Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Fri Mar 22 2024 Valid 12Z Fri Mar 22 2024 - 12Z Sun Mar 24 2024 ...Heavy snow likely for portions of the Lower Great Lakes and interior Northeast... ...A wet weekend ahead for the East and West Coasts... ...Significant Winter Storm likely across the Northern Plains and into the Upper Midwest late this weekend into early next week... A developing low pressure system will produce snow showers across parts of the Midwest and Upper Great Lakes today. This same system will shift into the Ohio Valley this evening and dump a swath of heavy snow from downwind areas of Lake Ontario into much of central/northern New England. Snowfall totals of 6-12 inches are expected by Sunday morning for those areas. A second system will track across the Gulf Coast and dump showers and thunderstorms over the Southeast and into the Mid-Atlantic today/tonight. Heavy rainfall within scattered to isolated thunderstorms will spread across the Carolina coast and up the Mid-Atlantic to Northeast urban corridor where 1-3 inches of rainfall are possible with isolated higher amounts. A Slight Risk of Excessive Rainfall leading to Flash Flooding (level 2/4) is in effect from southern Maryland and the DC Metro area up the coast through Philly, NYC and into Boston's metro on Saturday. A third system in the Gulf of Mexico will propagate toward the Straits of Florida where it will stall out later today. Anomalous moisture from the subtropical Pacific will join with moisture from the Gulf of Mexico to produce heavy to Excessive Rainfall as well as strong to severe thunderstorms over extreme southern portions of Florida this afternoon and evening. Thus, Slight Risks of Excessive Rainfall (level 2/4) and Severe Thunderstorms (level 2/5) are in effect for this area. Elsewhere, a deep low pressure system will bring unsettled weather to the West this weekend. Heavy rain is likely to focus over coastal areas of northern California into southern Oregon, while heavy snow develops over the northern/central Sierra and Shasta Siskiyous. Anywhere between 2-4 feet of snow are likely for those areas with isolated higher amounts possible. This system will weaken as it moves inland and spreads snow showers across the Rockies on Saturday. By Sunday, this system will begin to redevelop over the Front Range into a significant Winter Storm. Kebede Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php