It is better to underestimate.
Work Step by Step
Since its a natural disaster, in this case an underestimate is good. With underestimated data, people can take precautions beforehand, as they have enough time.
You can help us out by revising, improving and updating this answer.Update this answer
After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.