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Freezing Drizzle Explained

There is a very small margin of error in determining primarily light snow vs. light freezing drizzle for forecasters.  However, the difference in impacts between these two precipitation types is often significant, with freezing drizzle prone to quickly cause slick surfaces, even with only trace amounts.



Model Analysis
An 8 am model analysis sounding near Romeoville, IL, indicating a saturated layer that was within temperatures close to both flurries/snow grains and supercooled liquid for freezing drizzle. 

Radar Loop
Radar loop and observations during from 9 pm January 23 through 12 pm January 24.  A gradual expansion in light echoes occurs during the overnight/early morning of the 24th.  There are some embedded heavier echoes that are likely light freezing rain showers.  As an indication of that, NWS Chicago recorded 0.05" of liquid during the morning of January 24.


NWS Chicago Science & Past Events Page

2017-2018 Winter Events