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Moke Impacts Hawaii; Severe Thunderstorms and Heavy Rainfall from the Great Basin to the Plains

Heavy rain and gusty winds from Tropical Storm Moke will impact the Big Island into Monday, risking life-threatening flooding and mudslides in windward and southeast areas. Severe thunderstorms are expected across the northern Rockies/Plains and northern Great Basin. Dangerous heat persists across the Southern Plains and Lower Mississippi Valley, building further into the Southwest by midweek. 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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