That looks suspiciously like a plot generated by the WeeWX image generator, if that is the case the data is solely obtained from the archive and not the daily summaries. So whilst it is necessary to do some rebuilding of the daily summaries after correcting bad data in the archive, it will have no effect on WeeWX image generator generated plots.
What could possibly be the issue is that the WeeWX generated plots are re-generated at different intervals depending on the aggregation period of the underlying data used in the plot. For day plots this is every archive period, week plots every hour, month plots every 3 hours and year plots every 24 hours. rain plots are a little different in that day plots use a 1 hour aggregation period whereas week, month and year use a 24 hour aggregation period. So rain day plots are updated every 1 hour and week, month and year every 24 hours. If this is the issue it will come good in time once the offending plot is regenerated. Often the easiest thing to do is just delete all plots to force regeneration of all plots during the next report cycle.
Gary