As of the latest model runs, the NAM is starting to show signs of a more periodic rainfall for late Friday and Saturday in our area.
Notice how by 4 PM Friday evening, the GFS model shows steady rainfall heading into S. Ohio and just touching N.E. Kentucky. The green colors are even indicating heavier rainfall in S. Ohio at that time. Quite the contrary with the Nam model for this time period. It shows steady rainfall further North, and just barely touching S. Ohio. Much of West Virginia is looking dry with small rainfall chances into Kentucky. Furthermore, the rainfall is looking to be light with virtually no signs of heavy rainfall as is thought by the GFS.
For 1 PM Saturday, the GFS shows a large swath of rainfall stretching from N. Pennsylvania and into the Plains. Heavy rainfall is indicated with the orange/green colors for S. Ohio and far N.W. West Virginia (outside of our viewing area the GFS is indicating even heavier rainfall for areas further west). According to the GFS, all of the tri-state region will see persistent rainfall during this time period. This is not the case with the NAM model for 1 PM Saturday. The rain band is broken up and patchy. There is no indication of heavy rainfall for our area and at most, we will see periodic light rainfall at this time.
At this point, I am leaning toward the NAM and the likelihood of patchy/inconsistent rainfall for Saturday in most of our area (with the exception of S. Ohio). The NAM does a good job of accounting for things like downslope, which may come into play Saturday with southwesterly winds turning slightly southeasterly.
As for Sunday, this is the current forecast from the GFS...
We should be seeing the heaviest rainfall in our area on Sunday. Notice the dark green and yellow colors in the picture above which show higher rainfall amounts in S. Ohio this day (poor Ohio is looking to get slammed) and also in S. West Virginia and Kentucky.
Also, I wouldn't be surprised if we saw a few flurries heading into Monday afternoon for the WV mountains. The yellow line crossing through the middle of the picture indicates the location of the 5400 m thickness line for the 1000-500 mb level. This line, which is cutting through central WV during the 1 PM Monday time frame, indicates the likelihood of precipitation falling as snow. We may even see a dusting overnight Monday into Tuesday as cool air continues to usher into our region. This will be monitored over the next couple of days.
Lastly, take a look at the expected rain totals from the HPC...
With the front stalling over Ohio, we are seeing high rainfall totals throughout the state. Areas like Cincinnati could see 4-6 inches! S. Ohio should stay in the 1.5-2.5 inch range. Regardless, folks in Ohio should prepare for the likelihood of small flooding, especially toward central and western Ohio. West Virginia and E. Kentucky should see about 1.0-1.5 inches.