Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Thu Nov 02 2017 Valid 12Z Thu Nov 02 2017 - 12Z Sat Nov 04 2017 ...Colder and unsettled weather to arrive across the Pacific Northwest and northern Rockies through the end of the week with heavy mountain snowfall anticipated... ...Heavy rains are expected to arrive across northern California by this weekend... ...Warmer temperatures are expected for the southern and eastern Unites States over the next couple of days... The main theme over the next couple of days will be a transition to unsettled and stormy weather across much of the Pacific Northwest, the northern Rockies and parts of the northern Plains as a strong trough of low pressure arrive across the Northwest U.S. and ushers in some substantially colder temperatures and also a broad area of precipitation including heavy snowfall. Some of the heaviest snowfall will occur over the Cascades and into Bitterroots of the northern Rockies. Some heavy snowfall is also expected to streak out across parts of the northern Plains through the end of the week as low pressure gradually traverses the Intermountain West. Temperatures across some of these areas are expected to fall to as much as 20 degree below normal by the end of the week. By this weekendm, expect heaviest rains with the same storm system to impact northern California. Meanwhile, the weather for the next couple of days will be much warmer across the southern and eastern U.S. as southerly flow ahead of a cold front will allow warmer temperatures and a touch of humidity to return north from the Gulf Coast states. Temperatures will be locally as much as 10 to 20 degrees above normal. A frontal zone moving across the Midwest will move toward the Ohio Valley and will help focus an axis of showers and possibly a few thunderstorms. The heaviest of the rain should tend to focus over the Great Lakes region as low pressure traverses the region. In the wake of the cold front moving off to the east, temperatures will be cooling off to near or slightly below normal. Orrison Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php