This documentation describes the record format for the county files on /pub/data/cirs/climdiv that have the filenames: climdiv-pcpncy-vx.y.z-YYYYMMDD climdiv-tmaxcy-vx.y.z-YYYYMMDD climdiv-tmincy-vx.y.z-YYYYMMDD climdiv-tmpccy-vx.y.z-YYYYMMDD climdiv-cddccy-vx.y.z-YYYYMMDD climdiv-hddccy-vx.y.z-YYYYMMDD nClimDiv COUNTY TEMPERATURE-PRECIPITATION OCTOBER 2018 The major parameters in this file are sequential climatic county monthly maximum, minimum and average temperature (deg. F. to 10ths) and precipitation (inches to 100ths). Period of record is 1895 through latest month available, updated monthly. Values from the most recent two calendar years will be updated on a monthly basis. Period of record updates will occur when the underlying data set undergoes a version change. METHODOLOGY: County values in nClimDiv were derived from area-weighted averages of grid-point estimates interpolated from station data. A nominal grid resolution of 5 km was used to ensure that all divisions had sufficient spatial sampling (only four small divisions had less than 100 points) and because the impact of elevation on precipitation is minimal below 5 km. Station data were gridded via climatologically aided interpolation to minimize biases from topographic and network variability. The Global Historical Climatology Network (GHCN) Daily dataset is the source of station data for nClimDiv. GHCN-Daily contains several major observing networks in North America, five of which are used here. The primary network is the National Weather Service (NWS) Cooperative Observing (COOP) program, which consists of stations operated by volunteers as well as by agencies such as the Federal Aviation Administration. To improve coverage in western states and along international borders, nClimDiv also includes the National Interagency Fire Center (NIFC) Remote Automatic Weather Station (RAWS) network, the USDA Snow Telemetry (SNOTEL) network, the Environment Canada (EC) network (south of 52°N), and part of Mexicos Servicio Meteorologico Nacional (SMN) network (north of 24°N). Note that nClimDiv does not incorporate precipitation data from RAWS because that networks tipping-bucket gauges are unheated, leading to suspect cold-weather data. All GHCN-Daily stations are routinely processed through a suite of logical, serial, and spatial quality assurance reviews to identify erroneous observations. For nClimDiv, all such data were set to missing before computing monthly values, which in turn were subjected to additional serial and spatial checks to eliminate residual outliers. Stations having at least 10 years of valid monthly data since 1950 were used in nClimDiv. For temperature, bias adjustments were computed to account for historical changes in observation time, station location, temperature instrumentation, and siting conditions. Changes in observation time are only problematic for the COOP network whereas changes in station location and instrumentation occur in almost all surface networks. As in the U.S. Historical Climatology Network version 2.5, the method of Karl et al. (1986) was applied to remove the observation time bias from the COOP network, and the pairwise method of Menne and Williams (2009) was used to address changes in station location and instrumentation in all networks. Because the pairwise method also largely accounts for local, unrepresentative trends that arise from changes in siting conditions, nClimDiv contains no separate adjustment in that regard. For additional information on how nClimDiv is constructed, please see: http://journals.ametsoc.org/doi/abs/10.1175/JAMC-D-13-0248.1 STATE CODE TABLE: Range of values of 01-48. 01 Alabama 28 New Jersey 02 Arizona 29 New Mexico 03 Arkansas 30 New York 04 California 31 North Carolina 05 Colorado 32 North Dakota 06 Connecticut 33 Ohio 07 Delaware 34 Oklahoma 08 Florida 35 Oregon 09 Georgia 36 Pennsylvania 10 Idaho 37 Rhode Island 11 Illinois 38 South Carolina 12 Indiana 39 South Dakota 13 Iowa 40 Tennessee 14 Kansas 41 Texas 15 Kentucky 42 Utah 16 Louisiana 43 Vermont 17 Maine 44 Virginia 18 Maryland 45 Washington 19 Massachusetts 46 West Virginia 20 Michigan 47 Wisconsin 21 Minnesota 48 Wyoming 22 Mississippi 50 Alaska 23 Missouri 24 Montana 25 Nebraska 26 Nevada 27 New Hampshire FILE FORMAT: IMPORTANT NOTE: The format of the county data is slightly different than the other data files. To accomadate the 2 digit state code and the 3 digit county FIPS code, the first field contains 11 columns. The other data files still contain 10 columns. Element Record Name Position Element Description STATE-CODE 1-2 STATE-CODE as indicated in State Code Table as described in FILE 1. Range of values is 01-48. DIVISION-NUMBER 3-5 COUNTY FIPS - Range of values 001-999. ELEMENT CODE 6-7 01 = Precipitation 02 = Average Temperature 25 = Heating Degree Days 26 = Cooling Degree Days 27 = Maximum Temperature 28 = Minimum Temperature YEAR 8-11 This is the year of record. Range is 1895 to current year processed. (all data values are right justified): JAN-VALUE 12-18 Monthly Divisional Temperature format (f7.2) Range of values -50.00 to 140.00 degrees Fahrenheit. Decimals retain a position in the 7-character field. Missing values in the latest year are indicated by -99.99. Monthly Divisional Precipitation format (f7.2) Range of values 00.00 to 99.99. Decimal point retains a position in the 7-character field. Missing values in the latest year are indicated by -9.99. FEB-VALUE 19-25 MAR-VALUE 26-32 APR-VALUE 33-39 MAY-VALUE 40-46 JUNE-VALUE 47-53 JULY-VALUE 54-60 AUG-VALUE 61-67 SEPT-VALUE 68-74 OCT-VALUE 75-81 NOV-VALUE 82-88 DEC-VALUE 89-95