Explorations: Finding Climate Data
Climate is often defined as “the average weather,” but it’s more complicated than that. A better definition is: statistical weather information that gives you not only averages over a particular time but also data that shows you how the weather varies.
You might be interested in climate information for a place you are planning to visit or move to. You’re likely to ask, “what’s the weather like” in the place at the time you plan to visit. What meteorologists call the climate “normals”—really averages, not what the weather was like at the same time last year, which could have been unusually hot, cold, wet or dry.
Normals are 30-year averages plus information on extremes, which refers to the highest and lowest temperatures and wettest and driest periods of time over a 30-year period. The temperature extremes are a good guide to the very worst you can expect since such daily high and low records are seldom broken by more than one or two Fahrenheit degrees.
The U.S. National Climatic Data Center (NCDC), which is part of NOAA, collects, stores, and makes available climate data from around the world.
For data for locations in the United States, you can go to the U.S. Climate Normals Web page. The NCDC home page for links to a huge amount of weather data around the world.
The amount of data might be too much if all you want to know is what kind of weather to expect on your vacation. A much easier way to obtain such information is to go to an online weather Web site. Probably the best for climate information is the Weather Underground’s Trip Planner page. You type in the name of the place and give the dates you are interested in. This brings up a good amount of useful data, including averages and extremes for that place and time of year. The information even includes information such as: “There is a 90% chance of a Warm Day (temperature over 60�F/16�C) (105 days out of 117 in historical record).” Data from other nations, as well as the United States, are available.
A handy book for travelers or anyone who’s interested in the climates of places around the world is Robert Henson’s The Rough Guide to Weather 2 (London: Rough Guides, 2007). This book’s combination of tables of data and brief descriptions of weather on all continents, including Antarctica, give a global traveler a good idea of how to pack.