FAA Part 107 Remote Pilot (UAG)OperationsMedium
A remote pilot reviews the following TAF excerpt before a planned evening survey flight: 'KXYZ 151720Z 1518/1624 24012G20KT P6SM SCT040 FM160300 28008KT 4SM BR OVC008.' According to this forecast, what conditions are expected beginning at 0300Z?
- A6 statute miles visibility with an overcast ceiling at 8,000 feet
- B4 statute miles visibility with a broken ceiling at 8,000 feet
- C6+ statute miles visibility with scattered clouds at 4,000 feet
- D4 statute miles visibility with mist and an overcast ceiling at 800 feet
Show answer & explanationAnswer & explanation
Correct answer: D. 4 statute miles visibility with mist and an overcast ceiling at 800 feet
The 'FM160300' group starts a new forecast period at 0300Z with 4SM visibility, BR (mist), and OVC008, meaning an overcast ceiling at 800 feet AGL. The three-digit cloud height code is read in hundreds of feet, so 008 = 800 feet.
Why the other options are wrong
- A. Misreads both the visibility figure and the ceiling altitude.
- B. Misreads the ceiling type (overcast, not broken) and the altitude by a factor of 10.
- C. This describes the earlier period before the FM group, not the new forecast.
TAF Interpretation
Terminal Aerodrome Forecasts predict weather at an airport for up to 30 hours, with 'FM' groups marking a complete change in conditions at a specified time.
- Cloud height coded in hundreds of feet (e.g., 008=800ft)
- FM group = rapid, significant change
- BR = mist, a visibility-reducing phenomenon
Memory trick: FM = 'From this Moment' the weather changes.