Fig. 1—Vieu showing location of rain-sampling pans.
data and radar observations of movement of precipitation areas and
height of echo tops.
Rainfall-rate data were obtained by a tipping-bucket recording
rain gauge. This instrument records an event mark ona Strip-chart
recorder after every 0.01 in, of rain. Thedata were used to provide the
detailed time record of rainfall rate. The variations observed in these
records indicate the basic character of the rain and help to resolve the
fine structure of the rain system.
Maximum heights of radar echoes were obtained from the hourly
reports of the operator of the WSR-57 radar at the U. S, Weather
Bureau Station at the Detroit Metropolitan Airport, which is located
about 8 nautical miles east of the sampling station, It was found that
the Weather Bureau radar observations were best suitedto a qualitative
classification of the precipitation system (i.e., squall line, stratiform
area, etc.); this information has been incorporated into the description
of each rain.
SAMPLE ANALYSES
Radiochemical Analysis
The radiochemical analysis procedure consisted of the following
steps: The sample was pumped through a graduated series of filters to