Lotta good replies here, from some knowledgable folks.....Now, another viewpoint:
As mentioned, HAND-HELD CB's aren't really good for what you're looking for....CB's are the solution, with a little "help", such as the link below:
http://www.copper.com/cart/index.php?cPath=61&osCsid=c129b372304cb873e7a092b4fb5addd2
Here's my setup in my daily-driver:
A Galaxy DX-959 AM/SSB rig:
A fairly nice Power/Echo mic:
A 4-foot Firestick II antenna:
And, the "kicker" that makes the long-range comms "good-to-go":
All of my families' vehicles have a similar setup, and we have tested these under all weather conditions, 30-45 mile comm ranges are achievable 100% of the time.....
Now, before the ARRL Crew starts flaming me, let me say that using linear amplifiers on CB frequencies IS illegal, but in times of natural disasters/emergencies, do you think that the FCC is gonna be looking for a "pirate station"? They'll have bigger fish to fry, and you can rest easy, knowing that you can communicate with your group/loved ones, WITHOUT repeaters or outside help.....I've heard all the rumors that cell phone usage is suspended during times of natural or man-made disasters in an area, and that only police/fire/first-responders will have working phones......conspiracy-theory or not, I take NO CHANCES when it comes to communications with my loved ones, or gathering intelligence.....
Be forewarned, there ARE dangers using these power levels at that frequency, but with some good training and knowledge, these dangers can be mitigated to safe levels.....As for other CB's cramming the channels with static and chatter, if you have enough power on your linear, you can blow them off the air.....set your squelch high enough, you won't even hear their puny 5 watts output, or their little "stinger boards"....
One thing you MUST make sure of when using a linear, is that your SWR (Standing Wave Ratio) is VERY low, or you'll burn out your output transistors on the linear in a hurry....check your SWR at standard power output, THEN boost the signal after you're sure it's low.....The ARRL Handbook is a GREAT source of info, that doesn't just apply to the HAM crowd.....
Finally, I do NOT use my linear amp for daily driving on the roads, the 5/12 watt limits are more than adequate for most usage......However, I test my linear at least once a week, usually in the wee hours, so as not to disturb any neighbors with my chatter, and have a firm knowledge that if needed, our comms will always be there in times of dire need....I do admit, there have been times when I was driving a lonely stretch of road at night, and some trucker had a "stinger board" on his CB (maybe 50 watts output or so), and after 5 minutes of his noisy, inane chatter, I kicked up to about 400 watts, and blew his a$$ right off the channel....
Just an alternative solution to your problem.....Let the Flames begin.....
DocZeus