"....It's hard to believe the prediction of a Global Warming catastrophe when an arctic chill of winter weather has paralyzed much of Europe in December. As a result, average daily highs across the continent have dropped anywhere from 5C to 10C, according to AccuWeather. These cold conditions have reignited fears across Europe of an impending Little Ice Age similar to the one that appeared during the Middle Ages..."
Zonal Index -- A measure of the strength of the middle latitude westerlies.
High Zonal Index -- Very fast westerlies, low amplitude waves, zonal flow.
Low Zonal Index -- Slow westerlies, high amplitude waves, meridional flow.