Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 328 AM EST Sat Jan 13 2024 Valid 12Z Sat Jan 13 2024 - 12Z Mon Jan 15 2024 ...Major winter storm continues with significant impacts over the eastern half of the U.S; more heavy rain in the Northeast through this morning... ...Significant Arctic cold and dangerous wind chills expected through midweek; some snow and ice possible over the Mid-South... ...Heavy rainfall to return to the West Coast this morning... Our very busy weather pattern continues this weekend as an intense low pressure system yields significant wintry weather across the Corn Belt and Great Lakes today, with frigid Arctic air on its heels spilling southward from Canada. As of this morning, surface observations and radar depict moderate to locally heavy snowfall and gusty winds across portions of the Heartland as intense low pressure lifts into the Great Lakes. Bouts of snowfall on the back side of this expansive low, combined with wind gusts upwards of 25-40 mph will maintain blizzard conditions and dangerous to impossible travel across parts of the Corn Belt through the Great Lakes today even as the overall snowfall area associated with this system diminishes by later on this evening. As the system lifts into Canada this afternoon, cold northwesterly flow will rev-up the lake effect snow machine downwind of the Great Lakes, where an additional 12-24 inches of snowfall can be expected where lake effect snow bands focus across much of western Michigan into New York state through midweek. Meanwhile, in the warm sector of this system heavy rainfall is streaming into the Northeast, which may result in scattered instances of flooding through this morning as much of the region is soaked in light of recent heavy rainfall. Coastal areas across portions of the Mid-Atlantic and Northeast can also expect to see moderate to isolated major coastal flooding today, with significant impacts. The weather story is equally busy for the western half of the U.S. as the aforementioned Arctic airmass presses further south and west. Low temperatures approaching 40-50 below zero are not out of the question this morning over parts of Montana in the heart of the cold air, and numerous sub-zero low temperature records could fall today and tomorrow over the Northern and Central Plains. Including wind chill, temperatures will fall below minus 30 over a large area running from the northern Rockies to northern Kansas, with minus 50 possible across the Dakotas. Further west, heavy blowing snow and valley icing will all contribute to hazardous travel across the Great Basin and Pacific Northwest this weekend, where a swath of Winter Storm Warnings and Watches is in effect. Significant freezing rain is expected over Oregon today, with tree and power line damage possible. The cold air migrating south is expected to usher in wintry precipitation over the Mid South by the end of Sunday, with areas of snow, sleet, and freezing rain likely to develop across the ArkLaTex. As we begin the work week, several inches of snow are possible across these areas. Unfortunately, hazardous cold weather looks to stick around going into next week, with dangerously low temperatures and wind chills persisting through at least midweek. Scattered flash flooding also remains a threat today across portions of northern coastal California and Oregon with strong low pressure lingering offshore. Periods of excessive rainfall rates will support rainfall totals of 3-5 inches through today, where a Slight Risk of Excessive Rainfall is in effect. Asherman Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php