RPC Aviation Weather Services 2 — Questions and Answers
Question 1: A METAR observation includes the remark 'TS ALQDS.' What does this indicate?
- Thunderstorms in all quadrants around the station (Correct answer)
- Towering cumulus clouds in all quadrant directions
- Temperature sensors are active in all quadrants
- Turbulence at all altitudes around the quadrant
Correct answer: Thunderstorms in all quadrants around the station
'TS ALQDS' in a METAR remark means thunderstorms are reported in all quadrants surrounding the reporting station.
Question 2: Which aviation weather product provides forecasts for specific airport terminal areas and is valid for 24 to 30 hours?
- METAR
- TAF (Correct answer)
- SIGMET
- AIRMET
Correct answer: TAF
A Terminal Aerodrome Forecast (TAF) provides weather forecasts for a 5 statute mile radius around an airport and is valid for 24 to 30 hours.
Question 3: When decoding a winds aloft forecast, the entry '9900' for wind direction and speed means:
- Winds are calm or less than 5 knots (Correct answer)
- Wind speed exceeds 99 knots
- Wind direction is 990 degrees magnetic
- Data is unavailable for that altitude
Correct answer: Winds are calm or less than 5 knots
'9900' in a winds aloft forecast is a special code indicating light and variable winds (calm or less than 5 knots).
Question 4: A SIGMET (WS) is issued for which of the following conditions?
- Moderate icing below 18,000 feet MSL
- Moderate turbulence below 18,000 feet MSL
- Severe or extreme turbulence at any altitude (Correct answer)
- Marginal VFR conditions at airport terminals
Correct answer: Severe or extreme turbulence at any altitude
SIGMETs are issued for hazardous meteorological conditions significant to all aircraft, including severe or extreme turbulence, regardless of altitude.
Question 5: On a surface analysis chart, isobars spaced closely together indicate:
- Light and variable winds
- Strong pressure gradient and stronger winds (Correct answer)
- High relative humidity in the area
- Stable air with little vertical mixing
Correct answer: Strong pressure gradient and stronger winds
Closely spaced isobars represent a steep pressure gradient, which produces stronger winds between the high and low pressure areas.
Question 6: What does the 'SM' unit represent in a METAR visibility report?
- Statute miles (Correct answer)
- Sea miles
- Standard meters
- Sight miles
Correct answer: Statute miles
In a METAR, 'SM' denotes statute miles, the standard unit used for reporting visibility in U.S. aviation weather reports.
Question 7: A remote pilot notices the surface temperature is 85°F and the dewpoint is 83°F. This small temperature-dewpoint spread suggests:
- Very low relative humidity and excellent visibility
- High relative humidity and increased likelihood of fog or low clouds (Correct answer)
- Rapidly decreasing pressure gradient
- Unstable air with severe turbulence potential
Correct answer: High relative humidity and increased likelihood of fog or low clouds
A small temperature-dewpoint spread indicates the air is near saturation, increasing the likelihood of fog, mist, or low cloud formation.
RPC Aviation Weather Services 2
A METAR observation includes the remark 'TS ALQDS.' What does this indicate?