Heavy rain and flash flooding is expected Friday with thunderstorms along the Gulf Coast and into the southeast. Moderate to heavy snow is expected from the Tennessee Valley into the Appalachians. Light to moderate snowfall is expected from the Upper Midwest into the Great Lakes.
Gulf Coast into the Southeast: By Friday the low pressure system is expected to track out of the Gulf and into the Southeast states, leading to widespread showers and thunderstorms with a heavy rainfall potential. Generally 2 to 3 inches will be possible, though some locations may see upwards of 4 inches. Flash flooding will be possible.
Tennessee Valley into the Appalachians: Much of this region will likely be above freezing on Friday morning, allowing precipitation to fall mainly as rain. However, as colder air moves into the Tennessee Valley through the day and into the evening on Friday a changeover to all snow will be possible. Across the Appalachians a rain/snow/freezing rain threat will be present into Friday evening, before deeper cold air works its way into the region, leading to all snow of 4 to 6 inches, with locally heavier amounts possible, especially for the higher elevations. There are still some uncertainties in regards to the exact track of the low, therefore the precipitation type/amounts above are low confidence at this time.
A Clipper system tracking through southern Canada will push a cold front through the Upper Midwest on Friday allowing for light amounts of snow and a front moving into the Pacific Northwest will allow for light to moderate snowfall for the highest elevations of the Cascades. No major impacts are expected from these events.