README FILE FOR NOAA'S 1981-2010 SUPPLEMENTAL CLIMATE NORMALS OUTLINE I. CONTENTS II. FILENAMING III. FILE FORMATS IV. UNITS V. SPECIAL VALUES VI. FLAGS I. CONTENTS readme-supp.txt - this file status-supp.txt - the status history of the 1981-2010 Supplemental Normals Below are descriptions of the four directories at this level. A. products directory The 1981-2010 Normals are located in the products directory. Within products, there are four subdirectories: 1. agricultural - contains all agricultural normals files including growing degree day normals, frost-freeze date probabilities, growing season length normals, and probabilities of frost-freeze occurrence. 2. air-freezing-index - contains the air freezing index return period file 3. hourly-10yr - contains all 2001-2010 normals derived from hourly data, including temperature, dew point temperature, heat index, wind chill, wind, cloudiness, heating and cooling degree hours, and pressure normals. 4. monthly-temperatures - (future directory) will contain monthly temperature normals of maximum, minimum, and average temperature computed using 5-, 10-, 15, and 20-year averages; OCN; and the Hinge Fit approach. B. station-inventories directory This directory contains station inventories for each product class. These inventories include the GHCN-Daily ID, latitude, longitude, state, and station names. 1. afi-inventory.txt contains all stations used in the air freezing index analysis 2. agri-inventory.txt contains all stations used in the agricultural normals analysis (except growing degree days, which has its own inventory below) 3. grdd-inventory.txt contains all stations used in the growing degree day analysis 4. hly-inventory.txt contains all stations used in the hourly analysis 5. temp-nnyear-inventory.txt (future file) will contain all stations used in the 5-, 10-, 15-, and 20-year monthly temperature normals analysis 6. temp-ocn-hinge-inventory.txt (future file) will contain all stations used in the OCN and Hinge Fit monthly temperature normals analysis C. documentation directory The documentation directory contains technical information about how the normals were computed and other relevant information. 1. afi-manuscript.pdf is a manuscript in review with the Journal of Applied Meteorology and Climatology that describes the Air Freezing Index return periods. 2. agricultural-normals-filenames.txt lists the filenames and descriptions of files containing the agricultural normals. 3. agricultural-normals-methodology.pdf is a manuscript that describes the methodology used to compute the agricultural normals. 4. hourly-10yr-filenames.txt lists the filenames and descriptions of files containing the 10-year normals derived from hourly data 5. hourly-methodology-addendum-2014.pdf describes the methodology utilized to compute all normals calculated from hourly data. 6. monthly-temperatures-filenames.txt (future file) will list the filenames and descriptions of files containing the supplemental monthly temperature normals. 7. monthly-temperatures-methodology.pdf (future file) will describe the methodology used to compute the supplemental monthly temperature normals. D. source-datasets directory The source-datasets directory contains source datasets used to compute the 1981-2010 Supplemental Normals found in this collection. 1. daily-filled-adjusted-tmax.dat.gz contains the serially-complete maximum temperature values used to compute seasonal Air Freezing Index values 2. daily-filled-adjusted-tmin.dat.gz contains the serially-complete minimum temperature values used to compute seasonal Air Freezing Index values 3. isdlite-normals.tar.gz contains the ISD-Lite hourly data 4. monthly-filled-tmax-1951-2010.txt (future file) will contain the serially-complete monthly maximum temperature values from 1951 to 2010 used to compute OCN and Hinge Fit Normals 5. monthly-filled-tmin-1951-2010.txt (future file) will contain the serially-complete monthly minimum temperature values from 1951 to 2010 used to compute OCN and Hinge Fit Normals The files listed above are intermediate values used in the computation of the Supplemental Normals. Users wishing to utilize these files for another purpose should contact NOAA/NCEI for formatting and other information. II. FILENAMING All supplemental normals files are named following the form RRR-EEEE-SSSSSS[-CCCCCCC].txt, where the portion in brackets is only used when necessary. The four components are defined as follows. A. RRR is the Reporting period, which can take the following values: ann = annual djf = December, January, February (winter) dly = daily jja = June, July, August (summer) mam = March, April, May (spring) mly = monthly rtp = return periods (used for Air Freezing Index) son = September, October, November (autumn) B. EEEE is the meteorological Element, which can take the following values: cldd = cooling degree days cldh = cooling degree hours clod = clouds dewp = dew point temperature grdd = growing degree days hidx = heat index htdd = heating degree days htdh = heating degree