National Weather Service United States Department of Commerce

NOTICE: PLEASE EXCUSE OUR DUST! This web page is currently still under construction.


Starting January 1, 2017 as we migrate web pages, some products and services linked from these pages may become temporarily unavailable. Products should continue to be accessible via FTP. We apologize for any inconvenience this may cause.

What is XML?

XML stands for eXtensible Markup Language (XML). It is the standard used for World Wide Web (WWW) data exchange. It is well supported by public domain software. The format which will be used for generating the new XML products will be a Digital Weather Markup Language (DWML)-based version of XML. The DWML is used to share weather data. The specifications were written with enough flexibility however to accommodate other environmental science applications. DWML consists of three main parts: a header section containing a description of the product, a temporal definition section, and the forecast data section. For a complete description of DWML see: MDL_XML_Design.pdf 


On inspection, there are similarities between XML and HyperText Markup Language (HTML). However, XML is used to describe the data, whereas HTML is used to describe the format or to display the data.