Doom and gloom
Definition 1 of 2
Pro Tip 1/3Mood Expression
Use 'doom and gloom' to express a collective sense of fear or worry that affects a group's mood. 
After the news, there was a sense of doom and gloom among the staff.
Pro Tip 2/3Not Literal
'Doom and gloom' is not about actual disaster, but describes a general feeling of negativity. 
People talk about doom and gloom, but there were no real catastrophes.
Pro Tip 3/3Conversational Use
This term is more commonly used in casual conversation rather than formal writing or speeches. 
In our coffee chats, we try to avoid topics that bring doom and gloom.