Overcast vs Obscured

Overcast versus Obscured: What’s the difference?

Image of Obscured Sky vs Overcast Sky

In the GLOBE Clouds protocol and GLOBE Observer mobile app, members can report if the sky is “overcast” or “obscured”. But what is the difference? Below are some tips to help! All the photographs featured were collected by GLOBE observers.

Obscured and overcast can be confusing, but the below information will help clarify these terms. 

 

Definitions

Overcast: The sky is completely covered by clouds (cloud cover greater than 90%). This means that there is little or no blue sky. When it is overcast, the clouds are stratus clouds. Stratus are gray or grayish white.

Photos of Overcast Sky Conditions

 

Obscured: Something is blocking both the view of the sky and the clouds. This could be dust, haze (pollution), smoke, volcanic ash or even heavy rain or snow. Snow will appear white, but other obscurations may give the sky a brownish or orangish hue.

Images of Obscured Cloud COnditions

 

How to Take Photographs

Image of people with camera tilted taking image of sky
For overcast skies, tilt the camera at a 14-degree angle up at the sky. The GLOBE Observer app can help by automatically taking the photo when the device is titled at the right angle.

Image of camera taking photo straight ahead
For obscured skies, look straight ahead at the horizon, the same way as when making visibility reports. Those using the GLOBE Observer app should follow these steps to submit a photograph of the horizon. The example in these steps is for dust. Make sure to select the obscuration that was actually observed (for example, smoke or haze).

 

What If There Is a Mix?


An obscuration can be mixed with clouds. If the obscuration covers 30 percent or more of the view of the sky, then only report the obscuration observed. Use the steps above to take the photographs.

 

Helpful tips to make cloud observations.