Heavy snow over parts of the Southern Plain/Middle Mississippi Valleyon Sunday and over the Northeast overnight Monday into Tuesday.There is a Slight Risk of excessive rainfall over parts of SouthernAppalachians/Southeast into the southern Mid-Atlantic.There is an Enhanced Risk of severe thunderstorms over parts of theWestern Gulf Coast/Lower Mississippi Valley on Sunday; there is a SlightRisk of severe thunderstorms over parts of the Central GulfCoast/Southeast on Monday.Low pressure, an ass...