FIELD numbers are shown with column positions in parenthesis.

FIELD 1 (1-6): COOPERATIVE STATION NUMBER
This 6-character alphanumeric station identifier is assigned by the National Climatic Data Center.
The first two digits refer to a state code (value range is 01-91; reference Table "A"). The next four digits
refer to the Cooperative Network Index number (value range is 0001-9999). Missing/not assigned = 999999.

FIELD 2 (8-12): WBAN STATION NUMBER
This 5-character alphanumeric station identifier is assigned by the National Climatic Data Center.
It originally referred to Weather Bureau, Army, and Navy (WBAN) stations which mailed weather observational forms to NCDC.
These stations normally have more detailed data available than strictly cooperative stations, so stations with WBAN numbers
will usually have additional data elements.

Optional FIELD (14 - 43): STATION NAME
This 30-character alphanumberic FIELD is displayed if the data selection is for data with Station Name. Spacing for all FIELDs following are adjusted 31 characters (e.g., Division Number = 45-46).

FIELD 3 (14-15): DIVISION NUMBER
These two digits refer to the Cooperative Network Division Number (value range is 01-10; 99 = missing Division Number; reference Table "B").

FIELD 4 (17-20): ELEMENT TYPE
The type of data element stored in this record. Range is listed below. (Metric units were used by most of the Caribbean countries except Puerto Rico and the Virgin Islands.)

CLDD - Monthly cooling degree days - base 65 deg. F. (1980 onward.)
DP01 - Number days with greater than or equal to 0.1 inch precipitation. (1954 onward.)
DP03 - Number days with greater than or equal to 3.0 millimeters precipitation. (Metric stations only.)
DP05 - Number days with greater than or equal to 0.5 inch precipitation. (1951 onward.)
DPOH - Number days with greater than or equal to 0.01 inch precipitation. (Only before 1954.)
DPOQ - Number days with greater than or equal to 0.25 inch precipitation. (Only before 1951.)
DP10 - Number days with greater than or equal to 1.0 inch precipitation.
DP25 - Number days with greater than or equal to 25.0 millimeters precipitation. (Metric stations only.)
DP50 - Number days with less than or equal to 50.0 millimeters precipitation. (Metric stations only.)
DPNP - Departure from normal monthly precipitation.
DPNT - Departure from normal monthly temperature.
DSNW - Number days with snow depth greater than or equal to 1 inch.
DT00 - Number days with minimum temperature less than or equal to 0 deg. F.
DT15 - Number days with maximum temperature less than or equal to 15 deg. C. (Metric stations only.)
DT30 - Number days with maximum temperature greater than or equal to 30 deg. C. (Metric stations only.)
DT32 - Number days with minimum temperature less than or equal to 32 deg. F.
DT60 - Number days with minimum temperature less than or equal to 59 deg. F. (Puerto Rico and Virgin Islands only.)
DT70 - Number days with maximum temperature greater than or equal to 70 deg. F. (Alaska only.)
DT90 - Number days with maximum temperature greater than or equal to 90 deg. F.
DX15 - Number days with maximum temperature less than or equal to 15 deg. C. (Metric stations only.)
DX32 - Number days with maximum temperature less than or equal to 32 deg. F.
DX60 - Number days with maximum temperature less than or equal to 59 deg. F. (Puerto Rico and Virgin Islands only.)
EMXP - Extreme maximum daily precipitation in the month. (Contains the day of occurrence in the DAY FIELD.)
EMNT - Extreme minimum temperature for the month. (Contains the day of occurrence in the DAY FIELD.)
EMXT - Extreme maximum temperature for the month. (Contains the day of occurrence in the DAY FIELD.)
FRZD - Freeze Data

Freeze data contains the dates of the last spring (01 January through 30 June) and the first fall occurrences (01 July through 31 December) for five thresholds of temperature (16, 20, 24, 28, and 32 deg. F). The MONTH and DAY FIELDs contain the date of occurrence. The DATA-VALUE FIELD contains the sign and actual temperature.

Example: The first threshold position that represents the last occurrence of a temperature less than or equal to 16 deg. F in the spring will appear as 020700016 (February 7th, temperature was 16 deg. F.) (Reference Table C)

HTDD Monthly heating degree days - base 65 deg. F. (July 1950 onward.)
MMNP Monthly mean minimum temperature of evaporation pan water.
MMNT Monthly mean minimum temperature.
MMXP Monthly mean maximum temperature of evaporation pan water.
MMXT Monthly mean maximum temperature.
MNTM Monthly mean temperature.
MXSD Maximum snow depth during the month. (Contains the day of occurrence in the DAY FIELD.)
TEVP Total monthly evaporation.
TPCP Total monthly precipitation.
TSNW Total monthly snowfall.
TWND Total monthly wind movement (in miles) over evaporation pan.

SOIL DATA
Soil records are from 1982 forward. The last two digits on soil element names represent codes for soil cover and soil depth. Example: "MN11" represents the element name for mean monthly soil temperature of grass cover at 2 inches and/or 5 cm. There is no distinction whether the depth reading is read in inches or centimeters. See "Known Uncorrected Problems" section before using soil records.

When using soil data you must examine the FLAG-1 and FLAG-2 FIELDs. FLAG-1 FIELD contains flags to determine if temperature at observation time was taken in the morning or the evening (AM or PM). FLAG-2 FIELD determines if the observation taken is a subplot within the primary plot.

