US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
351 PM EDT Tue Mar 19 2019
 
Valid Friday March 22 2019 - Tuesday March 26 2019
 
Hazards:
- Heavy rain across portions of California and the Pacific Northwest, Tue, Mar 26.
- Flooding possible across portions of the Northern/Central Plains, the Tennessee Valley, the 
Upper/Middle Mississippi Valley, and the Great Lakes.
- Flooding occurring or imminent across portions of the Northern/Central Plains, Mississippi 
Valley, the Tennessee Valley, the Great Lakes, and the Ohio Valley.
- Flooding likely across portions of the Northern/Central Plains, the Upper/Middle Mississippi 
Valley, and the Great Lakes.
- Heavy precipitation across portions of the Alaska Panhandle and mainland Alaska, Fri-Mon, Mar 
22-Mar 25.
- Heavy precipitation across portions of mainland Alaska and the Aleutians, Mon-Tue, Mar 25-Mar 26.
- High winds across portions of mainland Alaska and the Aleutians, Fri, Mar 22.
- High winds across portions of the Aleutians, Mon, Mar 25.
- High significant wave heights for coastal portions of mainland Alaska, Fri, Mar 22.
 
Detailed Summary:

Recent heavy rain and snow melt is contributing to flooding over parts of the Northern Plains into 
the Upper Mississippi Valley and the Upper Great Lakes through Sunday.  In addition, earlier snow 
melt and rain moving southward from the Upper Mississippi Valley into portions of the Middle and 
Lower Mississippi Valley producing flooding near the river and tributaries through Sunday.  In the 
meantime, upper-level energy over the Southwest/Great Basin that will be reinforced by additional 
upper-level energy over the Central Plains on Monday, before moving eastward to the Southeast by 
Tuesday.  The associated front will move across the Southern Plains into the Southeast also by 
Tuesday.  The system will produce showers and thunderstorms across the region but at this time 
there is no signal that there will be heavy rain but the possibility is there through Tuesday.  
There is a greater signal with a storm moving inland on Tuesday, over California, that there will 
be a region of heavy precipitation greater than one inch or more on Tuesday over Northern 
California.  A weak plume of moisture accompanying the system will begin to move into the 
California Coast overnight Monday into Tuesday.  The energy and the plume of moisture will aid in 
producing an area of precipitation greater than one inch over parts of Northern California.     

In Alaska, deep low pressure moving into the Gulf of Alaska on Friday into Saturday and the 
associated tight pressure gradient will aid in producing high wind of 50 kt or greater over parts 
of the Alaska Peninsula to the Kenai Peninsula on Friday.  In addition, the long fetch over the 
North Pacific/Gulf of Alaska associated with the storm and the high wind will aid in producing an 
area of significant waves of 20 feet or more from the Kenai Peninsula to Kodiak Island on Friday.  
An associated plume of moisture will stream into coastal regions of the Gulf of Alaska and the 
Alaska Panhandle on Friday and Friday night. The storm and moisture will aid to produce an area of 
heavy precipitation over portions of the Alaska mainland from Kodiak Island to the Kenai Peninsula 
on Friday into Monday.  On Monday another storm moving over the Aleutians will aid in producing 
high wind over the Aleutians to the beginning of the Alaska Peninsula due to the strong pressure 
gradient associated with the deep low over North Pacific/Bering Sea.    

Ziegenfelder