Can tornado dip down into ditches?

Technically they don't dip into ditches and even if they did the windspeed would be far less in the smaller space. They say that if you are in the open, a ditch is your best chance for survival. It would still eb pretty scary though. I don't know and have never heard anyone talk about how much of an effect the suction from the tornado would have on you in a ditch. Hopefully neither you or I will ever have to find out.