Supercooled Warm-Rain Processes
the formation of freezing rain
A less common way that
freezing rain forms is through
supercooled warm-rain process (SWRP), where cloud top
temperatures are warmer than about -10C.
Supercooled raindrops develop as microscopic cloud droplets
collect one another as they fall.
Ice processes are not involved in the formation of these
The precipitation falls to the surface as supercooled rain or
drizzle and freezes instantly on contact.
The raindrops do not freeze within the cold layer because there are very few
in the presence of warmer temperatures.
The freezing rain forms a coat of ice on everything.
This picture shows several tree branches coated with a
thick layer of ice that accumulated during a
central Illinois ice storm.|