Assuming the data is in the database (not a safe assumption), just delete
the charts. They will get regenerated at the next reporting cycle.
If they still have holes, then there must be data missing in the database.
You can search for the holes with commands something like:
*sqlite3
Last tuesday there was a power outage at my house and ever since there is a
hole in the charts of the Season skin.Whily there was the outage the
program was obviously not running but weewx did catuch up the data for that
time when power came back. What is the best way to regenerate the charts ?