Unsettled weather expected for parts of the Western U.S....
Temperatures will be 10 to near 15 degrees above average over parts of the Southern High Plains...
A quasi-stationary front extends from the Mid-Atlantic Coast westward to the Northern High Plains and southwestward into the Great Basin will remain over the region through Tuesday.
Upper-level energy rotating into the Great Basin will aid in producing light rain and morning snow at some of the highest elevations of the Pacific Northwest eastward to parts of the Northern High Plains from Sunday evening to Monday morning.
On Monday the rain will continues over parts of the Pacific Northwest into the Northern High Plains with regions of showers and thunderstorms over parts of the Northern Rockies/Northern High Plains by Monday evening.
Rain will expand into parts of the Northern Plains by Tuesday morning with snow developing over parts of the Northern Plains to parts of the Great Basin/Sierras.
Meanwhile, low pressure over Northern New England will aid in producing light rain over parts of the area through Tuesday morning.
In addition, upper-level energy will aid in producing light rain over parts of the Central Appalachians on Sunday evening.
A new area of rain will develop over the Upper Mississippi Valley/ Upper Great Lakes into the Ohio Valley very early Monday morning that will move eastward to the Central Appalachian/Mid-Atlantic by Monday evening.