US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
328 PM EST Mon Feb 25 2019
 
Valid Thursday February 28 2019 - Monday March 04 2019
 
Hazards:
Heavy precipitation across portions of California and the Southwest, Sat-Sun, Mar 2-Mar 3.
Heavy rain across portions of the Southeast and the Lower Mississippi Valley, Mon, Mar 4.
Heavy snow across portions of the Central Plains, the Central Rockies, the Central Great Basin, the 
Southern Plains, the Northern Great Basin, the Southern Rockies, California, the Pacific Northwest, 
and the Southwest, Sat-Mon, Mar 2-Mar 4.
Heavy snow across portions of the Central Plains, the Central Great Basin, the Northern Plains, the 
Northern Rockies, the Central Rockies, and the Northern Great Basin, Thu-Fri, Feb 28-Mar 1.
Heavy snow across portions of the Northeast and the Great Lakes, Sat-Sun, Mar 2-Mar 3.
Flooding possible across portions of the Tennessee Valley, the Middle Mississippi Valley, the 
Mid-Atlantic, the Southern Appalachians, the Southeast, and the Ohio Valley.
Flooding occurring or imminent across portions of the Lower Mississippi Valley, the Tennessee 
Valley, the Middle Mississippi Valley, the Mid-Atlantic, the Southern Appalachians, the Southeast, 
the Pacific Northwest, and the Ohio Valley.
Flooding likely across portions of the Tennessee Valley, the Middle Mississippi Valley, the 
Mid-Atlantic, the Southern Appalachians, the Southeast, and the Ohio Valley.
Much below normal temperatures across portions of the Central Plains, the Great Lakes, the Lower 
Mississippi Valley, the Central Appalachians, the Northern Plains, the Tennessee Valley, the 
Pacific Northwest, the Northern Rockies, the Central Rockies, the Middle Mississippi Valley, the 
Northeast, the Southern Appalachians, the Northern Great Basin, the Upper Mississippi Valley, the 
Mid-Atlantic, the Southern Plains, and the Ohio Valley, Thu-Mon, Feb 28-Mar 4.
High winds across portions of mainland Alaska, Thu, Feb 28.
High significant wave heights for coastal portions of mainland Alaska and the Aleutians, Thu, Feb 
28.
High significant wave heights for coastal portions of the Aleutians, Sat-Mon, Mar 2-Mar 4.
 
Detailed Summary:

The Western U.S. will continue to see active weather in the medium range. A wave of low pressure 
and associated arctic cold front will sweep through the Northern Rockies and Northern Great Basin 
Thursday into Friday (Feb 28-Mar 1), bringing heavy snow to the higher elevations. Another system 
will enter in its wake on Saturday and quickly spread snow across the Great Basin into the Central 
Rockies by Sunday. The snow should linger into Monday across northern New Mexico and Colorado. 
Widespread snow totals greater than 6 inches are expected from the Great Basin to the Central and 
Northern Rockies during this time frame, with well over a foot of snow in the Sierra Nevada. 
Meanwhile, the aforementioned system could bring heavy rain along the California coast, 
specifically central California, on Saturday and Sunday. Temperatures well below average will be 
likely in the northern Rockies and east of the Cascades. 

The main story across the central and eastern U.S. will be widespread temperatures well below 
average. Arctic high pressure located over the north-central U.S. will sink southward into the 
Southern Plains and Lower Mississippi Valley behind a cold front early on Saturday. The core of the 
cold air will remain over Northern and Central Plains, as well as the upper Midwest. Here, maximum 
temperature anomalies will be 20 to 30 degrees below normal from Thursday to Monday. This would 
equate to high temperatures around zero in the Northern Plains.

Uncertainty remains high with respect to precipitation in the Central and Eastern U.S. Waves of low 
pressure exiting the Rockies could bring light rain and snow through Saturday from the Plains to 
Northeast. One of these waves could further develop near the Lower Great Lakes on Saturday. The 
area with the greatest chance of heavy snow remains northern New England as low pressure could 
develop off the coast Sunday. Further south, heavy rain along a stalled frontal boundary will be 
possible from the central Gulf Coast to the Southeast.  

For western Alaska and the Aleutians, high winds and significant waves (greater than 20 feet) will 
be likely thanks to a strong low pressure system passing to the west of Alaska in the Bering Sea on 
Thursday. Another larger system is forecast to pass further west and bring significant wave heights 
to the Aleutians from Saturday to Monday (Mar 2- Mar 4).


Snell