Idiom Usage:
This idiom can be used in two forms:
"to be under the weather"
or
"to feel under the weather"
Either form has the same meaning.
The "feel" form must be used for the progressive verb tenses.
It can be used for all verb tenses.
The "be" form can be used for all tenses except the progressive tenses.
"To be a
little under the weather" or "to be under the weather" describe the degree to which a person is not feeling well.
This idiom can be used to describe psychological conditions.
For example, if a person is sad or a little depressed, they can
be feeling a little
under the weather.