US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
309 PM EST Thu Jan 16 2020
 
Valid Sunday January 19 2020 - Thursday January 23 2020
 
Hazards:
- Heavy precipitation across portions of California and the Pacific Northwest, Tue-Wed, Jan 21-Jan 
22.
- Heavy precipitation across portions of the Central Plains, the Middle Mississippi Valley, and the 
Southern Plains, Thu, Jan 23.
- Heavy rain across portions of the Middle Mississippi Valley, the Lower Mississippi Valley, and 
the Southern Plains, Thu, Jan 23.
- Heavy snow across portions of the Central Great Basin, California, and the Southwest, Tue-Wed, 
Jan 21-Jan 22.
- Heavy snow across portions of the Northeast and the Great Lakes, Sun, Jan 19.
- Flooding possible across portions of the Central Plains, the Tennessee Valley, the Great Lakes, 
the Middle Mississippi Valley, the Upper Mississippi Valley, the Southeast, the Southern Plains, 
and the Ohio Valley.
- Flooding occurring or imminent across portions of the Lower Mississippi Valley, the Northern 
Plains, the Tennessee Valley, the Middle Mississippi Valley, the Southeast, the Great Lakes, and 
the Ohio Valley.
- Flooding likely across portions of the Middle Mississippi Valley.
- Much below normal temperatures across portions of the Central Plains, the Middle Mississippi 
Valley, the Upper Mississippi Valley, and the Northern Plains, Sun-Tue, Jan 19-Jan 21.
- Much below normal temperatures across portions of the Northern Plains, Sun, Jan 19.
- Heavy precipitation across portions of the Alaska Panhandle, Sun-Tue, Jan 19-Jan 21.
- Much below normal temperatures across portions of mainland Alaska, Sun-Mon, Jan 19-Jan 20.
 
Detailed Summary:

The start of the forecast period includes portions of northern New England receiving heavy snow on 
the backside of the exiting weekend storm system. Meanwhile, as colder temperatures spill in from 
the northwest, bands of lake effect snow showers will form downwind of Lakes Erie and Ontario late 
Sunday and into Monday. Snowfall rates are expected to be heavy within these bands with localized 
totals exceeding 8" possible. In addition to the snow, winds will pick up behind the storm leading 
to areas blowing and drifting snow. Travel will likely be affected in areas that are impacted by 
lake effect snow bands.

In wake of this weekend's storm, a strong, cold high pressure system will dive southward from 
central Canada into the Northern Plains/Midwest early week. Bitterly cold temperatures will spread 
across these regions along with frigid wind chills. Portions of the Northern Plains and Midwest 
will see daily low temperatures plunge below zero both Sunday and Monday. Daily low temperature 
anomalies will average nearly 15 degrees below normal both days with high temperatures anomalies 
ranging between 20 to 25 degrees below normal. As high pressure drifts southeast, southerly flow 
will usher in milder temperatures by mid-week. Cold temperatures associated with this dome of high 
pressure will reach the East Coast the first half of the week but temperatures will not be quite as 
frigid as they were in the Northern Plains and Midwest.

While model guidance contains some differences on timing, they are coming into better agreement on 
an amplifying upper-level trough that will track into the western U.S. on Tuesday. Precipitation 
amounts could become heavy with an opportunity for very heavy mountain snow in Sierra Nevada. Model 
guidance begins to diverge more in forecast days 6-7, but ensemble guidance point to the potential 
for an intensifying storm system in the South Central U.S. next Wednesday and Thursday. Potential 
hazards include heavy rainfall in the Southern Plains and Lower Mississippi Valley, plus potential 
winter weather in the Central Plains.

Over Alaska, below normal temperatures are expected to continue for the lower elevations of the 
mainland into Monday. A storm system in the Gulf of Alaska is likely to affect the Panhandle and 
potentially along the Gulf of Alaska coast Sunday through Tuesday. Guidance has become wetter along 
the Panhandle during this period but the onset of the precipitation could end up falling later in 
the day on the Sunday.


Mullinax