Explainer: What are bomb cyclones and how do they form?

A bomb cyclone’s winds can reach hurricane force – 74 miles (119 km) per hour – and stronger. These storms tend to form during winter and can spawn copious amounts of precipitation. They have life spans of about a week during which they grow to peak intensity over roughly four to five days and then dissipate over the last two, according to Jon Martin, a professor of meteorology at the University of Wisconsin-Madison.