Posted at 2:28 PM on February 22, 2011
by Craig Edwards
Filed under: Winter
Satellite image from GEOS from about 1PM CST. Snowcover is somewhat masked by increasing clouds near the Iowa border from Fairmont to Caledonia. The visible images have much better resolution than years ago. You can clearly see the Minnesota River.
When I would give tours to school childern I would animate the images to highlight how the clouds move, but the snowcover doesn't. That is, unless temperatures are well above thawing and the snow is melting rapidly.
With regard to snowfall measurements and how they are officially tallied: Here is the directive from the National Weathe Service:
Measure and record the greatest amount of snowfall that has accumulated on your snowboard (wooden deck or ground if board is not available) since the previous snowfall observation. This measurement should be taken minimally once-a-day but can be taken up to four times a day, (every 6 hours) and should reflect the greatest accumulation of new snow observed (in inches and tenths, for example, 3.9 inches) since the last snowfall observation.
Snowfall amounts can be measured hourly or at any interval as long as the snow measurement board is NOT cleared more frequently than once every 6 hours.
In short, snowfall and snow depth needs to be measured once a day at 6AM. Observations taken at 6 hour intervals are most representative of actual snowfall.