GCIP LSA-NW 2000 NCDC Hourly Precipitation Data in QC format
     
     1.0  General Description
     
          This Hourly Precipitation Dataset is one of several precipitation
     datasets provided in the GEWEX Continental-Scale International Project
     (GCIP) Large Scale Area-North West (LSA-NW) Enhanced Annual Observing 
     Period (EAOP) 2000. This precipitation dataset was formed from one data 
     source (i.e. National Climatic Data Center (NCDC) hourly precipitation 
     dataset (TD 3240)). Data from this source was quality controlled. This 
     dataset contains data for the GCIP LSA-NW EAOP-00 domain and time period 
    (01 April 2000 through 31 March 2001). The GCIP LSA-NW EAOP-00 domain is 
    approximately 90W to 115W longitude and 36N to 51N latitude.
     
     2.0  Detailed Data Description
     
     2.0.1 NCDC Hourly Precipitation Algorithms
     
          The NCDC Hourly Precipitation dataset (TD 3240) is formed by
     retaining both incremental and accumulative precipitation values from the
     raw precipitation data. Both incremental and accumulative values are
     contained in the GCIP/LSA-NW Hourly Precipitation Dataset. If an 
     accumulation period began prior to but continued into the beginning of the 
     GCIP LSA-NW 2000 time period, the precipitation values in that
     accumulation period were reset to missing values. An accumulation period
     that began near the end of the GCIP LSA-NW 2000 time period, but
     continued after the end of the GCIP LSA-NW 2000 time period would
     also have its precipitation values reset to missing. For more information
     on the NCDC Hourly Precipitation dataset, TD 3240, see NCDC, 1986.
     
     2.1  Detailed Format Description
     
          The GCIP LSA-NW 2000 NCDC Hourly Precipitation data contains seven
     metadata parameters and three data parameters. The metadata parameters
     describe the date/time, network, station, and location at which the data 
     was collected. The three data parameters repeat once for each UTC hour from
     0000 through UTC hour 2300. Data reported for a designated hour
     represents data collected during the previous hour. All times are reported
     in UTC, and precipitation data values are reported in millimeters. A
     Quality Flag and a QC Code are assigned to each data value during the
     University Corporation for Atmospheric Research/Joint Office for Science
     Support (UCAR/JOSS) Quality Control (QC) processing. For a list of
     possible Quality Flag and QC Code values see the Quality Control Section
     3.0.  The table below details each parameter.
     
     Parameters               Units
     ----------------------   ----------------------------------
     Date of Observation      UTC 
     Time of Observation      UTC 
     Network Identifier       Abbreviation of platform name 
     Station Identifier       Network Dependent 
     Latitude                 Decimal degrees, South is negative
     Longitude                Decimal degrees, West is negative 
     Station Occurrence       Unitless 
     Hourly Precip Value      Millimeters 
     Quality Flag             See list of Definitions 
     QC Code                  See list of Definitions 
     
     
     2.2  Data Remarks
     
     
     3.0  Quality Control Processing
     
          This precipitation data set was formed from National Climatic Data 
     Center (NCDC) hourly precipitation dataset (TD 3240)
     
          Gross limit checks were used to determine the quality of the data
     in the GCIP LSA-NW 2000 NCDC Hourly Precipitation data set. Data values less 
     than 20 millimeters were flagged as good. Any data value greater than or equal
     to 20 millimeters but less than 50 millimeters was flagged as questionable.
     Any data value greater than or equal to 50 millimeters was flagged as
     unlikely. Several questionable and unlikely data values were also manually
     inspected.  After inspection, the quality control code and flag may have
     been manually updated to better reflect the likelihood of the actual
     occurrence of the precipitation value based on an isohyet analysis.  
     The data were never changed, only flagged. Tables 1 and 2 contain the 
     quality control codes and flags, respectively. 
     
     Table 1
     
     Quality Control Flag          Description
     ---------------------------   --------------------------------------------
     0                             No qualifier required 
     1                             Accumulation period
     2                             End of Accumulation period
     3                             Deleted value. Original data was unreadable.
     4                             Trace of precipitation.
     5                             Probable amount as a result of melting frozen
                                   precipitation.
     6                             Suspect amount relative to time or period of
                                   occurrence.
     7                             Missing value
     
     Table 2
     
     QC Code             Description
     -----------------   ------------------------------------------
     U                   Unchecked
     G                   Good
     M                   Normally recorded but missing
     D                   Questionable
     B                   Unlikely
     N                   Not available or Not observed. 
     X                   Glitch
     E                   Estimated
     C                   Reported value exceeds output format field
                         size or was negative precipitation.
     T                   Trace precipitation amount recorded.
     I                   Derived parameter can not be computed due
                         to insufficient data.
     
     4.0  References
     
     National Climatic Data Center, 1986: Hourly Precipitation Data, TD 3240. 
          National Climatic Data Center, Asheville, NC, 20 pp.