Jet stream puts UK under pressure

18th January 2020 Last updated at 15:57

An unusually high pressure reading was recorded early Monday morning when the barometer reached 1050.5 millibars (at sea level). This is the highest recorded since 1957. For those who like numbers, when compared to the global average pressure reading of 1013mb, that's quite a difference.

Clear blue sky over Eastbourne pier
BBC
High pressure brings fine and settled weather

The Atlantic jet stream makes and moves around our areas of high and low pressure and so is crucial in determining our day-to-day weather. Strong jetstreams are often held accountable for being responsible for stormy weather, but are less frequently discussed for bringing dry, fine and settled weather.

Fast jet stream and high pressure

An incredibly strong Atlantic jet stream fires up this weekend, with peak winds hitting an astonishing 238mph in the central Atlantic. With the air ahead of these peak winds only moving at a relatively modest 115mph there will be something of a pile up in the upper atmosphere, 6 miles above the UK. This accumulating air is then forced to descend down through the atmosphere towards the earth's surface where it can collect quicker than it can flow away; an area of high pressure will form. On Monday this area of high pressure over the UK is expected to reach 1050mb, the highest UK pressure reading for 28 years, and not far away from the UK record which stands at 1053.6mb recorded at Aberdeen on 31 January 1902

Unlike very low pressure when people sometimes complain of headaches or joint pain, there are few noticeable physical effects of unusually high air pressure. However, after an extended period of wind and rain, a few days of fine and settled weather is a welcome by-product.