If you’re planning to hold an important event outside where there will be a large gathering of people with food, drinks and speeches, you want to be sure you’ve thought of everything and there is no major or minor catastrophe on the day. One thing you can definitely predict with a degree of certainty is the unpredictability of our great British weather. There’s just no way you can be sure what the weather is going to be like in this country, despite what the forecasters say. We’re an island with a maritime climate and our weather is variable, to say…