well the documentation doesn't tell anything about this... besides of:
Time Offset and Timezone – Use these options to define the time zone and to select the offset, or time differential, between the target city daylight savings time (DST) value with that of the Google data source. An additional option here is used to set the time at which the day and night icons are displayed.
... but it is not really explained how the settings should be.
If I have the correct WOEID .. I shoudn't need a Timezone or Time offset setting... or do I need it if I am located in Europe?