How much does Signal Jamming increase scanning times by?

I have a mission to counter the Dark Event signal jamming, which increases scanning times for all six weeks. It certainly seems pretty bad, but it doesn't say how much scanning times are increased by, and I'm having trouble finding an answer either online or by digging through the config files.

I wouldn't be too concerned about this and would just try to counter it, but unfortunately the mission it got assigned too has a ranking of "DIFFICULT" and the "Low Profile" modification which only allows me to bring low ranking soldiers along. So before I decide to gamble on sending a squad of squaddies along to probably get themselves killed, I'd like some idea just how much of a threat this Dark Event is.