifthis
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.
===============================================
Just to add to that excellent explanation that proper freezing rain is when
supercooled rain drops hit a cold surface and freeze instantly on impact.
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