I have used weighing the exterior CoCo gauge for years and it works perfectly. First, weigh the gauge empty, excluding the inner tube and the top—make sure it is clean from debris. In my situation, it weighs 460 grams. When measuring precipitation in the gauge, snow or rain, weigh it. Then deduct the weight of the gauge itself and the result is then divided by 201 to get inches of water. For example, I get up in the morning and get the CoCo gauge, bring it inside, snow and all, then weigh it. If it weighs 500 grams, subtract the weight of the gauge itself (460 grams) results in 40 grams of water content in the CoCo gauge. Divide the 40 by 201 gives you .199 inches of water, rounded, .20. This works year round and is quite simple to calculate.