Metar reports are very important for pilots and air traffic controllers as it gives them the most accurate weather information available to them. This information is critical to the safety of the flight, so it must be accurate and up-to-date.
Importance of Correct clouds Information In METAR:
Incorrect cloud information can be a serious problem for pilots. The incorrect cloud information may cause a pilot to make the wrong decisions when flying. Incorrect cloud information can lead to a lot of unnecessary troubles in the air. If you are going to fly to a place with bad weather conditions, it is important that you get the right information about the weather there. If pilots do not get the right information about the weather, they may land in dangerous situations. For example, if a pilot has a METAR report with a cloud at 2,000 feet and the METAR is issued by a ground observer, the pilot will know that there is a cloud at 2,000 feet. This information can be used to make an informed decision about smooth flight operations.
Reporting Clouds in METAR:
In METAR clouds are reported as FEW SCT, BKN, and OVC along with their height above the ground of the weather station of the airport. For example:
METAR LUDO 13007KT 3000 FU NSC 18/16 Q1011 TEMPO 3000
In the above example, there are no significant clouds reported. Clouds are reported in METAR as:
FEW: 1-2 Octas clouds
SCT: 3-4 Octas clouds.
BKN: 5-7 Octas Clouds.
OVC: 8 octas clouds(Sky is fully covered with clouds).
Cloud height in feet above the ground is reported along with cloud amount i.e if 2 octas clouds at 2500 feet then FEW025 is reported. Cloud heights are reported in ascending order.
After FEW there will be no other FEW reported except for convective clouds i.e CB and TCU.
FEW025 FEW0030 is wrong.
FEW025CB FEW0030 is correct.
clouds are reported in sequence wise of their heights.
First FEW clouds with lower heights are reported, then SCT then BKN, and then OVC.
FEW035 SCT100 OVC200 is correct
FEW040 OVC100 is correct
SCT100 FEW035 is wrong
Clouds layer 1-2 octas are reported first then the 3-4 octas layer than 5-7 octas layer and then the 8 octas layer according to ascending order of their heights from the ground level.
If visibility is 10 km or more and there are no clouds below 8000 ft then CAVOK (cloud and visibility ok) is reported instead of visibility and cloud group .i.e METAR LUDO 00000KT CAVOK 18/16 Q1011.
If there are no clouds below 8000 feet then NSC is reported in METAR. If there is no clouds below 8000 feet and visibility is 10 km or more then CAVOK is reported.
In conclusion, METAR reports are very important for aviation. In addition to giving pilots and air traffic controllers an idea of what to expect in the weather, they also serve as a primary source of weather information for pilots.