She had ignored the warning signs of trouble ahead.

她没有理会警示前方危险的标志。

《牛津词典》

A harbinger, perhaps, of the trouble ahead.

也许，这预示着麻烦即将降临。

youdao

But there may be a different sort of trouble ahead.

但是未来可能会有不同样的麻烦了。

youdao

So there could be trouble ahead for the peace process and U.S.-Israel relations.

VOA: standard.2009.04.17

Warning signs of trouble ahead: John McCain has said that drug companies are the bad guys.

FORBES: Magazine Article

That way vehicles a mile back from an accident would know immediately of trouble ahead.

FORBES: Car Talk

On the surface, the massive debts of South Korea's households and firms might suggest serious trouble ahead.

ECONOMIST: Asian economies