MNyz Monthly mean minimum soil temperature.
HNyz Highest minimum soil temperature for the month.
LNyz Lowest minimum soil temperature for the month.
MOyz Monthly mean soil temperature at observation time.
HOyz Highest soil temperature at observation time.
LOyz Lowest soil temperature at observation time.
MXyz Monthly mean maximum soil temperature.
HXyz Highest maximum soil temperature for the month.
LXyz Lowest maximum soil temperature for the month.

CODE (y = Code for soil cover)(z = Code for soil depth)(Reference TABLE D.)

FIELD 5 (22-23): ELEMENT UNIT
The units and decimal position of the data value for this record. (Reference TABLE E - Range of values.)

FIELD 6 (25-28): YEAR
This is the year of record. Range = 1831-present.

FIELD 7 (30-30): AM-PM
(Soil temperatures only.) Indicator used to determine if the soil temperature at observation time was taken in the morning or the evening. (Reference TABLE F.)

FIELD 8 (32-32): SUB-PLOT
(Soil temperatures only.) Indicator used to determine if the observation is for a primary plot or a plot within a primary plot (subplot) (Reference TABLE G).

FIELD 9 (34-35): MONTH
Month of element value. Range = 1-13. 13 => annual value.

FIELD 10 (37-38): DAY
Day of element value, if applicable. Range = 00-31. 00 => elements are monthly means or number of days of occurrences of precipitation and/or temperatures within specified limits as listed in the ELEMENT TYPE FIELD.

FIELD 11 (40-45): DATA-VALUE
Actual data value. The first position of this FIELD is the "sign" of the meteorological data value. This position contains either a blank or a minus sign (never a plus sign). The remaining positions of this FIELD contain a five-digit integer. Units and decimal position are indicated by the ELEMENT UNITS FIELD.

FIELD 12 (47-47): FLAG-1
Data Measurement Flag.

A - Accumulated amount. This value is a total that may include data from a previous month or months (TPCP).

B - Adjusted Total. Monthly value totals based on proportional available data across the entire month. (CLDD, HTDD, TEVP, TWND)

E - An estimated monthly or annual total.

I - Monthly means or totals based on incomplete time series. 1 to 9 days are missing. (DSNW, MMNT, MMXP, MMXT, MNTM, TPCP, TSNW) M "M" is used to indicate data element missing.

S - Precipitation for the amount is continuing to be accumulated. Total will be included in a subsequent value (TPCP).

Example: Days 1-20 had 1.35 inches of precipitation, then a period of accumulation began. The element TPCP would then be 00135S and the total accumulated amount value appears in a subsequent monthly value.

If TPCP = "99999" there was no precipitation measured during the month. Flag 1 is set to "S" and the total accumulated amount appears in a subsequent monthly value.

T Trace of precipitation, snowfall, or snowdepth.

The precipitation data value will = "00000".

(EMXP, MXSD, TPCP, TSNW)

+ The phenomena in question occurred on several days. The date in the DAY FIELD is the last day of occurrence.

(blank) No report when data value = "99999".

Data Quality FLAG. FLAG-2 is only used if FLAG-1 contains "T". Freeze data is the only exception.

A - Accumulated amount.
E - Estimated value.
+  - Value occurred on more than 1 day - last date of occurrence is used.

NOTE:  FIELDS 9-13 are then repeated for each month of the year, beginning with 01 in the MONTH FIELD, and ending with 13 in the MONTH FIELD. So, the data for MONTH 02 will occupy columns 51-66, MONTH 03 = 68-83, etc.

Known Uncorrected Problems:  There are sporadic instances of duplicate data records, in which an element (e.g., TPCP) for a year has two data records instead of one. In these cases, one of the data records will contain mostly missing values, while the 2nd data record will have the remainder of the data. You can combine the 2 records to obtain the most complete data for the affected year. The historical data were converted from existing digital files and structured into the element structure format. These data were processed through a gross value check and not the current edit system. It is NCDC's goal to bring these historical files up to the same level of quality as those from 1982 onward as resources become available. Soil data were added in January 1982 with approximately 250 stations reporting soil data. Soil data before 1982 are available in TD9639. In January 1987, the 1982 and 1983 soil data were removed due to poor data quality. There may be a few cases in which precipitation and temperature are in metric units but are not labeled as such in the "Element Units" FIELD. This seems to be limited to data from the early 1960's from the U.S. Virgin Islands and Puerto Rico.

Table C. FREEZE DATA TABLE
Threshold Meaning Position
1 Temp less than or equal to 16 deg. F Last occurrence in the
2 Temp less than or equal to 20 deg. F spring.
3 Temp less than or equal to 24 deg. F
4 Temp less than or equal to 28 deg. F
5 Temp less than or equal to 32 deg. F
6 Temp less than or equal to 16 deg. F First occurrence in the
7 Temp less than or equal to 20 deg. F fall.
8 Temp less than or equal to 24 deg. F
9 Temp less than or equal to 28 deg. F
10 Temp less than or equal to 32 deg. F

For no occurrences: MONTH = 99
DAY = 99
DATA-VALUE = -99999
FLAG-1 = M
FLAG-2 = +