Site Information


The National Severe Storms Laboratory Web pages may contain links to external (non-government) Web sites because we believe certain sites may provide additional interesting and relevant information that relates directly to our mission. NSSL does not endorse the information, products or services found on another site nor is it responsible in any way for the information found there. Furthermore, NSSL does not guarantee the privacy of any information collected there.

Some NSSL-sponsored research performed by CIMMS scientists working at NSSL is presented in Web pages that reside on the University of Oklahoma's Cooperative Institute for Mesoscale Meteorological Studies Web site ( links to these pages are external, the directly-linked content is consistent with NSSL guidelines and policies and represents a significant part of the research carried out at NSSL.

Additionally, any mention of commercial products within NSSL web pages is for information only and does not imply recommendation or endorsement by NSSL.

External links to data and information must meet the following criteria:

  • links are necessary for and material to the presentation of information
  • reasonable steps are taken to ensure the presentation is accurate, relevant, timely, and complete
  • reasonable steps are taken to assure that links remain active or otherwise continue to provide the level of quality (including objectivity, utility, and integrity) as intended by the agency and expected by users.
  • do not constitute an endorsement as described in the NOAA Disclaimer.

The information on NSSL web pages is in the public domain, unless specifically noted otherwise, and may be used freely by the public. 


Most pages on the NSSL website have been reviewed and revised to be accessible to individuals with disabilities in accordance with Section 508 of the Workforce Investment Act and the Americans with Disabilities Act. If you have difficulty accessing information or using adaptive technology with any of our Web pages, please report it via email to the NSSL Webmaster or by telephone at 405-325-6907. We will make every effort to make them accessible to you as quickly as possible.

Computer Security

This is a Department of Commerce computer system. Access or use of this system by any user, whether authorized or unauthorized, constitutes consent to security monitoring and testing. Information may be intercepted, recorded, read, copied and disclosed by and to authorized personnel for official purposes, including criminal investigations. All activity is logged with your user name and IP address.


Unless otherwise stated data contained on this site is the property of the Department of Commerce and may not have been processed for quality assurance. 

Privacy Policy

Occasionally the NSSL website may set cookies in your browser. “Cookies” are small bits of text that are either used for the duration of a session (“session cookies”), or saved on a user's hard drive in order to identify that user, or information about that user, the next time the user logs on to a Web site (“persistent cookies”). This website may set cookies to remember a visitor's display preferences and customize the user's online experience, in accord with Department of Commerce policy as stated here. Acceptance of cookies by your browser is not required to successfully use or navigate the NSSL website.

NSSL uses Google Analytics, a third-party web measurement and customization technology as defined and organized by the federal government’s Office of Management and Budget (OMB) “Guidance for Online Use of Web Measurement and Customization Technologies” (OMB M-10-22,

Here’s how it works: Google Analytics places a cookie (see above definition) on your computer, so that it can recognize your computer if you visit our website in the future. This cookie does not collect personal identifying information. This is considered a Tier 2 service in the OMB guidance. Google Analytics does not collect personally identifiable information through its cookie and does not combine, match, or cross-reference information with any other information. Please review the Google Analytics privacy policy for additional information. Visitors who choose to disable this web measurement tool will still have full access to the NSSL website. While the details vary from browser to browser, most modern browsers can be set up to accept, reject or request user intervention when a site asks to set a cookie. Google Analytics uses a cookie that begins with: _utm.

Read the full NOAA Privacy Policy.

Supporting Applications

These file types require additional software to view the content through your browser. If it is not already installed, you can download any of the following applications free from their publishers by clicking on the links below. Follow the installation instructions provided for each application.

  • Adobe Acrobat Reader is required to read Portable Document Format (pdf) files.
  • Apple QuickTime plays many kinds of files, including video, audio, graphics, and virtual reality (VR) movies.
  • Google Earth  is a free 3-D interface required to view .kmz files that combine satellite imagery, maps and Google Search.


Some photos on this site are used under CC BY_SA 3.0 licensing. These are indicated in the photo caption or watermark.

Vector "home" icon on the NSSL 50th anniversary pages made by Icomoon from is licensed under CC BY 3.0