US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
252 PM EST Fri Feb 14 2020
 
Valid Monday February 17 2020 - Friday February 21 2020
 
Hazards:
- Heavy precipitation across portions of the Southern Rockies and the Southern Plains, Wed-Thu, Feb 
19-Feb 20.
- Heavy rain across portions of the Southern Plains, Wed-Thu, Feb 19-Feb 20.
- Heavy rain across portions of the Southeast, the Mid-Atlantic, the Lower Mississippi Valley, the 
Southern Appalachians, and the Tennessee Valley, Mon-Tue, Feb 17-Feb 18.
- Heavy snow across portions of the Great Lakes, and the Upper Mississippi Valley, Mon, Feb 17 and 
portions of the Northeast and the Great Lakes, Tue, Feb 18.
- Heavy snow across portions of the Central and Southern Rockies, Mon-Tues, Feb 17-18.
- Flooding possible across portions of the Southeast, the Lower Mississippi Valley, and the 
Southern Plains.
- Flooding occurring or imminent across portions of the Lower Mississippi Valley, the Tennessee 
Valley, the Middle Mississippi Valley, the Mid-Atlantic, the Southeast, the Pacific Northwest, and 
the Ohio Valley.
- Flooding likely across portions of the Southeast, the Ohio Valley, and the Tennessee Valley.
- Much below normal temperatures across portions of the Central Plains, the Central Rockies, the 
Central Great Basin, the Northern Plains, the Northern Rockies, the Southern Rockies, the Southern 
Plains, and the Southwest, Tue-Thu, Feb 18-Feb 20.
- Much below normal temperatures across portions of the Middle Mississippi Valley, the Great Lakes, 
the Upper Mississippi Valley, and the Northern Plains, Tue-Wed, Feb 18-Feb 19.
- Heavy precipitation across portions of the Alaska Panhandle and southern mainland Alaska, 
Tue-Fri, Feb 18-Feb 21.
- Heavy snow across portions of southern mainland Alaska, Mon-Thu, Feb 17-Feb 20.
- Much below normal temperatures across portions of mainland Alaska, Mon, Feb 17 and Thu-Fri, Feb 
20-Feb 21.
 
Detailed Summary:

A developing storm system in the Nation's Heartland will lead to a pair of notable hazards in the 
eastern half of the U.S. starting late Sunday night and into Monday in the Midwest. The first 
hazard to discuss is the potential for heavy snow in parts of the Great Lakes on Monday. As the 
storm tracks north and east, the potential for heavy snow will shift to northern New England on 
Tuesday. There is the potential for an icy wintry mix to cause some slick spots in the interior 
Northeast Tuesday morning, but a changeover to rain is expected later in the day. Farther south, 
heavy rain is possible in portions of the Southeast and southern Appalachians late Monday and into 
Tuesday. The region's overly saturated soil and swollen rivers will make the area susceptible to 
additional flash flooding. 

Behind this storm system, a dome of Arctic high pressure will usher in bitterly cold temperatures 
and frigid wind chills across the Rockies and portions of the Upper Midwest starting Monday and 
persisting into the second half of the week. Easterly low-level winds will lead to heavy mountain 
snow in parts of the southern and Central Rockies. Temperature anomalies will average 12 to 20 
degrees below normal across much of these regions with the coldest anomalies possibly located in 
West Texas next Wednesday and Thursday. An upper-level trough in the southwestern U.S. will produce 
areas of precipitation across the lower Four Corners states and West Texas which may fall in the 
form of heavy snow or an icy wintry mix on both Wednesday and Thursday.

Across Alaska much below normal temperatures will stick around in parts of central and northern 
Alaska for one more day on President's Day. Temperatures will temporarily moderate over the 
east-central and northeastern parts of the mainland mid-week as a strong Pacific storm moves into 
the Gulf of Alaska and possibly inland over southeastern Alaska and draws milder air northward. 
This storm is also responsible for potentially heavy snow across the south-central/southeastern 
mainland (especially the Copper River Basin area) Monday and into Tuesday then into the Panhandle 
mid-week (where both rain and snow are expected). A second storm system may follow on the first 
storm's coat-tails with potentially more wintry weather in the southern mainland and additional 
heavy rain and snow over the Panhandle late week. Arctic air building in behind these systems will 
lead to plummeting temperatures with the core of the coldest air expected over western Alaska and 
the eastern Aleutians.

Mullinax