The Present Weather Detector is a serial sensor. The MET system datalogger reads in the
data from this sensor. During the time in question serial comms problems were causing the
data from the sensor to be read incorrectly. The data for one variable showed up in
data for another variable or not at all. We reprocessed the data to correct as much of this
error as we could. The cumulative rainfall variable was calculated from the
instantaneous rainfall variable during reprocessing. Since we cannot be entirely sure all
cumulative rainfall values are correct or were completely captured the cumulative rainfall data is
considered to be unreliable. This issue shows up when comparing the cumulative rainfall
data at the end of the day 07/31/2006 (79.08) and the beginning of the next day
08/01/2006 (3.17). Clearly we were either under or over-estimating the cumulative rainfall. |