"Light snow" is an indication of rate of snow fall. "Under 1 inch" is an indication of accumulation. They don't necessarily have any relation to eachother and neither is an direct indication of the other.
Example: you can have one inch of heavy snow or one inch of light snow. Different rates, same accumulation.
If I was due to have light snow later tonight, accumulating around one inch, I would rather the complication say "under 1" snow later" or "Light snow tonight, >1" or just "light snow later" or something to that effect. Not something long and drawn out that won't fit on the screen.