Training Guide in Surface Weather Observations - Multiple Choices

When finished, put the emptied measuring tube
back inside the empty outer can and replace the
funnel on top.
During the season when frozen precipitation
(except hail) or freezing temperatures are likely
to occur, remove the funnel and measuring tube
from the outer can. This will allow for the
measuring of the water equivalent of frozen
precipitation. Follow the procedure in paragraph
8.2.2.4d to obtain this measurement.
8.3.2 Universal Recording Weighing Gauge
The weighing-type recording gauge (see Figure
8-2) is designed to record the rate and amount of
precipitation. These gauges consist of a receiver
with an inside diameter of exactly 8 inches that
funnels precipitation into a collector mounted on
a weighing mechanism. The weight of the
precipitation in the collector compresses a spring,
which is connected to a pen (ink) arm. Ink from
the pen leaves a trace on a paper chart, which is
wrapped around a clock-driven cylinder. The
cylinder rotates continuously, making one
revolution every 24 hours. Ink tracings on the
chart provide a “history” of precipitation rates
and amounts.
8-6
Figure 8-1. 8-Inch Non-Recording Gauge.
Charts are graduated to the nearest .05 inch and may be read to the nearest .01 inch by interpolating
between the graduations. The total capacity of the gauge is 12 inches, although the chart is graduated
to only 6 inches. When the 6-inch mark is reached, the pen of the chart reverses direction. The reverse
in pen direction is commonly referred to as “dual traverse.”
During the season when frozen precipitation (except hail) or freezing temperatures are likely to occur,
winterize this gauge as follows:
a. At the start of winter, remove the funnel from the collector. Snow rings (on some universal
gauges) should be installed in place of the funnel.
b. Empty the bucket or collector and replace it in the gauge.
c. Turn the adjusting knob so the pen reads zero on the chart.
d. Pour one quart of propylene glycol antifreeze into the bucket. Do not use commercial antifreeze
or add water.
e. Make no adjustments to the gauge after the antifreeze has been added. The pen should rest
between the 1 and 2 inch lines after antifreeze has been added.