Page 31 - AFMAN 15-111, 12 MAR 2019

AFMAN15-111 12 MARCH 2019 31

6.7.6. Colum 46 - Snow Depth is a measurement of the depth of the accumulated freezing and
solid precipitation that is on the surface at the time of the observation and is reported to the
nearest whole inch; encode amounts less than 0.5in as a trace.
6.7.6.1. Melted Precipitation Reporting Procedure. If solid precipitation melted during the
period, annotate the measurement as estimated and enter the estimated maximum depth
and the approximate time UTC of occurrence in column 90 (e.g. “E-MAX SNOW DEPTH
1 AT 1530”).

6.7.6.2. If the measured depth consists entirely of hail, prefix the entry with an “*” and
enter “*HAIL IN COL 46 AT 0350” in column 90.

6.8. Summary of the Day (SOD). The JET 3813 automatically populates some of the SOD data;
however, as part of the quality control program, weather personnel are responsible for entering
and/or correcting the data as needed. Note: JET has access to, and may record higher resolution
data than what is normally available to the end user (e.g. slightly higher maximum temperature or
wind speed that occurred between displayed measurements). With the exception of Column 70,
the information entered in the SOD fields consists of data collected during the 24 hour period
ending at midnight LST. See Figure 6.1 for examples and entry format.

6.8.1. Columns 66 and 67 - 24 Hour Maximum and Minimum Temperatures. Encode the
maximum and minimum temperatures in whole degrees Celsius.
6.8.2. Columns 68 and 69 - 24 Hour Precipitation and Snowfall. Enter the total amounts from
Columns 44 and 45 respectively. Exception: Stations taking midnight LST observations do
not include the value from their first 6-hourly observation when totaling amounts.
6.8.2.1. Prefix estimated amounts with an “E” and enter a remark in Column 90. Enter 0
if the phenomenon did not occur during the period.
6.8.2.2. If the entries are entirely trace amounts, encode the sum as a trace. Otherwise,
when computing the total, trace entries are considered 0 (i.e. synoptic observation
measurements of 0.0, 0.1, T, and 0.1 would total 0.2). Exception: Stations equipped with
a recording/totaling gauge report the recorded/total amount regardless.

6.8.3. Column 70 - Snow Depth. Enter the depth of solid precipitation on the ground at 1200
UTC; this entry is the same as that in Column 46 for the 1200Z observation. If personnel are
not on duty at 1200 UTC, enter depth as measured as near to 1200 UTC as practical along with
a remark in column 90 to indicate the time of observation (e.g., COL 70 ENTRY OBSVD AT
1330); no remark is needed for a “0” entry. If the precipitation consists entirely of hail, prefix
the entry with an “*” and annotate in Column 90 with “*HAIL IN COL 70 AT 1150.”

6.8.4. Columns 71, 72, and 73 - Peak wind data. Enter the maximum instantaneous speed and
associated direction observed during the period and time of occurrence to the nearest minute.
Note: This speed may be reported from an inactive sensor.