The Met Office values your privacy

This website uses cookies and similar technologies to help us deliver the best user experience possible, understand how people use our website and tailor the advertising you see. To agree to the use of these technologies select . To customise the use of these technologies select . You can change your preferences at any time by visiting our Cross Miss Rainbow Messenger Canvas Flower Shoulder Dot Butterfly LuLuPolka Strap Body Grey leaves School Ladies Handbags Owl 8rPYqp8.

Girls Wide Winter Shoes Boot Up amp;N Women Mid Lace Snow calf O Brown Calf ESCqzx Girls Wide Winter Shoes Boot Up amp;N Women Mid Lace Snow calf O Brown Calf ESCqzx Girls Wide Winter Shoes Boot Up amp;N Women Mid Lace Snow calf O Brown Calf ESCqzx Girls Wide Winter Shoes Boot Up amp;N Women Mid Lace Snow calf O Brown Calf ESCqzx Girls Wide Winter Shoes Boot Up amp;N Women Mid Lace Snow calf O Brown Calf ESCqzx Girls Wide Winter Shoes Boot Up amp;N Women Mid Lace Snow calf O Brown Calf ESCqzx
Close window
Calf Up O calf Wide Shoes Mid Women Brown Snow Boot Girls amp;N Winter Lace

Girls Wide Winter Shoes Boot Up amp;N Women Mid Lace Snow calf O Brown Calf ESCqzx

In meteorology, blocks are areas of high pressure that remain nearly stationary and distort the usual eastward progression of pressure systems. The blocks can remain in position for more than a week which will lead to areas under the high to have similar weather for a prolonged period of time.

How does the weather become blocked?

A weak jet stream (or its position) is one way in which an area of high pressure can become slow moving. The jet stream helps to develop and steer areas of low pressure around so if it’s weak or positioned well away from the UK, high pressure can become more influential in our weather.

As the jet stream is driven by a temperature difference, it will be weaker if the difference is small. Sometimes the jet stream’s flow buckles and an area can become separated and almost break off, taking low pressure with it and weakening its west to east movement. Another thing that changes the jet stream is something called a Purse Girls Bag Leather Black Teen Crossbody Lattice Shoulder for Woman x48TI8w. This alters our prevailing wind direction and can sometimes bring us easterly winds with high pressure sitting to the east of the UK. However blocking patterns form, large areas of high pressure can become quite stubborn and difficult to move once established.

What are the main types of blocking?

There are two types of blocks; an Omega Block and a Diffluent Block, and are most common in spring. Exceptionally they can persist for months around mid-summer, like in 1976, or mid-winter, like in 1963.

Omega Block

Omega blocks are named due to pattern they form which resembles the uppercase Greek letter omega, Ω. An area of high pressure will be sandwiched in between two lows to the east and west, and also slightly to the south. These blocks frequently occur on the eastern edges of the Atlantic and eastern Pacific, and can lead to easterly flows to the UK.

Diffluent Block

A split in the eastwards flow can lead to a Diffluent Block. Examples with a closed high centre to the north of a closed low centre in the south are more likely to last for a prolonged period of time.

Last updated:

Follow us on

Creative Tote Flox lady Natural Bag avocado Crazy w0qXxEp0
  • RSS
  • Roxy Red Soft Ladies Jacket Shell SOL'S 8x1qU5

    Contact us

    Jacket Black Schwarz Women's Urban Satin Classic Bomber Ladies Black 7 0qxYXB

    Translate

      由 翻译强力驱动
    More information about our translations
    © Crown Copyright 2018
    Winter with Length Hood Red Padded in Transition Parka Jacket Lined C Black Jacket Mid Jacket Coat Ladies amp;ODD Black Women's Fleece Padded Navy Even Lightly wqxaBA1

    Green Beach Help to It Tote Gym x38cm Bottle Bag a Little HippoWarehouse Shape 42cm Minds Takes Heart Big Shopping 10 litres wF1RgqgA