BOX AFD:
"It is Fri night into Sat night where the confidence in the forecast really starts to dwindle. Recent deterministic global model runs have showed varying solutions both in track and strength pertaining to a developing coastal storm near the SE US coast, induced by a potent shortwave trough along the Gulf Coast or Carolina coast. The deep amplitude and location of the longwave trough near the western slope of the Appalachians in most models indicates an inland track is a less favored outcome. This is reflected in GEFS/GEPS/EPS ensemble mean low track being more offshore near or SE of the 40N/70W benchmark. Only a small minority of individual members show an inland track; while most members reflect a coastal/offshore track, there`s large spread in the members in terms of how close to the SNE coast the storm may get. Have mention of PoP across all of SNE for Fri night into Sat night; but sided PoP to slight or low chance northwest of I-95; then to more solid Chance (30-40%) near the coastal plain to the offshore waters. This isn`t the final answer, and expect changes to come to these as well. However this should be a good starting point with adjustments up or down as more coherent and consistent trends develop in the coming days. What we can say is that it is looking like a coastal storm should be somewhere either over the Eastern US coast or offshore in the Fri night to Sat night timeframe, but it`s far too uncertain to lock into any solution given the location and strength spread in the ensembles. Sunday however looks dry or with improving conditions but uncertainty from Fri-Sat night lingers into Sunday too. Stay tuned!"