fluent-plugin-weather is a fluent plugin to copy output with adding weather field. Without ‘latitude’ and ‘longitude’ fields, this add null for weather fields.

What you have to do is only installing like this:

gem install fluent-plugin-weather

Then fluent automatically loads the plugin installed.

<match weather.**>
  type weather
  api_key #YOUR_WUNDERGROUND_API_KEY
  <weather_types> # write regexp by type(ignore case)
    1 sunny|clear
    2 cloud|overcast|haze|fog
    3 rain|sleet|snow|storms
  </weather_types>

  <store>
    # ...
  </store>
  <store>
    # ...
  </store>
</match>