Of course you don’t, but you can calculate the risks of one disaster vs. another and one site vs. another with some simple research into natural disasters.
Earthquakes are more likely near the edges of tectonic plates than they are in the interior, especially if the plates are moving together and pushing on each other (and there is a history of earthquakes and activity). You can quickly identify areas at high risk by looking at a tectonic map, such as the one over on ThinkQuest. One quickly sees that high risk areas are the west coast of North and South America, South East Asia, Japan, and the island domains north of Australia, as per the Global Seismic Hazard Map over on Countdown.org.
You can get a list of volcano activity reports from the Smithsonian Institute which maintains a USGS Weekly Volcanic Activity Report. Most are usually in the Ring of Fire, which encompasses the high-risk earthquake zone around the Pacific. GeoCodeZip.com Google maps them for easy viewing.
Coastal areas near sesimic hazard (earthquake) zones in the oceans are at the greatest risk of Tsunamis, which tend to build up in power and force as they approach shallow water and land. This says that some of the riskiest araes are on the Ring of Fire in western North and South America, Japan, and south-east Eurasia in the island domains North of Australia. More information on Tsunami Risk Zones can be found over on the International Tsunami Information Center.
The greatest risk centers for hurricanes are coastal areas near the equator where hurricanes are normally a problem. The east coast of the US is particularly susceptible to hurricanes. The Global Weather Oscillations site specializes in in hurricane risk probability zone forecasts for the US and the risk zones for the coming year can be found on the Global Weather Cycles web site. The National Weather Service tracks the 10 global hot zones over on the National Hurricane Center site and a review of historical data will tell you how risky a certain area is.
Tornados can occur anywhere in the world (including Antarctica, although this is the one continent where a tornado has not been documented) when the atmospheric conditions are exactly right. However, the most at risk zones are the middle latitudes between about 30 degrees and 50 degrees North or South where cold polar air meets warmer subtropical air and generats convective precipitation along the collission boundaries. As a result, taking weather patterns into account, the most at risk areas are the United States, western Europe, South Africa, the eastern and western coasts of Australia, New Zealand, the eastern and western borders of China, the estern coast of Argentina, Japan, South Korea, and the Philippines. Good information on tornado climatology as well as a great map of global risk zones is found over on the National Climatic Data Center site.
Blizzards can be bad, but generally don’t do much in the way of lasting damage. Ice storms, on the other hand, can do severe damage to infrastructure on a wide scale by downing power lines, and grids, damaging structures from the sheer weight of the ice, and even taking down trees. The most at risk areas tend to be Canada, the US, the UK, and most of Northern Europe and Russia.
Floods are not limited to the coastal variety, and can happen anytime the water level rises too quickly. Thus, in addition to worrying about flooding in coastal areas as a result of a tropical storm, hurricane, tsunami, or storm surge (tropical cyclone), flooding inland can occur from intense thunderstorms, sustained rainfall, or rapid snow melt. Thus, all of the coastal areas identified in your hurricane and tsunami risk lists are at risk at flooding plus any area with a history of flash floods, sustained rainfall (like they get in India during Monsoon season), or rapid snow melt (in Northern Canada) are at risk of floods.
Wild Fires can occur on any continent at any time whenever the conditions are right and are likely to follow heat waves, droughts, and cyclical climate changes (such as El Nino) and high-pressure ridges. They are most common in climates that are sufficiently moist to allow regular vegegation growth but where extended dry, hot periods are also present. This keep parts of Africa, South America, South Eastern Eurasia, and Eastern Eurpe at high risk, but parts of the Southern US, Mexico, India, and Australia also enter the high risk zone on a regular basis.
In other words, there’s no excuse for not knowing which suppliers are at risk of which natural disasters and how great that risk is. (Some historical research will give you frequency of disasters in the area and a local climate institute likely has probabilities of occurence for the event, such as once every twenty years.) So while it may be hard to say how risky your supply chain is from a holistic perspective (as some financial or political risks may not be identifiable until the last minute), it should not be hard to say how risky it is from a natural disaster perspective.