US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
350 PM EST Tue Nov 17 2020
 
Valid Friday November 20 2020 - Tuesday November 24 2020
 
Hazards:
- Heavy rain across portions of the Pacific Northwest and the Northern Great Basin, Sun-Tue, Nov 
22-Nov 24.
- Heavy rain across portions of the Central/Southern Plains, and the Mississippi Valley, Sat-Sun, 
Nov 21-Nov 22.
- Heavy snow across portions of the Pacific Northwest, the Northern Rockies, and the Northern Great 
Basin, Fri, Nov 20.
- Flooding occurring or imminent across portions of the Southeast and the Mid-Atlantic.
- Heavy precipitation across portions of mainland Alaska, Sat, Nov 21.
- High winds across portions of mainland Alaska and the Aleutians, Fri-Sat, Nov 20-Nov 21.
 
Detailed Summary:

A series of upper-level disturbances will be the impetus for hazardous weather over the CONUS 
during the medium range period (Friday, November 20th - Tuesday, November 24). The first 
disturbance will arrive at the beginning of the weekend, this Friday. This disturbance will produce 
heavy snow for the Northern Cascades and Northern Rockies on Friday. As this shortwave propagates 
east, it will organize an area of surface low pressure along the lee of the Rockies which will go 
on to be the focus for heavy rain over the Mid-South on Saturday and Sunday. Light snowfall may mix 
in some places within the cold sector of this system. Temperatures are likely to remain above 
average for much of the eastern U.S. throughout the medium range. 

Another disturbance is forecast to impacting the Pacific Northwest on Sunday. This system may 
produce some heavy rain for the region before a stronger closed upper-level low arrives behind it 
on Monday. This potent system is forecast to produce heavier rainfall from the Panhandle of Alaska 
down to the Pacific Northwest on Monday and Tuesday. Heavy snow is also likely during this period 
for the Pacific Northwest mountains.

In Alaska, an upper-level low will spin up over the Aleutians on Friday. This will produce high 
winds for the islands and mainland through Saturday. Heavy precipitation will join in over the 
southwestern mainland on Saturday as the surface low moves toward the Gulf of Alaska. This area of 
low pressure may produce heavy precipitation and high winds for the Panhandle of Alaska heading 
into midweek. 

Kebede