The weather, currently.
This Easter long weekend will be a cool and active one. Friday morning will start out pleasant, with a wake-up temperature near 6°C under a mix of sun and clouds. However, just after the lunch hour there will be a few isolated showers. It will become more of a widespread event for the afternoon, but only for a brief period of time. The rain showers will not be the big story though—it will be the wind. There will be gusts of 40-60+km/h and possibly even stronger in the Niagara region. The forecast high is 12°C.
Friday night: Cloudy with a few showers, possibly mixing with wet flurries early Saturday morning as cold air rushes in. The low will be 3°C.
What you need to know, currently.
If you can think of a frightening natural phenomenon (hurricanes, tornadoes, wildfires), it’s generally safe to assume that climate change will make it more frequent and worse. Hail doesn’t attract the same media attention as hurricanes or tornadoes (although it often accompanies the latter), but it costs the United States around $8 to $14 billion in property damages annually.
It forms most frequently in the hottest summer months, which are especially conducive to violent thunderstorms. The stones themselves are built inside huge cumulonimbus clouds, whose upper regions are below freezing. Updrafts within the storm push raindrops up into this glacial cloud area, where they freeze into ice, then melt and re-freeze as they’re pitched around the layers of the storm system.
The size of the hailstone usually depends on the strength of the updraft—a stronger updraft can cause multiple hailstones to freeze together, whereas a weaker updraft produces more hail that’s generally of a more modest size. The largest hailstone ever found in the United States was eight inches in diameter and weighed nearly two pounds, and a tornado that hit Saledo, Texas on Tuesday left behind a six inch hailstone. Meteorologist Matthew Kumjian of Penn State University told BBC that theoretically speaking, a hailstone could get as large as a bowling ball, although no one has ever found one of that size.
How climate change will affect hailstorms isn’t totally clear yet. A warming climate means more thunderstorms, but it also means that the clouds themselves will be warming—a smaller below-freezing upper layer could mean less hail, but it’s hard to predict how the updraft will behave in intense storms. If you can avoid the larger hailstones, they can be useful in a drought though. A potentially record breaking stone in Texas was reportedly used for margaritas last summer before it could be officially measured.