If you are traveling to Belize on USAirways, you will still be able to buy trip insurance, but it probably won't cover you if USAirways goes bust ... the policies don't cover pre-existing conditions (e.g. if you bought a trip interruption policy AFTER the hurricane has already formed...).
If you are still interested, you can buy a policy online from a number of insurers; the only one with which I have personal experience is TravelGuard (www.travelguard.com
). Be sure to read the fine print so that you buy a policy which covers the risks that you are concerned about.