"impending rain" is a correct and usable phrase in written English.
It is often used to describe rain that is expected to happen soon or is likely to happen in the near future. It creates a sense of anticipation or foreboding. Here's an example: "The dark clouds and cool breeze signaled the impending rain, causing everyone to rush to get indoors."
The air was heavy and gray with impending rain.
But Wednesday morning came and brought with it clouds and impending rain.
Ms. Pless, who lives with her husband and a physically disabled son, said she was anxious about the impending rain.
Evacuees in the towns below Paradise, many of whom are living in tents, are also wary of impending rain.
"Terrible, terrible, terrible," he muttered at one stage early in the third set before the roof was closed because of impending rain.
A year-round spring wept from the face of the rock, and the dampness of it filled the house with the smell of wet leaves and impending rain.
By E. B. White The New Yorker, December 8 , 1928P. 21 There are certain signs in N.Y. which tell of impending rain--the Metropolitan chimes ring a certain way, the liners' whistles sound more clearly, and in Wall Street, the smell of the coffee on the docks comes more strongly.
In his novel "The Names," author Don DeLillo wrote of impending midsummer rain: "There's always a period of curious fear between the first sweet-smelling breeze and the time when the rain comes cracking down".
If they didn't run out of oxygen first, impending monsoon rains threatened to drown them.
As for it being a potential omen of impending flash-flood rains that will wipe out nearly all of civilization (like in the Bible), Huibers says his ark will serve as a "journey of hope".
Over the last six months, outreach workers have visited encampments in the county's five watersheds to spread news of impending dangers from El Niño rains.
