Average cloud cover by month
How cloudy each part of the world is on average in each month, from 2008–2017 satellite records. Dark blue is mostly clear, white is mostly overcast. These are long-term averages, not a forecast. Tonight’s forecast is on the tonight page. Tonight
Average cloud cover at New York
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Values are averages over a 2-degree grid cell (about 220 km north to south), so local effects such as mountains and coasts are smoothed out.
Data: NOAA NCEI, International Satellite Cloud Climatology Project (ISCCP-H), monthly means 2008–2017. Coastlines: Natural Earth. NOAA NCEI · Data sources
How to use this page
Choose a month to see how cloudy the sky usually is around the world, from long-term satellite records. Pick your place to read the average cloud cover there.
Frequently asked questions
Is this a weather forecast?
No. The maps show the average cloud cover for each month over many years, to help plan trips and choose a season. For tonight, use a weather forecast.
Where do the data come from?
From NOAA’s ISCCP-H satellite cloud climatology, which combines weather satellites from around the world.
Why is my area always cloudy in one month?
Many places have a cloudy season, such as a monsoon or a winter fog season. The maps show these patterns so you can plan around them.
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