Snow descended on Reading this morning (Wednesday, March 8) and University of Reading researcher explains why snow is so hard to predict.

Late last week, Met Office forecasts warned snow was coming to the south east, but it was not clear when it would start falling. 

Postdoctoral Research Scientist in Meteorology at University of Reading, Dr Rob Thompson, has previously explained why snow is hard to predict.

He said: “The UK’s erratic winter weather is caused by two things: its location and the fact that small differences in temperature can cause dramatic changes to the forecast.

“The UK is located right where a number of different global weather systems converge. Unlike many places in the world, freezing weather in Britain is generally accompanied by northerly or easterly winds. But heavy precipitation (liquid or frozen water) is usually from the west. Colder weather in the UK makes precipitation less likely. Which is why if we see snow, it often arrives as a light shower or flurry. Thick snow usually happens when precipitation from the west hits cold air from the east or north.

READ MORE - Snow in Reading: How the town was affected by Arctic weather

“Forecasters today can predict widespread precipitation down to the hour. So mapping out wet weather is not the problem. The issue is that British winters make it a lot harder to tell what form precipitation will take when it reaches us. This means predicting whether we will get sleet, freezing rain, snow or just rain. A small difference in temperature makes a really big difference to the outcome.”

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