Probably the most difficult task in creating any GIS system is getting data in the correct format for the system to use. When it comes to meteorological data and its many formats, this theorem holds true. The Iowa Environmental Mesonet [IEM] is working to provide datasets in GIS formats as well as visualizing the datasets in GIS systems.

The IEM is a project to gather, compare, disseminate, and archive environmental observations made in the state of Iowa. Unlike other mesonet projects, the IEM does not own or operate any of the automated stations. Providing data and products to meet end-user's needs is the ultimate goal of the IEM.

The IEM is currently utilizing University of Minnesota's MapServer software to build GIS web applications. MapServer (http://mapserver.gis.umn.edu) is an OpenSource environment for building spatially enabled Internet applications. Built on other OpenSource components, MapServer provides a fast and easy way to develop GIS based web applications.

The IEM continues to build GIS applications using MapServer. To date, we have built an online Iowa tornado database, a spatial precipitation reference system, a zoomable/overlay plot of NEXRAD imagery with surface observations, and a dynamic mesonet station locator system. The backend data for these applications are stored in ESRI Shapefiles, TIFF raster images, and a spatial PostgreSQL database. MapServer combines these datasets into dynamic images for web display.

The IEM also distributes some of its datasets in GIS-ready formats. Shapefiles can be downloaded containing, for example, real-time weather data, yesterday's summaries, or climatological normals. Current NEXRAD imagery can be obtained in a geo-referenced format or in an encoded shapefile. Collaboration has been initiated with the State of Iowa GIS Council and work continues with the Iowa State GIS Lab.

The IEM GIS effort can be found at http://mesonet.agron.iastate.edu/GIS/ .