A map can represent data from an area on a flat surface. The part of our Earth system most frequently mapped is the atmosphere. Weather—the state of the atmosphere at a particular place and time—needs constant monitoring because it perpetually changes as weather systems evolve and move.
Awareness of what the weather is and is likely to be has numerous benefits. Weather can be hazardous, causing injuries, death, and loss of property. Weather maps are valuable analytical tools for informing people about current or future conditions.
In the United States, the National Oceanic and Atmospheric Administration’s National Weather Service (NWS) distributes observational data directly to the public and through private-sector partners. For example, NWS weather maps are available on the Internet.
Revealing one of the most devastating weather disasters in U.S. history, the map used in this activity offers an analysis of surface weather conditions at 7 a.m. EST on October 29, 2012. The “bull’s eye” pattern of isobars (lines of constant pressure) depicts the low-pressure center of Superstorm Sandy, which rushed ashore in New Jersey and New York that evening.
There are numerous sources of weather maps extending from the surface of the Earth to the upper atmosphere. For simplified versions, see Datastreme Atmosphere at www.ametsoc.org/amsedu/dstreme/. For continuously updated weather maps that display surface observations and forecasts, see www.hpc.ncep.noaa.gov/html/sfc2.shtml.