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NATIONAL WEATHER SERVICE
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equivalent of the snowfall.
     As winds increase, gauges collect less and less of the precipitation that actually falls. Generally speaking, the stronger the wind and the drier the snow, the less is captured in the gauge. If you notice that less snow is in the gauge than accumulated on the ground, you should first empty any existing snow from inside the 8-inch cylinder, then use it to take a snow sample, sometimes referred to as "take a core" or "cut a biscuit" from your snow board with the 8-inch overflow can. Melt the biscuit of snow, pour the liquid into the small measuring tube to measure the water equivalent.
     Measuring snow via a snowboard works well in areas with little or no wind.  In Maine however, we often deal with wind driven snow...in these cases the illustrated snow measuring method works best.

     Measuring snow accurately can be difficult, especially when it is windy. Here are guidelines to help you measure the snowfall.

     To measure new snow, measure snow in an area that was clear of snow previous to the start of the current snowfall. You should use a ruler or yard stick and take an average of multiple measurements.  Do not stick the measuring stick too deep into the grass.  Try to get 5 or 6 measurements from various locations and then take the average.  If it is windy, choose an area that is not in a snow drift and is not in a place where the wind has blown the snow so that the ground is bare.  Use good judgment in selecting an area where the snow is least affected by the wind.

     When strong winds have blown the snow, take several measurements where the snow was least affected by drifting and average them. If most exposed areas are either blown free of snow while others have drifts, again try to combine visual averaging with measurements to make your estimate.

Measuring the water equivalent of snowfall since the previous day's observation.

     This measurement is taken once-a-day at your specified time of observation. Melt the contents of your gauge (by bringing it inside your home or adding a measured amount of warm water) and then pour the liquid into the funnel and smaller inner measuring tube and measure the amount to the nearest .01 inch (use NWS provided measuring stick) just as you use for measuring rainfall. Do not measure the melted precipitation directly in the large 8-inch outer cylinder. Make sure the inner measuring tube can't fall over when pouring the liquid back into it. If the melted water equivalent (including any added warm water) exceeds two inches and cannot fit into the measuring tube all at one time, then empty the full measuring tube and pour the remaining liquid from the large 8-inch outer cylinder into the emptied measuring tube. Then, add and record the water equivalent of the multiple measurements.
     If you added warm water to the gauge to melt the snow, make sure you accurately measure the amount of warm water added before pouring it into the gauge. Then, when you take your liquid measurement, subtract the amount of warm water added from the total liquid measurement to get your final liquid water

Do not measure drifts, but do measure from several locations where the snow appears to be least affected by drifting.  Average these readings to arrive at your depth.

Measure each new snow.   Use good judgment in selecting spots least affected by drifting.

If all snow melts as it falls, then enter a Trace

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