Network description and datafile format

Volunteer Farmer Precipitation Network Description and File Format

Daily precipitation measurements were collected by volunteer farmers during the months of June,July and August for the period 1975 to 1983. A TRU-CHEK wedge type rain gauge was provided toeach of the volunteers and they were asked to record the accumulated precipitation at approximately 08:00 each morning. The precipitation network incorporated an area within 80 mile radius of the radar site. The number of stations varied from year to year and are summarized below.

Year Number of Stations

1975 434 1976 459 1977 492 1978 503 1979 438 1980 485 1981 500 1982 570 1983 549

File Format

Filename: PRYYYY.dat

Each record in the file summarizes the daily precipitation for the months of June through August for a particular station. A station record occupies 6 lines; the first line contains the station identifier, the legal land description, the month and the first 15 days of data for June; the second line contains the remaining 15 days of June; the third line contains the month and the first 15 days of data for July; the fourth line contains the remaining 16 days of July; the fifth line contains the month and the first 15 days of data for August; the sixth line contains the remaining 16 days of July. The format is as follows:

Line Format

1 1X,A3,6X,A2,3(I2),I1,2X,I2,3X,15I3 2 26X,15I3 3 21X,I2,3X,15I3 4 26X,16I3 5 21X,I2,3X,15I3 6 26X,16I3

The daily precipitation data are recorded in inches and occupy 3 spaces. For example, a coding of 142 is equivalent to 1.42 inches. The code '777' represents trace precipitation. The code '888' indicates that the operator was not at home to record the accumulated precipitation. At the end of a series of '888' codes, the accumulated total is given for that period. The true amount may be higher than the measured amount since evaporation losses may have occurred. A code of '999' represents missing data. An example of one record within a file is given below:

B22 NE2247045 6 000035007000000016000000002001030000000000000 015003000026040022000001000000000004000000000 7 000999000000050007008000000000000000034275032 888888888888888888256020888888003006019010000000 8 000000000000000000000000000000000000000000000 000000000000000000000000000000000000005000000000

Where B22 is the station identifier; NE2247045 the legal land description; 6, 7, and 8 represent the months of June, July and August. There was 0.03 inches of rain reported on June 2. An example of total precipitation recorded after several days of absence is shown during the month of July where between July 16 and 21, 2.56 inches of rain was measured (and reported on July 22). The distribution of the total amount is unknown.

- C.G. Ewing and B. Kochtubajda