A pilot receives a TAF for their destination that includes the group 'TEMPO 1806/1809 3SM -SHRA BKN015'. How should the pilot interpret this forecast?
- ABetween 0600Z and 0900Z on the 18th, there will be a temporary improvement to 3 statute miles visibility with broken clouds at 1,500 feet.
- BBetween 0600Z and 0900Z on the 18th, there will be temporary periods of 3 statute miles visibility, light rain showers, and broken clouds at 1,500 feet.
- CThe forecast is temporarily amended for 18 hours, with 3 statute miles visibility, light rain showers, and broken clouds at 1,500 feet, beginning at 0600Z.
- DFrom 1800Z on the 6th until 0900Z on the 18th, the visibility will temporarily be 3 statute miles with light rain showers and broken clouds at 1,500 feet.
Show answer & explanationAnswer & explanation
Correct answer: B. Between 0600Z and 0900Z on the 18th, there will be temporary periods of 3 statute miles visibility, light rain showers, and broken clouds at 1,500 feet.
The 'TEMPO' group indicates that the specified weather conditions are expected to occur for less than one hour at a time, and for less than half of the forecast period, within the specified timeframe. '1806/1809' indicates the 18th day, from 0600Z to 0900Z. '3SM' is 3 statute miles visibility, '-SHRA' is light rain showers, and 'BKN015' is broken clouds at 1,500 feet AGL.
Why the other options are wrong
- A. TEMPO indicates conditions will temporarily prevail, not necessarily an improvement. '-SHRA' is light rain showers, not an improvement.
- C. TEMPO is a forecast condition, not an amendment. The duration '1806/1809' is a 3-hour period, not 18 hours.
- D. The date/time group '1806/1809' indicates a period on the 18th day, not from the 6th to the 18th.
TAF TEMPO Group
The 'TEMPO' group in a TAF indicates temporary fluctuations in forecast weather conditions that are expected to last for less than one hour at a time and cover less than half of the specified period.
- Indicates temporary changes.
- Conditions expected for less than 1 hour each occurrence.
- Total duration of temporary conditions covers less than 50% of the period.
- Used for visibility, weather, and sky conditions.
Memory trick: TAF groups: 'FM' is From, 'BECMG' is Becoming, 'TEMPO' is Temporary, 'PROB' is Probability.