US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
228 PM EST Fri Mar 05 2021
 
Valid Monday March 08 2021 - Friday March 12 2021
 
Hazards:
- Heavy rain across portions of the Central Plains, the Lower Mississippi Valley, the Southern 
Plains, the Middle Mississippi Valley, the Great Lakes, and the Ohio Valley, Fri, Mar 12.
- Heavy rain across portions of the Central Plains, the Middle Mississippi Valley, the Great Lakes, 
the Ohio Valley, and the Upper Mississippi Valley, Wed-Thu, Mar 10-Mar 11.
- Heavy snow across portions of California, the Central Great Basin, the Pacific Northwest, and the 
Southwest, Tue-Wed, Mar 9-Mar 10.
- Flooding occurring or imminent across portions of the Southeast, the Lower Mississippi Valley, 
and the Ohio Valley.
- Flooding likely across portions of the Ohio Valley.
- Heavy precipitation across portions of mainland Alaska, Mon, Mar 8.
- Heavy snow across portions of mainland Alaska, Mon, Mar 8.
- High winds across portions of mainland Alaska, Mon-Tue, Mar 8-Mar 9.
- High winds across portions of the Aleutians, Thu-Fri, Mar 11-Mar 12.
 
Detailed Summary:

The focus for hazardous weather during the medium range period (Monday, March 8th - Friday, March 
12th) will likely be in the central U.S. and parts of western/southern Alaska. An upper-level low 
will begin swooping into the western U.S. on Monday. Heavy snow ranging between 8-12 inches is 
expected for much of the Sierra between Monday and Tuesday as the associated surface low pressure 
system drops into the Southwest. A proceeding frontal system will produce snowfall across the 
Northern Rockies on Monday and Tuesday, but not enough to warrant a hazard area. Warm air will 
continue to flow into the north-central U.S. ahead of this system which will potentially lead to 
widespread high and low temperature records being broken from the Northern/Central Plains to the 
Upper Midwest between Monday and Tuesday night. This warm air mass will move into, and settle over, 
the eastern third of the country later next week. Colder air will move into the Western U.S. during 
this mid-late week period.

The same system that will produce snowfall over the Northern Rockies and pull warm air into the 
eastern half of the country will also generate heavy rain across parts of the Midwest and 
Mississippi Valley mid-week. Heavy rain is possible for a swath extending from northern Missouri 
into northwest Indiana and southern Wisconsin between Wednesday and Thursday. The heavy rain threat 
may shift south, into the eastern Oklahoma, northwestern Arkansas, southern/central Missouri, 
southern/central Illinois and western Indiana on Friday as the slow moving cold front propagates 
southward. Confidence is still relatively low on this hazard area so it is subject to change.

In Alaska, a series of systems will produce high winds and heavy precipitation for much of Alaska's 
western and southern regions. A potent low pressure system will produce heavy snow across much of 
the northwest coast on Monday. This system may also generate high winds across much of Alaska's 
west coast between Monday and Tuesday. Heavy precipitation is also possible across the southern 
portion of the Mainland coast on Monday due to this system. A new system will arrive in the far 
western Aleutians on Friday, bringing with it the threat for heavy winds to the western Aleutians. 
Heavy precipitation may impact the southeast Alaskan coast between Thursday and Friday as a system 
moves into the Gulf.

Kebede