What's the Climate in Charleston, SC?

Image is from https://www.usclimatedata.com/climate/charleston-afb/south-carolina/united-states/ussc0052

Why would this be a climate graph rather than a weather graph?

In which month is there the most precipitation in Charleston, SC?

In which month is there the least precipitation in Charleston, SC?

How does the amount of rainfall change from winter to spring to fall?

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