something tells me - Phrases/Idioms
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
I suspect, I have an intuition, as in Something tells me that she's not really as ill as she says, or Something told him that it was going to snow.