hours pres = sea level pressure tavg = daily mean temperature (average of tmax and tmin) temp = temperature tmax = daily maximum temperature tmin = daily minimum temperature wchl = wind chill wind = wind C. SSSSSS is the Statistic, which can take the following values: 05year = 2006-2010 average 10pctl = Climatological 10th percentile 10year = 2001-2010 average 15year = 1996-2010 average 1stdir = Prevailing Wind Direction 1stpct = Prevailing Wind Percentage 20year = 1991-2010 average 2nddir = Secondary Wind Direction 2ndpct = Secondary Wind Percentage 90pctl = Climatological 90th percentile afzndx = Air Freezing Index avgspd = Average Wind Speed baseNN = Growing degree day normals with base temperature NN NN can be 40, 45, 50, 55, 57, 60, 65, 70, or 72F hngfit = Hinge Fit Normals for 2010 normal = Climatological Average ocnorm = Optimal Climate Normals (OCN) pctbkn = Percent Broken (clouds) pctclm = Percent Calm (winds) pctclr = Percent Clear (clouds) pctfew = Percent Few (clouds) pctovc = Percent Overcast (clouds) pctsct = Percent Scattered (clouds) prbfst = Probability of first frost-freeze of the cold season occurring on specified date or earlier prbgsl = Probability of specified growing season length or longer prblst = Probability of last frost-freeze of the cold season occurring on specified date or later prbocc = Probability of occurrence of specified minimum temperature or lower tbXX86 = Truncated base growing degree day normal for corn XX can be 48 or 50F vctdir = Mean Wind Vector Direction vctspd = Mean Wind Vector Magnitude D. CCCCCCC is the Condition used in conjunction with probabilities: tXXFpYY = the XX temperature threshold at probability level YY% YY can be 10, 20, 30, 40, 50, 60, 70, 80,or 90 XX can be 16, 20, 24, 28, 32, or 36 lsthNNN = less than or equal to NNN whole degrees Fahrenheit NNN can be 016,020,024,028,032,036 III.FILE FORMATS A. FORMAT OF ANNUAL/SEASONAL FILES (ann-*.txt, djf-*.txt, mam-*.txt, jja-*.txt, son-*.txt) Each file contains the annual/seasonal values of one parameter at all qualifying stations. There is one record (line) per station. The variables in each record include the following: Variable Columns Type ---------------------------- STNID 1- 11 Character VALUE 19- 23 Integer FLAG 24- 24 Character ---------------------------- These variables have the following definitions: STNID is the GHCN-Daily station identification code. VALUE1 is the annual/seasonal value. FLAG1 is the completeness flag for the annual/seasonal value. See Flags section below. B. FORMAT OF MONTHLY FILES (mly-*.txt) Each file contains the values of one parameter for each month of the year at all qualifying stations. There is one record per station. The variables in each record include the following: Variable Columns Type ---------------------------- STNID 1- 11 Character VALUE1 19- 23 Integer FLAG1 24- 24 Character - - - - - - - - - - - - - - VALUE12 96-100 Integer FLAG12 101-101 Character ---------------------------- These variables have the following definitions: STNID is the GHCN-Daily station identification code. VALUE1 is the January value. FLAG1 is the completeness flag for January. See Flags section below. - - - - Value12 is the December value. Flag12 is the completeness flag for December. C. FORMAT OF DAILY FILES (dly-*.txt) Each file contains the values of one parameter for each day of the year at all qualifying stations. There is one record per station-calendar month. The variables in each record include the following: Variable Columns Type ---------------------------- STNID 1- 11 Character MONTH 13- 14 Integer VALUE1 19- 23 Integer FLAG1 24- 24 Character - - - - - - - - - - - - - - VALUE31 229-233 Integer FLAG31 234-234 Character ---------------------------- These variables have the following definitions: STNID is the GHCN-Daily station identification code. MONTH is the month in the 30-year period used. 01=January; 12=December VALUE1 is the value for the first day of the month. FLAG1 is a completeness flag based on the WMO normals classification, for the first day of the month. See Flags Section below. - - - - Value31 is the value for day 31 of the month. Flag31 is the completeness flag for day 31 of the month. D. FORMAT OF HOURLY FILES (hly-*.txt) Each file contains the values of one parameter for each hour of the day at all qualifying stations. There is one record per station-calendar day. The variables in each record include the following: Variable Columns Type ---------------------------- STNID 1- 11 Character MONTH 13- 14 Integer DAY 16- 17 Integer VALUE1 19- 23 Integer FLAG1 24- 24 Character - - - - - - - - - - - - - - VALUE24 180-184 Integer FLAG24 185-185 Character ---------------------------- These variables have the following definitions: STNID is the GHCN-Daily station identification code MONTH is the month in the 30-year period used. 01=January; 12=December DAY is the day in the 30-year period used. Varies from 1 to 31 in each record. VALUE1 is the value for the first hour of the day FLAG1 is a completeness flag based on the