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In terms of precipitation, rainfall in Kolkata ranges from 0.3 - 14.0 inches per month. August is typically the wettest month, when rainfall can reach 14.0 in. December is typically the driest time to visit Kolkata when rainfall is around 0.3 in.
If weather is an important factor for your trip to Kolkata, use this chart to help with planning. For those seeking warmer temperatures, April is the ideal time of year to visit, when temperatures reach an average of 87.8 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 68.0 F).