US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
400 PM EST Fri Nov 20 2020
 
Valid Monday November 23 2020 - Friday November 27 2020
 
Hazards:
- Heavy rain across portions of the Lower/Middle Mississippi Valley, the Tennessee/Ohio Valley, the 
Southern Appalachians, and the Southeast, Wed, Nov 25.
- Heavy rain across portions of the Middle/Upper Mississippi Valley, and the Great Lakes, Tue, Nov 
24.
- Heavy snow across portions of the Pacific Northwest and the Northern Great Basin, Tue, Nov 24.
- Flooding occurring or imminent across portions of the Southeast and the Mid-Atlantic.
- High significant wave heights for coastal portions of the Pacific Northwest, Wed, Nov 25.
- Heavy precipitation across portions of mainland Alaska, Wed, Nov 25.
- Heavy precipitation across portions of the Alaska Panhandle, Mon, Nov 23 and Thu, Nov 26.
- High winds across portions of the Alaska Panhandle and mainland Alaska, Mon-Tue, Nov 23-Nov 24.
- High significant wave heights for coastal portions of the Alaska Panhandle and mainland Alaska, 
Mon, Nov 23.
- High significant wave heights for coastal portions of the Alaska Panhandle, Tue, Nov 24.
 
Detailed Summary:

Hazardous weather will impact parts of the Northwest, the eastern half of the CONUS and coastal 
Alaska during the medium range period next week (Monday, November 23rd - Friday, November 27th). A 
low exiting the Northeast may produce some lingering lake effect snow over upstate New York on 
Monday. A pair of low pressure systems emerging over the Central/Southern Plains will pull 
substantial moisture northward on Tuesday. This will lead to a chance for heavy rain over the 
Middle/Upper Mississippi Valley that day. As the low pressure waves consolidate they will threaten 
the Tennessee/Middle Mississippi Valleys and greater Southeast with heavy rain on Wednesday. 

In the Northwest, a cold front will produce heavy snow over the Northern Cascades and rainfall over 
the lower elevations on Tuesday. A potent area of low pressure will follow on Wednesday. This 
system will be strong enough to generate significant waves along the Pacific Northwest coast 
extending from Washington state down through Oregon.

Meanwhile in Alaska, the aforementioned low pressure system over the Gulf will produce significant 
waves and high winds for the southern mainland coast as well as heavy precipitation over the 
southern panhandle on Monday. This system will arrive along the Panhandle on Tuesday. It will 
continue to generate enough winds that the significant wave threat will move from the mainland 
coast into the panhandle. The emergence of a new area of low pressure over the Bering Sea will send 
a frontal system across the Aleutians and southern mainland on Wednesday. A new surface low will 
develop along this boundary and generate heavy precipitation over the central/southern mainland 
coast on Wednesday. As this system propagates east it will produce heavy precipitation over the 
southern panhandle on Thanksgiving day. The area of low pressure over the Bering Sea may be the 
focus for high winds and heavy precipitation on Friday, but there isn't enough model confidence to 
issue any hazards for that area at this time.

Kebede