No online gauge, but the Big Sandy's Rockville gauge may be a rough guide. Look for a rising gauge that eclipses 7.5 ft. and get there fast. This is most likely to still be running if the rain is still falling. Also, if you are in the Albright, WV area and running out of options because of high water, this one might be there for you. The AFWS Rain Gage
can give you an idea; closest would be Afton (3901). You'll probably need an inch of rain in a 24-hour period.
There is a painted gaige on the Rt. 28 bridge over the creek, which provides surgy readings. A reading of 6 inches or less *might* seem bumpy at the top and OK on down. A foot is plenty healthy, especially in the steeper top parts, and 1.5 feet is getting pushy.