US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
247 PM EDT Tue Mar 17 2020
 
Valid Friday March 20 2020 - Tuesday March 24 2020
 
Hazards:
- Heavy rain across portions of the Southeast, the Southern Appalachians, the Lower Mississippi 
Valley, the Southern Plains, and the Tennessee Valley, Fri, Mar 20 and Sun, Mar22.
- Heavy snow across portions of the Central Great Basin, California, and the Southwest, Sun-Tue, 
Mar 22-Mar 24.
- Flooding possible across portions of the Central Plains, the Northern Plains, the Southern 
Plains, the Middle Mississippi Valley, the Great Lakes, and the Ohio Valley.
- Flooding occurring or imminent across portions of the Southeast, the Lower Mississippi Valley, 
and the Northern Plains.
- Flooding likely across portions of the Northern Plains.
- High winds across portions of the Northeast, the Central Appalachians, the Mid-Atlantic, the 
Southern Appalachians, the Great Lakes, and the Ohio Valley, Fri-Sat, Mar 20-Mar 21.
- Much below normal temperatures across portions of the Central Plains, the Upper Mississippi 
Valley, the Southern Plains, the Northern Plains, and the Northern Rockies, Fri-Sat, Mar 20-Mar 21.
- Heavy snow across portions of mainland Alaska, Fri-Sat, Mar 20-Mar 21.
- High winds across portions of mainland Alaska, Fri, Mar 20.
- Much above normal temperatures across portions of mainland Alaska, Fri-Tue, Mar 20-Mar 24.
 
Detailed Summary:

The medium-range period (Friday 3/20 to Tuesday 3/24) will begin with a departing low pressure 
system across the Great Lakes/Northeast. This system will bring gusty winds to this region on 
Friday and Saturday, particularly across the Great Lakes and higher elevations of the Appalachians. 
Behind this system, well below average temperatures will be found across the Great Plains and Upper 
Midwest. Temperatures are forecast to dip into the single digits and below zero across certain 
portions of the Northern Plains. An associated cold front is forecast to stall once it reaches the 
Gulf of Mexico Friday night. This will produce heavy rain across the Deep South between Friday and 
the weekend. Total rainfall amounts could add up to near 3 inches in certain areas, leading to 
isolated flooding concerns.

Across the western U.S., a persistent upper-level trough and multiple oscillating upper-level lows 
will lead to cooler than average temperatures and chances for precipitation. The most impactful 
weather will be found across the Sierra Nevada, where another round of heavy snow (measured in 
feet) is increasingly likely between Sunday and Tuesday.

Active weather will be found across Northern and Western Alaska at the start of the medium range 
period. A strong low pressure system is forecast to bring gusty winds and heavy snow, possibly 
leading to blizzard conditions along the West Coast on Friday. Temperatures are forecast to run 20 
to 40 degrees above average across northern Alaska, which could mean the first time at or above 
freezing since Autumn for some portions of the state. 

Snell