WMO normals classification, for the first hour of the day. See Flags Section below. - - - - VALUE24 is the value for last hour of the month. FLAG24 is the completeness flag for the last hour of the day E. FORMAT OF THE AFI RETURN PERIOD FILE (rtp-tavg-afzndx.txt) The file contains the AFI return period values for the following return periods (in years): 1.1, 1.25, 2, 2.5, 3.3, 5, 10, 20, 25, 50, 100. There is one record per station. The variables in each record include the following: Variable Columns Type ---------------------------- STNID 1 - 11 Character VALUE1 19 - 23 Integer FLAG1 24 - 24 Character - - - - - - - - - - - - - - VALUE11 89 - 93 Integer FLAG11 94 - 94 Character ---------------------------- These variables have the following definitions: STNID is the GHCN-Daily station identification code. VALUE1 is the 1.1-year return period. FLAG1 is a completeness flag. - - - - VALUE11 is the 100-year return period. FLAG24 is a completeness flag. F. FORMAT OF STATION INVENTORIES (*-inventory.txt) Each file contains on station per line. The variables in each record include the following: ------------------------------ Variable Columns Type ------------------------------ ID 1-11 Character LATITUDE 13-20 Real LONGITUDE 22-30 Real ELEVATION 32-37 Real STATE 39-40 Character NAME 42-71 Character GSNFLAG 73-75 Character HCNFLAG 77-79 Character WMOID 81-85 Character ------------------------------ These variables have the following definitions: ID is the station identification code. Note that the first two characters denote the FIPS country code, the third character is a network code that identifies the station numbering system used, and the remaining eight characters contain the actual station ID. LATITUDE is latitude of the station (in decimal degrees). LONGITUDE is the longitude of the station (in decimal degrees). ELEVATION is the elevation of the station (in meters, missing = -999.9). STATE is the U.S. postal code for the state (for U.S. stations only). NAME is the name of the station. GSNFLAG is a flag that indicates whether the station is part of the GCOS Surface Network (GSN). The flag is assigned by cross-referencing the number in the WMOID field with the official list of GSN stations. There are two possible values: Blank = non-GSN station or WMO Station number not available GSN = GSN station HCNFLAG is a flag that indicates whether the station is part of the U.S. Historical Climatology Network (HCN). There are two possible values: Blank = non-HCN station HCN = HCN station WMOID is the World Meteorological Organization (WMO) number for the station. If the station has no WMO number, then the field is blank. IV. UNITS tenths of degrees Fahrenheit for maximum, minimum, average, dew point, heat index, wind chill, and air temperature normals (e.g., "703" is 70.3F) whole degrees Fahrenheit for growing degree days dates (MM/DD) for probabilities of first/last events (e.g., 05/01 is May 1) whole days for growing season length tenths of percent for probabilities of occurrence (e.g., "299" is 29.9%) tenths of degree hours for heating and cooling degree hours (e.g., "152" is 15.2) tenths of millibars for mean sea level pressure normals (e.g., "10147" is 1014.7 mb) tenths of percent for prevailing and secondary wind direction percentages (e.g., "299" is 29.9%) prevailing and secondary wind directions can take on 8 values: 1=N, 2=NE, 3=E, 4=SE, 5=S, 6=SW, 7=W, 8=NW tenths of mph for wind speeds and vector magnitudes (e.g. "73" is 7.3 mph) whole degrees for mean vector wind directions V. SPECIAL VALUES -9999: missing or insufficient data; values cannot be computed -8888: date not defined (e.g. February 30, September 31) - used in daily files to achieve fixed-length records -7777: a non-zero growing degree day value that would round to zero -6666: parameter undefined; used in probabilities of first/last events to indicate the event is too infrequent to estimate dates, as well as AFI return periods that cannot be computed because too few years have non-zero seasonal AFI values; "too warm to compute" -4444: indicates year-round risk of frost-freeze; "too cold to compute" VI. FLAGS Flags accompany every Normals value and indicate the completeness of the data record used to compute each value. There are six flag options described generally below. C = complete (all 30 years used) S = standard (no more than 5 years missing and no more than 3 consecutive years missing among the sufficiently complete years) R = representative (observed record utilized incomplete, but value was scaled or based on filled values to be representative of the full period of record) P = provisional (at least 10 years used, but not sufficiently complete to be labeled as standard or representative). Q = quasi-normal (at least 2 years per month, but not sufficiently complete to be labeled as provisional or any other higher flag code). The associated value was computed using a pseudonormals approach or derived from monthly pseudonormals. Blank = the data value is reported as a special value such as -8888