US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
338 PM EST Thu Jan 07 2021
 
Valid Sunday January 10 2021 - Thursday January 14 2021
 
Hazards:
- Heavy precipitation across portions of the Pacific Northwest and the Northern Great Basin, 
Mon-Tue, Jan 11-Jan 12.
- Heavy rain across portions of the Southern Plains, Sun, Jan 10.
- Heavy snow across portions of the Southern Plains, Sun, Jan 10.
- Flooding occurring or imminent across portions of the Southeast, the Southern Plains, the 
Mid-Atlantic, and the Pacific Northwest.
- Flooding likely across portions of the Mid-Atlantic.
- High winds across portions of the Central Rockies, and the Northern/Central Plains, Thu, Jan 14.
- Heavy precipitation across portions of the Alaska Panhandle and mainland Alaska, Sun-Mon, Jan 
10-Jan 11.
- High winds across portions of mainland Alaska, Sun-Mon, Jan 10-Jan 11.
 
Detailed Summary:

Low pressure over Northeastern Mexico on Sunday will aid in produce snow over parts of the 
Central/Southern Rockies and Central/Southern High Plains will spread into parts of the Southern 
Plains on Sunday.  The snow will be heavy enough to meet warning criteria for an area of heavy 
snow.  Furthermore, an area of heavy rain will develop along the Western Gulf Coast on Sunday.

As the system moves across the Northern Gulf of Mexico, rain and snow will develop over parts of 
the Lower Mississippi Valley.  The rain and snow but will not meet the criteria for depicting on 
the Hazards Map on Monday.  The rain and snow will be along the northern edge of the precipitation 
shield. Wet snow will develop over parts of the Tennessee Valley into parts of the Southern 
Appalachians. By Tuesday, the system will move to the Southeast. As the system moves off the coast, 
there is some uncertainty of the exact track.  If the system moves closer to the coast, the greater 
the likelihood of snow developing across the Central Appalachians into the Northeast is. If the 
storm moves farther east, the snow is less likely.   At this point, some wet snow will develop 
across the Northern Mid-Atlantic into parts of the Northeast, but with not a lot of cold air in 
place, the snow amounts will be less than the criteria for depicting snow on the Hazards Map. 

Meanwhile, a front will approach the Northwest, producing rain and higher elevation snow across 
parts of the Pacific Northwest on Monday and Tuesday.  An area of heavy precipitation is depicted 
on the chart with this system.  The low associated with the system will move into Western Canada, 
moving eastward to Central Canada by Thursday.  The pressure gradient over the Central 
Rockies/Central High Plains and of the Northern Plains will be strong enough to produce high wind 
over parts of the region; therefore, an area of high winds is on the map.

Over Alaska, an area of deep low pressure will be over the Gulf of Alaska on Sunday.  The storm 
will have a plume of moisture that will move into the South-Central portions of the mainland and 
parts of the Alaska Panhandle, producing an area of heavy precipitation from Kendal Peninsula 
eastward to Alaska's Panhandle on Sunday and Monday.  The pressure gradient associated with the 
deep low will make wind strong enough to meet the high winds criteria on mainly Sunday, weakening 
on Monday from Kodiak Island eastward to parts of the Kenai Peninsula.

Ziegenfelder