Kind of related...
One thing I figured out while evacuating from Katrina was that text messages are more reliable communication than using your cell phone during an emergency. While we were evacuating the highways were packed. Everybody was on their phones calling relatives and things so it was pretty much impossible to get a call through. Too many people on too many phones with too few cell phone towers.
Interestingly enough, text messages would go through just fine. We were able to get in contact with family to let them know what was going on even if we couldn't give them a call.
Texts are sent in the control protocols, not the voice bearer of the actual call. It's a single frame. This is why I always have a hardline - the standards for their uptime and resistence to natural disasters is pretty hardcore.
I do make sure I have enough food for 3-6 months and a good source of water and a means to drink it. Generators and fuel to survive two weeks without power and other fuel to cook if need be after I'm out of fuel. Along with good first aid.
Want to see all hell break lose? Large scale power outage for more than a day or two let alone a month (happened here). You'd be surprised at how many people simply don't have enough food to go more than a day or two. We're just a few large and long power outages from SHTF.
Day 1, all us preppers are out buying up all the gas we can or traveling somewhere that has power to pump it, hotels are now completely full
Day 2, people start to freak a little, crime starts to tick up, people start getting desperate
Day 3, people really start getting desperate as they are cold, tired, thirsty and hungry, shelters are jammed packed, crime starts to skyrocket
At least that's how it happened when we got a hurricane in KY. Some places were without power for a month. All kinds of undesirables were roaming the neighborhood and that's when I realized I didn't have enough ammo. This is also why I always make sure my home is near a large flowing body of water. My pool will be a good source as well.