Training Guide in Surface Weather Observations - Multiple Choices

CHAPTER 9
REVIEW EXERCISES
OBSERVING and CODING EXERCISES
Complete each practice observation. First, fill in the blanks for each layer of sky cover, and visibility
when required. Use the dew point table provided in Appendix B to compute the dew point temperature;
also use the temperature conversion charts provided in Chapter 6. The dew point table is required for
these exercises even though many stations use the psychrometric calculator (see Chapter 6). Then code
the report as it would be transmitted in a METAR/SPECI on the line below. Not all stations are required
to report each element; for example, a SAWRS will generally not report the dew point temperature in
the body, or the sea-level pressure and hourly temperatures in remarks. All observations are taken on
the 21st of March 1997 at Alexandria, LA. The first exercise has been completed.
Exercise #1 - Example:
Lower layer has 3 /8ths coverage. Prevailing visibility is 4 statute miles.
Upper layer has 4 /8ths coverage. Sector visibility and direction (if any).
Total sky coverage is 7 /8ths.
Given:
Altimeter: 29.933 inches
Sea-level pressure: 999.7 hPa
Wind indicator has direction of 230°, speed is 10 knots.
Dry bulb temperature is 68.6°F; wet bulb temperature is 58.1°F
Computed dew point is 50°F
Haze is obstructing the visibility.
The last element was observed at 1055 UTC.
METAR KAEX 211055Z 23010KT 4SM HZ SCT070 BKN120 20/10 A2993 RMK SLP997
T02030100
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