A wintry blast of snow, hail and gales is set to hit the UK in the run-up to the May bank holiday weekend, according to forecasters.Temperatures will plummet tomorrow and are expected to remain unseasonably low until the middle of next month.The Met Office is predicting “heavy and wintry” showers and widespread overnight frosts from Tuesday next week, with northern parts of the UK the worst hit. Eleanor Bell, from The Weather Channel, said an easterly-moving area of low pressure, which is currently over Iceland, “will result a strong cold northerly plunge into north-west Europe in between the high and low pressure and as a result will pull temperatures below normal for the time of year”.”Temperatures will be around 2 to 5 degrees below normal for the time of year over the UK and 4 to 7 degrees below normal for northern mainland Europe,” she said.“A cold northerly flow will affect all areas mid-week with a sharp frost in sheltered areas. Further snow showers will affect northern areas, as well as the east coast and exposed western coastal areas.” However, this brought about an early start to the birch pollen season, which may now be tempered by the drop in temperatures, bringing hope of a respite for hay fever sufferers.The driest and brightest weather is expected to be in the west next week “probably spreading to the rest of the country” by the weekend, according to the Met Office. The gloriously warm start to spring has come to an endCredit:EPA Snow showers will affect northern areas, as well as the east coast and exposed western coastal areasEleanor Bell, The Weather Channel The Met Office said the risk of frost will continue into May, but that the early part of the month is likely to be drier than usual.Once the cold temperatures ease, around the middle of the month, temperatures are then predicted to be higher than average. Low pressure will bring a windy end to Sunday in Scotland, then it gets much colder for all next week as arctic air arrives. #WinterReturns pic.twitter.com/ML20XrMLmA— Met Office (@metoffice) April 21, 2017 Conditions are expected to dry out for the three-day break, but temperatures will only rise very gradually.The cold spell follows a gloriously warm early start to the spring, which saw heights of 25C. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.