Low pressure also expected to raise temperatures in eastern Canada and north-east US, while temperatures plummet in west

After a lull in recent weeks, storm season in the US has begun to ramp up again, with 100mph winds and tennis ball-sized hail hitting Kansas on Sunday. It has been a busy season so far in terms of severe storms, with late spring into early summer typically bringing the greatest risk for tornadoes across the plains and midwest. An area of low pressure moving in across the central US, combined with rich moisture streaming in from the Gulf of Mexico, will probably continue the threat of tornadoes and large hail across numerous states. On Tuesday in particular, this severe weather risk may extend from Oklahoma all the way up to the Great Lakes.

This setup of low pressure could lead not just to a large outbreak of severe weather across the US later this week, but also to a sharp temperature gradient across the US and Canada as the warm air is fed into higher latitudes. In eastern Canada and the north-eastern US, temperatures are likely to reach 10C above the average for the time of year. Cities such as Ottawa and Detroit could have daytime maximum temperatures of 30C by Wednesday.