Pretty much whatever you can imagine, and usually you can't tell what direction it's coming from. Major cities are usually coastal, so it may be easier for the the TITANs to melt the poles than to directly assault them. Definitely we know there's crazy weather things going on. Superhurricanes, earthquakes, armies moving back and forth, slews of refugees, militia platoons, common thugs and gangs. The TITANS are smart, so expect them to focus more on systempunkts and misdirection than direct confrontation.

Honestly, it might play more like a high tech new world of darkness or call of chthulu campaign than what you might expect from EP, at least in initial tone as the horror of the TITANs actually kicks in. A better question to ask: how do you interpret the TITANs as a GM? that will greatly affect the tone and the events that transpire. I can only really speak from how I'd do it as I like to think that the Fall wasn't a sudden event, but rather a really long, protracted thing that started out quiet in the background and just steadily gained momentum until humanity was unable to stop it. As the setting points out, there was a lot of prominent 'foreground' political turmoil happening on Earth during the period. Then again I also like the idea of the mid to late fall being a months long actual armed conflict between humanity and the TITANs because the idea of stalwart humans holding the line long enough to get people offworld appeals to me. I didn't say I had good ideas for what you need in your campaign :P