There will be a dramatic start to April in western parts of the US, with an influx of warm moist air from the Gulf of Mexico fuelling severe thunderstorms through the first part of this week.
On Monday, storms are forecast to stretch from Texas towards the Great Lakes, with Oklahoma, Missouri and Illinois expected to be most severely affected. The system will then move eastwards on Tuesday, with Kentucky, Tennessee and Ohio expected to receive the greatest impact.
Alongside the torrential downpours, hail and hazardous wind gusts associated with severe thunderstorms, there will also be the potential for tornado formation. April marks the beginning of peak tornado season in the US, with the majority of tornadoes reported between April and June each year.
With severe thunderstorms expected to continue through Monday night and into Tuesday, there is an associated risk of night-time tornadoes, which are more likely to result in deaths than events during daylight.
Behind these storms, a rain system will develop across the Great Lakes on Wednesday and move into the north-east on Thursday, with colder air feeding in from Canada meaning that some of this rain is likely to fall as snow. Snow currently looks particularly likely on Thursday for New England, which has spent the past week repairing damage from one of the most significant winter storms of the season.
On 23 and 24 March, many areas received between 8 and 12in of snow, with parts of Vermont getting totals as high as 30in. Power supplies were significantly affected, alongside reports of road accidents and damage from falling trees.
Storm Nelson has affected western Europe over the past few days, with southern parts of the UK and Ireland, France and the Iberian peninsula bearing the brunt. The strongest winds were recorded on Thursday, with gusts approaching 90mph on the coast of Brittany.
Waves of almost 10 metres were reported in places around the Bay of Biscay, with two deaths in separate incidents on the northern coast of Spain due to people falling or being swept into the sea.
There were also two deaths in Catalonia, where people drowned after being caught up in strong waves. Though winds eased after Thursday, outbreaks of heavy rain associated with Nelson continued to affect France and Spain, with the highest totals seen in Andalucía on Saturday, when more than 80mm was recorded in places.
