A deep upper-level low churning over the West Coast will continue aiding in an influx of moisture extending from the eastern Pacific through the Intermountain West through the next few days.
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A particularly intense surge of moisture on Tuesday is forecast to produce more widespread heavy rain along the central/southern California coasts and nearby mountain ranges.
Several inches of rain across the Transverse Ranges may lead to more widespread instances of flash flooding, with areas near and within recent burn scars most as risk.
Urban regions could also experience downpours capable of producing rapid runoff and ponding water on roadways..
Meanwhile, higher elevations along the Sierra will also see plentiful moisture associated with the strong southwest flow.
Precipiation will fall as snow in these higher elevations, with upwards of over 3 to 4 feet across southern parts of the Sierra Nevada.
Winter Storm Warnings have been issued to further highlight the threat of extreme winter conditions.
Farther inland, moderate to heavy rain is possible across parts of the central Great Basin, with heavy snow in the higher terrain.
This stream of atmospheric moisture will also continue to flow along a cold front and into the northern Rockies through midweek as well.
Heavy mountain snow is forecast to extend from central Nevada and Utah to the Yellowstone region of southern Montana, western Wyoming, and eastern Idaho.
Farther east and into the northern Plains and Upper Midwest, a lifting warm front will spark numerous showers and thunderstorms beginning Tuesday night from central Minnesota to the shores of Lake Superior.
As multiple rounds of storms pass over similar areas, a few isolated flash floods cannot be ruled out.
It is also along this boundary where a rapidly developing low pressure system may lead to blizzard conditions across the northern Plains on Thursday.
Florida and the Southeast coastline are expected to contend with impacts associated currently named Subtropical Storm Nicole as early as late Tuesday.
A very large wind field surrounding Nicole aided by a strong high pressure system over the Great Lakes and eventually the Northeast by Wednesday will funnel strong east-northeast winds into the Atlantic coastline of Florida and the Southeast.
Combined with astronomical high tide, coastal flooding and rough surf is expected to be a widespread concern for these regions.
Impacts more associated with the center of Nicole are expected to near southeast Florida Wednesday morning in the form of strong winds and heavy rain.
Hurricane and Tropical Storm Watches have been issued from southeast Florida to coastal Georgia.
As far as the temperature outlook for the Nation over the next few days.
Well above average temperatures with highs into the 70s and 80s are forecast across much of the central U.S., extending into the Midwest on Wednesday.
Conversely, frigid conditions are expected throughout the northern High Plains of Montana and parts of the northern Great Basin.
An arctic airmass nosing southward from western Canada will spread widespread subfreezing highs into the region, with lows below zero across northwest Montana. ■