To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Share Embed Share URL Video File Node URL Embed Code <iframe title="MRC TV video player" width="640" height="360" src="https://www.mrctv.org/embed/41111" allowfullscreen></iframe> NBC Nightly News anchor Brian Williams to NBC WeatherPlus meteorologist Bill Karins, May 12. Karins discounted global warming as a cause of increased tornado sightings.
