Sometimes in Germany the forecaster will tell you that tomorrow's weather will be freundlich.
Literally, of course, it just translates as "friendly", but the term gets over the problems encountered by an Anglophone presenter, who must use such words as "good" or "bad", and then discovers that what is good for Jack, who is on holiday, is a disaster for his sister, Farmer Jill, who has been praying fervently for rain for weeks.
A term like freundlich can be non-judgmental - and yet we know exactly what it means.
This use of "friendly" is an example of how words often acquire a specific meaning when related to a weather forecast. Indeed, your humble scribe spends a great deal of time thinking of such things while, like Edward Lear -
He sits in a beautiful parlour
With hundreds of books on the wall;
And drinks a great deal of Marsala,
But never gets tipsy at all.
Take the words "fair" and "cloudy". Both imply relatively uneventful weather, in contrast to the situation were the forecaster expects rain, fog, or even worse - in which case, naturally, she will say so.
But if nothing spectacular like this is expected, she can describe it as one of three terms: "cloudy", "fine" or "fair".
Cloudy as the word implies, means the sky will be covered, or almost so, by cloud; fine is used if very little cloud is expected; and the forecast will specify fair if cloud is expected to cover between about one third and two thirds of the sky.
To take another example, outbreaks of rain are usually foreseen as likely to be accompanied by generally cloudy conditions, but showers are often separated from one another by what may be described as "bright" or "sunny" intervals.
"Bright" in this context is used when patches of blue sky are likely, but cloud is expected to cover the sun for most of the time. "Sunny", on the other hand, implies that there will be extended periods when the sun will be visible. For obvious reasons the terms "bright" or "sunny" are not used when talking about nighttime; "clear spells" is used instead.
No great international lexicological authority has decreed what shall be meant by all these weather-words.
They are intended, by and large, to be interpreted in the same way as they would be in everyday speech, or as they might be defined in the dictionary - but in a rather precise way. The precision, however, is intrinsic to what the forecaster means; whether it is reflected in what is generally understood is quite another question.