The characters combine to create a powerful image. It's not just “wind and rain” (风雨). The wind and rain are 交 (intersecting) and 加 (adding) to each other's intensity, creating a much more violent and overwhelming storm. This intensity is key to both its literal and metaphorical meanings.
`风雨交加` is a classic example of how Chinese culture uses vivid natural imagery to describe complex human experiences. The struggle against the elements is a universal theme, and this idiom captures the feeling of being overwhelmed by forces beyond one's control. A useful comparison in Western culture is the idiom “when it rains, it pours.” Both describe a situation where multiple bad things happen at once. However, there's a subtle difference in feeling:
This idiom reflects a cultural appreciation for resilience (the ability to withstand the storm) and a pragmatic understanding that life often involves periods of intense hardship.
`风雨交加` is a common and versatile idiom used in both written and spoken language.