The phrase "a difficult hour for" is correct and usable in written English.
It can be used to describe a challenging or trying period of time for someone or something.
Example: "It was a difficult hour for the team as they faced unexpected setbacks during the project."
Alternatives: "a challenging time for" or "a tough moment for".
"This is a difficult hour for all of us, especially those of us who know the president and respect his tremendous contribution to the state," said Prime Minister Ehud Barak.
"The government is doing all it can for rescue and relief on a war footing" in a "difficult hour" for Nepal, Mr Koirala told Reuters news agency.
While it is a difficult hour for Obama, his poll numbers make him look like Mount Rushmore compared to those of House Republicans, who are so unpopular they could be swept aside in a landslide.
"It is a challenge and a very difficult hour for Nepal".
It well may be that in a difficult hour, Pinned down by pain and moaning for release, Or nagged by want past resolution's power, I might be driven to sell your love for peace, Or trade the memory of this night for food.
Venezuela and the world will thank you; success will depend on each one of us doing our part in this difficult hour for the country.
"In these difficult hours for our society we must all - the state and the citizens - support the people among us who are desperate," he said.
As the House convened to consider a resolution honoring the dead and wounded in the Arizona shooting, the speaker, John A. Boehner of Ohio, said, "These are difficult hours for our country".
City's defeat closed a difficult 24 hours for Roberto Mancini following reports in Spain that he will be replaced by Manuel Pellegrini, the Málaga coach, in the summer.
Hey team, I know it's been a difficult 24 hours for all of us….
The videos bookended a difficult 24 hours for the Romney campaign.
