It seems that OpenWeatherMap has changed the API processing. I am using the weather binding to gather the data for two different locations and nearly always one of the locations has a lot of “undefined” values and the openhab.log shows a http error 429 for the location.
This does not happen, when trying to use DEBUG or TRACE inside the weather binding. The problem can be avoided (partly) by defining different time schedules for the two locations – than a 429 error happens only, when the two locations are refreshed at the same time (common multiple of the schedules).
A more permanent fix probably may be achived, when the binding is changed to retrieve the data only for one location per minute.
This at least is valid for OpenHAB 1.7.1 and 1.8.1…
have fun,
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