Post-Tropical Cyclone

A post-tropical cyclone is a former tropical cyclone that no longer has enough tropical characteristics, such as a warm core and a tropical energy source, to still be classed as tropical, after undergoing what meteorologists call extratropical transition and taking on the frontal structure typical of mid-latitude storms. Despite the change in classification, post-tropical cyclones and their remnants can keep producing high winds and heavy rain, so losing tropical status does not mean the danger has passed. The category splits into extratropical cyclones, which are frontal and can still carry hurricane-force winds, and remnant lows, non-frontal systems of weaker winds made up mainly of stratocumulus cloud, with systems that have winds over 34 knots but no fronts simply labeled post-tropical; the term was coined by Canadian meteorologist Peter Bowyer in 1998 and formally adopted by the US National Weather Service in 2010.