How Much Rain Actually Fell Across Northern Ohio?

If we took all of the rain this past weekend across northern Ohio and calculated the volume in gallons, how much would we have?

First, I eyeballed the area across northern Ohio that received roughly 3/4" of rain by late Sunday morning. The area is 16,000 square kilometers (6200 square miles)...

The area that received roughly 1.5" of rain was around 2000 square miles...

The smaller area that received at least 2.5" wasa little under 400 square miles.

Convert the "square miles" to "square feet" for each area: 

6300 square miles = 173 BILLION square feet  (3/4" rain)
2000 square miles = 56 BILLION square feet (1.5" rain)
400 square miles = 11 BILLION square feet (2.5" rain)

First, I calculated the volume of water for the area that received 3/4" of rain:

Volume = length x width x height  or AREA x height

VOLUME 1 = 173 BILLION square feet x 3/4" rainfall (0.0625 ft) =
roughly 11 BILLION cubic feet

In order to not double count volumes, I subtracted the starting 3/4" from the second 1.5" to get the HEIGHT for the volume calculation of the second area

VOLUME 2 = 56 BILLION square feet x (1.5" - 3/4") rainfall or 0.0625 ft = 
roughly 3.5 BILLION cubic feet

I subtracted second 1.5" from the third 2.5" to get the HEIGHT from the volume of the third area.

VOLUME 3 = 11 BILLION square feet x (2.5" - 1.5") rainfall or 0.083 ft =

roughly 886 MILLION cubic feet

Add the volumes together, we get: ~15.2 BILLION cubic feet

Convert CUBIC FEET to GALLONS gives us:  ~114 BILLION GALLONS

That's alot of water!