Cloud API Parameters

Amount of Cloud Cover | Interval Values of Cloud Cover| Mean Amount of Cloud Cover over the Last 10 Years | Ceiling Height | Cloud Base | Convective Cloud Top Height | Cloud Top Temperature | Probability for Contrails

Amount of Cloud Cover

Gives the amount of cloud cover in percent or octas.

<level>_cloud_cover:<unit>

Available levels: low, medium, high, total, effective

Available units: octas, p

Note: A value of -666 denotes that there are no clouds present.

low cloud cover corresponds approximately to levels between 0 and 1800m above ground level.

medium cloud cover corresponds approximately to levels between 1800m and 6300m above ground level.

high cloud cover corresponds approximately to levels higher than 6300m above ground level.

total cloud cover is the fraction of the sky covered by cloud at any height. Due to overlapping clouds at different heights, it may not correspond to the sum of the low, medium and high cloud covers.

effective cloud cover is a weighted sum of the low, medium and high level cloud covers relevant for solar energy forecasts. The low and medium level clouds have a higher weight than the high level clouds as the low and medium level clouds block more radiation.

Examples

  • Generate a csv file containing the amount of cloud cover in octas for every grid point of the specified area.

    https://api.meteomatics.com/2024-12-03T12:00:00Z/effective_cloud_cover:octas/50,5_35,20:1,1/csv

    validdate;2017-08-03 12:00:00
    parameter;effective_cloud_cover:octas
    data;5;6;7;8;9;10;11;12;13;14;15;16;17;18;19;20
    50;1;8;4;5;4;8;8;8;8;8;8;8;5;1;0;0
    49;7;5;6;4;8;5;2;4;4;3;8;0;6;0;0;0
    48;3;5;6;6;1;2;5;2;4;1;1;0;1;0;0;0
    47;2;5;3;4;1;0;2;0;1;1;0;0;0;0;0;0
    46;0;0;0;3;0;0;0;0;0;0;0;0;0;0;0;0
    45;0;0;0;0;0;0;0;0;0;0;0;0;0;0;0;0
    44;0;0;3;0;0;0;0;0;0;0;0;0;0;0;0;2
    43;0;1;0;0;0;0;0;0;1;0;0;0;0;0;2;1
    42;0;1;1;0;0;0;0;0;0;0;0;0;0;0;0;6
    41;0;4;1;0;0;0;0;0;0;0;0;0;0;0;1;1
    40;0;0;0;0;0;0;0;0;0;0;0;0;0;0;1;0
    39;0;0;0;0;0;0;0;0;0;0;0;2;0;0;1;0
    38;2;0;0;0;0;0;0;0;0;0;0;0;0;0;4;0
    37;0;0;0;0;0;0;0;0;0;0;0;0;0;0;0;0
    36;0;0;0;0;0;0;0;6;0;0;0;0;0;0;0;0
    35;0;0;0;0;0;0;0;0;0;0;0;0;0;0;0;0
  • Chart showing total cloud cover created in MetX: Cloud cover metx

Interval Values of Cloud Cover

Gives the mean cloud cover over the indicated duration.

<level>_cloud_cover_<measure>_<interval>:<unit>

Available levels: low, medium, high, effective, total

Available measures: mean

Available intervals: 1h, 2h, 6h, 12h, 24h

Available units: octas, p

Example:

Mean Amount of Cloud Cover over the Last 10 Years

Gives the mean amount of cloud cover over the last 10 years on a certain date at a specific location.

<level>_cloud_cover_10y_mean:p

Available levels: low, medium, high, total

low cloud cover corresponds approximately to levels between 0 and 1800m above ground level.

medium cloud cover corresponds approximately to levels between 1800m and 6300m above ground level.

high cloud cover corresponds approximately to levels higher than 6300m above ground level.

total cloud cover is the fraction of the sky covered by cloud at any height. Due to overlapping clouds at different heights, it may not correspond to the sum of the low, medium and high cloud covers.

Examples:

Ceiling Height

The ceiling height above ground level is an important parameter in aviation and is defined as the height of the lowest cloud layer covering more than half of the sky or where clouds are present above 6000m. The ceiling height is also available as a mean, maximum or minimum value over a specified time interval.

ceiling_height_agl:<unit>
ceiling_height_agl_<measure>_<interval>:<unit>

Units: m, ft

Measures: max, mean, min

Intervals: 1h, 2h, 3h, 6h, 12h, 24h, 48h

Note: A value of -666 denotes that there are no clouds present and hence no ceiling height or cloud base can be determined. If a value of -666 occurs during the specified time interval, this value is disregarded and is not taken into account when determining the chosen statistical measure.

Examples

Cloud Base

The cloud base above ground level gives the lowest altitude of the visible portion of a cloud.

cloud_base_agl:<unit>
cloud_base_agl_<measure>_<interval>:<unit>

Units: m, ft

Measures: max, mean, min

Intervals: 1h, 2h, 3h, 6h, 12h, 24h, 48h

Note: A value of -666 denotes that there are no clouds present and hence no ceiling height or cloud base can be determined. If a value of -666 occurs during the specified time interval, this value is disregarded and is not taken into account when determining the chosen statistical measure.

Examples

Convective Cloud Top Height

This parameter gives the height of convective cloud tops in metres above ground level. A value is only returned if convective clouds are likely to be present. Where no convective clouds are present, a value of -666 is returned.

convective_cloud_top_height_agl:<unit>
convective_cloud_top_height_agl_<measure>_<interval>:<unit>

Units: m

Measures: max, mean, min

Intervals: 1h, 2h, 3h, 6h, 12h, 24h, 48h

Note: If a value of -666 occurs during the specified time interval, this value is disregarded and is not taken into account when determining the chosen statistical measure.

Example:

Cloud Top Temperature

This parameter gives the temperature at the top of the highest cloud level. Where no clouds are present, a value of -666 is returned.

t_cloud_top:<unit>

Units: C, F, K

Example:

Probability for Contrails

This parameter gives the probability for contrails (artificial cirrus clouds produced by airplanes) on a specific level. It depends on the formation probability, that is based on the critical air temperature and on the persistance probability, that is based on the relative humidity over ice.

contrail_<level>:p

Available altitude levels: 2m to 20'000m (continuously), 5ft - 65600ft (continuously)

Available pressure levels: 1000hPa, 950hPa, 925hPa, 900hPa, 850hPa, 800hPa, 700hPa, 600hPa, 500hPa, 400hPa, 300hPa, 250hPa, 200hPa, 150hPa, 100hPa, 70hPa

Available flight levels: FL10 - FL600 (continuously)

Example:

Example:

  • Probability of contrails for Europe at a pressure level of 300hPa in MetX: Contrail probability 300h Pa