US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
458 PM EDT Mon Mar 16 2020
 
Valid Thursday March 19 2020 - Monday March 23 2020
 
Hazards:
- Heavy precipitation across portions of the southwest Colorado into northern New Mexico, Thu, Mar 
19 and Sat, Mar 21.
- Heavy precipitation from portions of the central Rockies across the High Plains into the Northern 
Plains, Thu, Mar 19.
- Heavy rain from central Texas through portions of the lower to mid-Mississippi Valley, the 
Tennessee Valley, and into the Ohio Valley, as well as portions of the interior Northeast, Thu-Fri, 
Mar 19-Mar 20.
- Heavy rain from portions of eastern Texas into the lower Mississippi Valley, Sat-Sun, Mar 21-Mar 
22.
- Heavy snow along the Sierra Nevada, Sun-Mon, Mar 22-Mar 23.
- Flooding possible across portions of the Dakotas, the middle Mississippi Valley, and Oklahoma.
- Flooding occurring or imminent across portions of the Southeast, the lower Mississippi Valley, 
and eastern South Dakota.
- Flooding likely across portions of the northern Plains.
- High winds from across portions of the the central Rockies, through much of the central to 
northern Plains, into the upper Midwest and upper Great Lakes, Thu, Mar 19.
- High winds from across the Great Lakes and northern Ohio Valley through the Northeast, Fri-Sat, 
Mar 20-Mar 21.
- Much below normal temperatures across much of the northern and central High Plains, through the 
northern Plains into the upper Midwest, Thu-Fri, Mar 19-Mar 20.
- Heavy snow across portions of western Alaska, Thu-Fri, Mar 19-Mar 20 and Sun, Mar 22.
- Heavy snow across portions of southwestern mainland Alaska, Fri-Sat, Mar 20-Mar 21.
- High winds across portions of mainland Alaska, Thu-Fri, Mar 19-Mar 20 and Sun, Mar 22.
- Much above normal temperatures across much of northwestern to northern Alaska, Thu-Mon, Mar 
19-Mar 23.
 
Detailed Summary:

The medium-range period will begin with an intensifying low pressure system moving rapidly 
east-northeast through the central Plains.  At the same time, arctic air behind a cold front will 
be ushered down through the northern Plains behind the intensifying storm.  This combination will 
likely bring a swath of heavy precipitation from the central Rockies across the High Plains into 
the northern Plains on Thursday.  It appears that precipitation will begin as rain over the central 
High Plains early on Thursday.  But as the low pressure system intensifies rapidly during the day, 
the rain will likely change over to heavy snow rapidly from west to east together with plummeting 
temperatures as winds increase to gale force with violent gusts possible behind the arctic front!  
The heavy snow could rapidly spread farther east into the upper Midwest Thursday evening.  Due to 
the swift motion of the intensifying storm, the heavy snow could end quickly overnight along with 
plummeting temperatures for the upper Midwest and into the central Great Lakes.  An arctic high 
pressure system will then push much colder than normal temperature down the High Plains and 
eastward into the upper Midwest on Thursday and into Friday.

To the south and east of the intensifying storm, rain and thunderstorms will become widespread.  In 
fact, heavy rain can be expected to impact areas from central Texas through portions of the lower 
to mid-Mississippi Valley, the Tennessee Valley, and into the Ohio Valley as well as portions of 
the interior Northeast Thursday into Friday.  The trailing portion of the cold front is forecast to 
become stationary off the Gulf Coast during the weekend.  This will keep a good chance of rain for 
the Gulf States, especially from eastern Texas to the lower Mississippi Valley, where rain could be 
heavy during the weekend.

Meanwhile, the upper-level pattern over the eastern Pacific continues to favor the development of 
cut-off lows.  Although forecast uncertainty is quite high in this area, it appears that moisture 
ahead of one of such cut-off lows will bring meaningful precipitation along the West Coast during 
the weekend.  The precipitation should be in form of snow over the higher elevations of the Sierra 
Nevada through the weekend, and it is expected to be heavy.  Some of the precipitation could spill 
into the interior western U.S. on Sunday and into Monday.

In Alaska, the recent switch in the synoptic pattern will continue to bring about an active storm 
track through northeastern Siberia into the Arctic Ocean.  This highly anomalous pattern will 
sustain the much milder than normal temperatures across northwestern to northern Alaska through 
much of the medium-range period.  Together with the anomalous warmth will be the arrival of snow as 
a couple of strong low pressure systems are forecast to pass to the west and northwest of Alaska. 
One such system will likely spread gusty gale-force winds together with heavy snow into portions of 
western Alaska where blizzard conditions are possible on Thursday and Friday. The area may catch a 
break on Saturday before the next low pressure system could bring more snowy and windy conditions 
into western Alaska on Sunday, and then possibly northern Alaska next Monday.

Kong