US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
305 PM EST Tue Jan 29 2019
 
Valid Friday February 01 2019 - Tuesday February 05 2019
 
Hazards:

Heavy rain/mountain snow possible over the far northern Cascades for Fri-Sat, Feb 1-Feb 2.
Heavy rain possible across the western half of California into southwestern Oregon for Sat-Sun, Feb 
2-Feb 3.
Heavy snow possible along the Sierra Nevada for Sat-Sun, Feb 2-Feb 3.
Heavy wintry precipitation possible from the upper Midwest into the central Great Lakes for 
Sun-Mon, Feb 3-Feb 4.
Heavy precipitation possible over parts of the southern Great Basin for Sun, Feb 3.
Flooding occurring or imminent across portions of the Southeast, and to the south of Chicago, 
Illinois.
Much below normal temperatures from the upper Midwest to much of the Great Lakes on Friday, Feb 1.
Much below normal temperatures for the eastern portion of interior Alaska for Fri-Mon, Feb 1-Feb 4.
High significant wave heights for coastal portions of the Aleutians for Thu-Fri, Jan 31-Feb 1.
High winds possible over western Aleutians for Fri, Feb 1.

 
Detailed Summary:

The intense arctic outbreak will moderate and slide off the northeastern U.S. during the weekend.  
Much below normal temperatures will last one more day on Friday before milder air from the 
mid-section of the country arrives by the weekend.  The mild air mass will become firmly 
established across the central and southern Plains on Sunday, spreading into the Ohio Valley on 
Monday, and into much of the eastern and southeastern U.S. by Tuesday.   Temperatures are forecasts 
to be 20 to 30 degrees above normal across the mid-section of the country Sunday and Monday.  The 
next surge of arctic air from Canada is forecast to move into the northern Plains early next week.  
It appears that this arctic outbreak will be much less intense than the current one impacting the 
Northern Tier.

Out west, moisture ahead of a Pacific cyclone and associated fronts is expected to reach the 
Pacific Northwest on Friday.  The core of the storm should impact much of California on Saturday 
into Sunday where heavy rain is possible over the lower elevations while heavy snow is expected 
along the Sierras.  Some of the heavy rain could spill into parts of the southern Great Basin on 
Sunday as well.

The associated upper-level trough is forecast to move into the central Plains on Monday and into 
the Great Lakes on Tuesday.  Models are showing discrepancies on the speed and location of 
cyclogenesis of this system.  Nevertheless, wintry precipitation appears likely from the upper 
Midwest into the Great Lakes on Monday, reaching New England on Tuesday.  Potential exists for the 
wintry precipitation to become heavy across the upper Midwest into the Great Lakes on Monday.  By 
Tuesday, potential exists for another cyclone to intensify over the central Plains, bringing heavy 
rain across the mid-Mississippi Valley into the night-time hours.

In Alaska, much colder than normal temperatures are expected across interior eastern Alaska.  A 
strong Pacific cyclone is expected to spread significant waves and some high winds across western 
Aleutians Friday and Saturday.

Kong