The eastern half of the US has been gripped by an exceptional early winter cold spell this week, breaking a multitude of low-temperature records. Eighty weather stations across the deep south either tied or broke their daily minimum record on 11 November. Jacksonville in northern Florida experienced temperatures as low as -3C early on Wednesday morning, 17C below the average minimum for the time of year.
The cold outbreak also brought extreme snowfall to parts of Illinois, Indiana and Wisconsin. Areas along the southern and western coasts of Lake Michigan experienced a phenomenon known as lake effect snow on Monday. This develops when cold air – which covered the US this week – moves over the relatively warm water of a lake or inland sea. This produces convection and heavy showers that move inland downwind of the lake, and can continue for hours or even days on end.
