"Some areas have seen over 2" of rain so far with even more to come.
A Flood Watch will be in effect for the region Saturday through Sunday. However, it appears that flooding for rivers and larger streams is unlikely, and will probably be limited to brief and minor flooding of roads and small streams even where there is heavy rain for a couple hours. There should be a lull in the rain before more arrives for Saturday evening.
Rain will be off and on Saturday night into Sunday, with milder conditions settling in.
The flood threat is expected to end for north Alabama late Sunday afternoon from west to east as a front pushes through. With respect to the Mercedes Marathon, I can't make any promises in this kind of setup but some of the forecast data suggests the rain could temporarily thin our around start time Sunday morning.
"We could potentially have basically a whole month's worth in just a few days", said Sarah Johnson, a meteorologist at the National Weather Service station in Mount Holly.
WTOP's Dave Dildine said that the area has seen a precipitation deficit of about 5 to 8 inches, and the weekend rain may help steer the area out of its severe drought status.
There is a slight chance that the rain will begin before noon Saturday, though rain is likely to occur after 1 p.m., becoming heavy at times. Since there will be occasional breaks in the rain, access to FOX 5 Live VIPIR, hour-by-hour forecasts, and precipitation/lightning alerts can help you plan around the rain.