Preliminary Climate Data (F6) Codes Explained

Column Number

Abbreviation
Explanation
1
Dy
The date.
2
Max
The highest temperature for the day.
3
Min
The lowest temperature for the day.
4
Avg
The average temperature for the date. Computed by finding the average of the values in columns 2 and 3, then rounding up (if necessary).
5
Dep
Departure from normal. The difference between column 4 and the 30 year normal temperature for this date.
6a
Hdd
Heating degree days. Computed by subtracting the average temperature from 65. If less than 0, HDD=0.
6b
Cdd
Cooling degree days. Computed by subtracting 65 from the average temperature. If less than 0, CDD=0.
7
Wtr
Total precipitation for the day in inches. This includes all forms of precipitation, melted if snow or ice occurred.
8
Snw
Total snowfall for the day in inches.
9
Dpth
Snow depth in inches at 6am CST in inches.
10
Avg Spd
Average wind speed for the day in mph.
11
Mx Spd
The highest wind speed measured over a 2 minute period in mph.
12
2 Min Dir
The direction (in compass degrees divided by 10) from which the wind speed in column 11 came from. ( N=36 S=18 W=27 E=09 etc.)
13
Min
The number of minutes of sunshine received at the station.
14
Psbl
The percentage of possible sunshine. Computed by dividing the minutes of sunshine (column 13) into the total possible minutes.
15
S-S
The average sky cover between sunrise and sunset in tenths.
16
Wx

Weather types observed during the day. Use the following list to decode types:
1=Fog or mist.
2=Dense fog (visibility is reduced to 1/4 mile or less).
3=Thunder.
4=Ice pellets (sleet).
5=Hail.
6=Glaze or rime (freezing rain).
7=Dust storm or sandstorm (visibility reduced to 1/4 mile or less).
8=Smoke or Haze.
9=Blowing snow.
X=Tornado.

17
Wnd Spd
Peak wind speed for the day in mph. The highest wind speed observed at the station.
18
Wnd Dr
The compass direction from which the peak wind speed came.

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.