NAO: North Atlantic Oscillation. One of the main teleconnections, the NAO can have significant impacts on the weather here in New England. The NAO represents a north/south swing in pressure across the Atlantic. When the NAO is in a positive phase, upper level ridging takes over Eastern North America and brings warmer temperatures. The opposite happens when the NAO is negative. While the NAO can have big impacts on our weather, other teleconnections can negate the effects of the NAO.