Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 141 PM EST Thu Nov 28 2024 Valid 00Z Fri Nov 29 2024 - 00Z Sun Dec 01 2024 ...Heavy snowfall in New England expected into Friday morning... ...Lake Effect snows continue and will expand and intensify greatly with time; warnings are in effect... ...The coldest air mass since mid to late February becomes entrenched for most spots east of the Rockies into the weekend... A dynamic mid-latitude cyclone tracks near the New England coast Thursday night before moving into Atlantic Canada on Friday. A swath of moderate to heavy snowfall is likely to develop across portions of the interior Northeast -- winter storm warnings are in effect from eastern New York through central and northern New England where over one foot of fresh snow is possible. Disturbances aloft will send reinforcements to the cold air mass east of the Rockies with a strong and cold surface high nosing into the Plains. It is expected to be the coldest air mass since mid to late February across the Northern Plains and Midwest; wind chills should fall below zero, perhaps as low as -40F in North Dakota on Friday and Saturday. Daily record cold low and high temperatures are possible between the Upper Ohio Valley and southern Appalachians from Friday into Monday, where the cold is most anomalous for late November and early December. In and near northeast Missouri and southern Illinois, a swath of light to moderate snow is expected to fall on Saturday, which would lead to minor impacts for cities such as St. Louis and Evansville, Indiana. Lake effect snows, ongoing across portions of Michigan, should expand and intensify downwind of all Great Lakes as the increasing cold within cyclonic low level flow interacts with record warm Great Lakes temperatures for late November. Thundersnow is possible in some spots. Snowfall totals up to 3 inches in an hour are possible. The snowfall accumulations will be significant through Saturday, up to 5 feet of snow is forecast downwind of Lake Ontario in northern New York which could receive a moisture fetch off three of the Great Lakes. Winter Storm and Lake Effect snow warnings are in effect for areas downwind of the Great Lakes. Florida will remain mild to warm, and winds remain mostly off warm, but slowly cooling, waters of the Gulf of Mexico and the westernmost Atlantic. Roth/Kedebe Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php