Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 254 PM EST Mon Dec 28 2020 Valid 00Z Tue Dec 29 2020 - 00Z Thu Dec 31 2020 ...Heavy snow for parts of the Northern/Central Plains and Midwest through Wednesday... ...Heavy snow for parts of the Great Basin and Central Rockies... ...Rain/Freezing rain over from the Central Plains into the Midwest through Wednesday... An upper-level low will amplify as it cuts into the Southern Rockies over the next two days. This will lead to the development of a potent mid-latitude cyclone over the Central/Southern Rockies. This low pressure system will produce heavy snow over parts of the Central/Colorado Rockies tonight. Winter Storm Warnings and Advisories are in effect for those areas. Heavy snow and freezing rain will spread over the Northern/Central Plains and Midwest through Tuesday as the surface low moves into the Southern Plains. Winter Storm Watches, Warnings and Advisories are in effect from the Northern/Central Plains into the Middle/Upper Mississippi Valley as a result. Heavy rain may develop over Oklahoma/Texas Tuesday night into Wednesday as the associated cold front sweeps through the region and taps into a sufficient stream of Gulf moisture. Scattered to isolated thunderstorms may develop across the Southern Plains and Lower Mississippi Valley Tuesday night into Wednesday as instability rises along the cold front. Snow and freezing rain will spread into the Great Lakes area during this same period. Snow maybe particularly heavy over parts of the Upper Great Lakes on Wednesday. This system will go on to impact the East Coast later this week. Meanwhile, another deep area of low pressure will impact the Pacific Northwest starting Tuesday night. This system is expected to bring heavy snow to the Cascades and Olympics and rain to the lower elevations. Kebede Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php