How are cloud heights reported?
Clouds are always reported by weather stations in feet above ground level (AGL). Once you know the cloud heights in MSL, you can determine where you should fly, since altimeters are set in feet above MSL, not in feet AGL.
What is the cloud ceiling height?
Definitions. The height above the ground or water of the base of the lowest layer of cloud below 6000 meters (20,000 feet) covering more than half the sky.
How do I report a cloud in Metar?
Cloud amount is reported as FEW = few (1-2 oktas), SCT = scattered (3-4 oktas), BKN = broken (5-7 oktas) or OVC = overcast (8 oktas), followed by the height of the cloud base in hundreds of feet above aerodrome elevation e.g. SCT018 = scattered clouds at 1800 ft.
How do you find a cloud ceiling?
Here’s how to calculate a cloud base:
- Find the difference between the temperature at the surface and the dew point.
- Divide the difference between 2.5.
- Multiply the result by 1,000.
- This will then give you the height above ground level.
- Add the elevation of the airfield and this will give height above sea level.
Are clouds in a Metar MSL or AGL?
Remember, METAR and TAF report the height of clouds AGL, not MSL. OVC040 = Overcast at 4,000 ft above the airport.
What is VV in Metar?
Vertical visibility (VV) is reported in hundreds of feet. Partially obscured is reported as SKC ( if no cloud) or is included with the first layer.
How high is a cloud?
Clouds are generally encountered over a range of heights between the ground and about 60,000 feet….
| Level | High |
|---|---|
| Cloud | Cirrus Cirrocumulus Cirrostratus |
| Polar region | 10 000 – 25 000 ft |
| Temperate region | 16 500 – 45 000 ft |
| Tropical region | 20 000 – 60 000 ft |
Why do clouds stop at a certain height?
At a certain height, air cools enough for any water vapour to condense into droplets and form visible clouds. The droplets are liquid water, and therefore denser than air, but they are tiny, so they have a low terminal velocity and fall very slowly.
What is CIG in a Metar?
CIG (Ceiling=Lowest BKN/OVC layer or height of VV)
How is cloud top calculated?
Find the difference in temperatures from the surface to the cloud tops. The difference between -8 and -22 = -16 or 16 degrees. The normal lapse rate is 2 degrees C for every 1000 feet, so then we divide 16 by 2 and get 8 (thousand feet). 8000 feet above the surface is the top of the clouds.