Proper usage of "trying"

You can express the idea of a near-freezing state of the water in a bucket, without attributing human-style intentionality to the water, by saying:

The water in the bucket is on the verge of freezing.

Merriam-Webster's Eleventh Collegiate Dictionary (2003) defines anthropomorphism as follows:

anthropomorphism n (1753) an interpretation of what is not human or personal in terms of human or personal characteristics: HUMANIZATION

It's easy to see why scientists generally disapprove of anthropomorphism, at least in the abstract. But it's also easy to see why people (including scientists) find anthropomorphism so hard to avoid: Many of our most common verbs—try, want, desire, hope, ask, wish, love, demand, refuse, insist, agree, etc.—are bound up in the way human beings respond to stimuli.

Scientifically it is ridiculous to say the water is 'trying to freeze'.

But idiomatically that sort of expression is used all the time.

In Britain it is quite normal to say, of the weather, 'it is trying to rain' and/or "the sun is trying to come out". They are accepted idioms.

And the state of the weather is the first thing that a large number of British people remark upon when they wake up. It goes with the morning cuppa. What it is doing out of doors is a national obsession, in all four seasons of the year.

Yes, it is grammatically correct, and it is meaningful.

No, of course water does not have an intention. But it can make figurative, poetic sense to talk about it that way - and people do.

This is not unusual, and everyone (I hope) understands what is really meant by such an expression: It is as if the water itself is trying to freeze but has difficulty succeeding.

A similar, very common expression is to say that the sun is trying to come out (from behind the clouds). No one really thinks of the sun as trying anything, but the image is a good one, so people use it.