That is caused by the problems at WU
The same URL is used in all versions
https://www.wunderground.com/weatherstation/WXDailyHistory.asp?ID=KPARENFR7&graphspan=year&year&format=1
In the 0620 version it returned no-data, only the header line. Other times it will return data.
File: ./chartswudata/KPARENFR7Y.txt Filetime (UTC): 2019-06-27T05:21:25+00:00 which an age of 5 hrs 16 min 58 seconds
The file will remain in cache for 12 hours. If you delete the file, the next run of station-cron or the next visit to your site will try to load the file again.
You can chack how old the files are with: https://beacon-rd.000webhostapp.com/pws07beta0620/w34_load_files.php?test
Nobody knows if and when the retrieval from WU will work correctly, and for how long.
There are numerous discussions about this on the WX forum as a lot of other scripts also suffer from it
I decided to wait until it is clear if we can access our historical data and how. For now even the API to retrieve the data is inconsistent.
Wim