✔ 最佳答案
This is normal. Every few years we get a cold snap in April. In 2010 I was working on a road scheme in Kent and we were SNOWED OFF for several days in April. Less than three weeks later it was over 30. That felt crazy!
In the bigger picture though, later springs are becoming a thing in Britain. It gets cold later in the year than it used to so all kinds of plants now flower in December that used to either have died back or wouldn't flower until the next Spring, so plants we never used to see together now co-exist. It's also changed the order in which some spring flowers come. I knew we were going to have a cold spring because my bluebells are very late this year.