Unfortunately it does seem that the rogue 0.44" of precipitation has made it's way into your data on 8/16/17 at 4:54AM and again at 12:20PM. Alas there is a known issue with the data coming from the wunderground via their public API endpoint which was used by wufyi so far.
The good news is that we are testing a working solution, which has proven to be much more accurate, over at beta.wufyi.com and it will soon make it's way over to the general wufyi.com implementation.
If you wish to make use of a better data interface before it is available to a general public, just edit your cron-job URL from starting with "wufyi.com?..." to start instead with "beta.wufyi.com?..." (where ... are your custom parameters) and you should automatically start getting a cleaner data source, otherwise your URL will start fetching from improved data source early next week after the testing is complete.