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Significant Coastal Impacts to the Eastern Seaboard; Tropical Storm Nolo to Impact Hawaii

A Nor'easter will bring significant coastal impacts to the Mid-Atlantic and New England through the weekend. Moderate to major coastal flooding, heavy rain, strong winds and high surf expected. Tropical Storm Nolo will continue to strengthen as it moves north toward the Big Island of Hawaii. Heavy rainfall may bring life-threatening, catastrophic flooding and mudslides through the weekend. Read More >

 

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.

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