I’ve heard that an inch of rain would fall as 10 inches of snow. Is that always true?
That may be the case sometimes, but it cannot be used as an absolute conversion. The ratio of liquid or melted precipitation to the amount of snow received can vary quite a bit depending on vertical profiles of temperature, moisture, upward vertical motion, and instability. A common liquid to snow ratio in central Iowa is 13:1 (13 inches of snow for every inch of liquid precipitation) with research showing about half of our snow events occurring with ratios between 9 and 15 to 1. However outlier events have occurred with ratios in the single digits and well into the 20s. Heavy wet snows typically have lower ratios, while higher ratios are more favorable during fluffier snows when the atmosphere is relatively cold.
