Here is a simplified list of steps for taking a complete daily climatological observation of precipitation and snow. A detailed discussion of each component of the observation then follows. The lists of special concerns and precautions that accompany each item are very important. Keep in mind that weather conditions at the time of observation may make it impossible or inappropriate to follow these steps in this precise order. Use common sense and good judgment.
Some instructions include the words "measure and determine." In the
observation of snow, a single measurement at the time of observation
may not be sufficient to accurately assess snowfall or depth. It may
be necessary to "determine" these quantities by using additional
information such as the average of many measurements or measurements
taken at previous times during the day.
Steps in completing a daily climatological precipitation and snowfall
observation:
1. Measure and determine the amount of snowfall for the previous 24
hours.
2. Measure and determine the total depth of snow on the ground (the
sum of both the old snow, plus any new snow that has accumulated) at
the scheduled time of observation.
3. Measure the amount of precipitation that has accumulated in the
precipitation gauge during the previous 24 hours.
4. Measure the water content of the new snow that has accumulated on
the ground during the previous 24 hours.
5. Measure the total water content of both old and new snow on the
ground.
6. Record all observations, using the appropriate units, on a
climatological observation form. Make certain that the form contains
all necessary information to accurately identify the correct weather
station, day, month, and year. Double check all entries for accuracy
and consistency. Include descriptive remarks.
7. If previously arranged, transmit observation by phone or computer
to the National Weather Service, local media and/or other interested
sources.