US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
504 PM EDT Wed Mar 11 2020
 
Valid Saturday March 14 2020 - Wednesday March 18 2020
 
Hazards:
- Heavy snow for the southern Cascades, Sat, Mar 14.
- Heavy snow across portions of the northern Plains, Sat-Sun, Mar 14-Mar 15.
- Heavy snow from across the higher elevations of northern California down along the Sierra Nevada, 
and across northwestern Wyoming, Sat-Mon, Mar 14-Mar 16.
- Heavy precipitation for portions of the higher elevations from central Nevada to southern Idaho, 
Sat-Sun, Mar 14-Mar 15.
- Heavy precipitation for portions of the higher elevations of southern California, Arizona, Utah, 
and Colorado, Mon-Wed, Mar 16-Mar 18.
- Heavy rain from the southern Plains eastward into the southern Appalachians as well as parts of 
central California, Sat-Sun, Mar 14-Mar 15.
- Heavy rain across portions of extreme southern California, Mon-Tue, Mar 16-Mar 17.
- Heavy rain from the central and southern Plains eastward into the Ohio Valley, Mon-Wed, Mar 
16-Mar 18.
- Much below normal temperatures from interior Pacific Northwest eastward across the northern 
Rockies into the northern Plains, Sat-Wed, Mar 14-Mar 18.
- Flooding possible across portions of the Southeast.
- Flooding occurring or imminent across portions of the Southeast, the Lower Mississippi Valley, 
the Upper Mississippi Valley, and the Northern Plains.
- Flooding likely across portions of the Southeast, the Upper Mississippi Valley, and the Northern 
Plains.
- Heavy snow across portions of western Alaska, Sun, Mar 15, and Wed, Mar 18.
- Much below normal temperatures across portions of southern Alaska, Sat, Mar 14.
- Much above normal temperatures across much of western and northern Alaska, Sat-Wed, Mar 14-Mar 18.


Detailed Summary:

The weather pattern across the continental U.S. will be highlighted by a pair of upper-level 
troughs digging into the Southwest in contrast with an upper-level ridge over the Gulf of Mexico.  
Southwesterly flow between these two atmospheric features will tap into a rich source of 
subtropical moisture and result in areas of heavy rain from the Southwest and the southern Plains 
to the lower Mississippi Valley and Mid-South.  By Saturday, areas of heavy rain are expected to 
develop over the central Plains and then expand eastward into the southern Appalachians ahead of a 
low pressure center that is forecast to form along a stationary front.   This front will remain the 
focus for more heavy rain to develop over the central to southern Plains for the first half of next 
week ahead of the next significant upper-level trough approaching from the western U.S.

Further north, a dome of cold Canadian high pressure will result in plunging temperatures from 
across the northern Rockies into the Northern Plains early next week. Temperatures as much as 40 
degrees below normal are possible with the coldest temperatures centered in northwest Montana. This 
cold regime will set the stage for heavy mountain snow from the interior Northwest to the northern 
and central Rockies this weekend and into next Monday.  It appears that the Sierra Nevada will pick 
up heavy snow starting Saturday night, lasting into the first half of next week.

Over Alaska, the recent cold regime is forecast to reach its final day on Saturday as the cold 
upper trough gives way to a rapidly building warm ridge of high pressure ahead of a strong low 
pressure system across northeastern Siberia, leading to a significant warm-up in temperatures. The 
axis of this upper ridge is forecast to remain nearly stationary over the Gulf of Alaska and 
south-central Alaska with much above normal temperatures continuing into the middle of next week.  
To the northwest, expect gusty winds and a threat for heavy snow to develop across portions of 
western Alaska ahead of the low pressure wave on Sunday.  The chance of heavy snow is forecast to 
increase once again by next Wednesday as a large-scale cyclone is forecast to edge closer toward 
western Alaska.

Kong