Jet Streams – a river in the sky

A big temperature contrast across America has led to a powerful jet stream driving low pressure systems towards the UK over the coming days, as shown in this short video.

So what is a jet stream?

Over the Earth’s surface there are large-scale wind circulations. The global circulation can be described as the world wide system of winds by which the necessary transport of heat from tropical to polar latitudes is accomplished. In each hemisphere there are three cells (Hadley Cell, Ferrel Cell and Polar Cell) in which air circulates through the entire depth of the troposphere. Continue reading

How to interpret a weather radar

When making decisions on the weather, one of the key tools available to meteorologists, aviators, and the aviation industry in general is the weather radar.  There is a good network of radars that cover the UK and Ireland.  Lets take a look at how to interpret this radar imagery.

Showers

This radar image shows a day with heavy showers and thunderstorms.  Showers and thunderstorm form small “blobs” on the radar image with the higher intensity precipitation showing in the centre of the blob.  Clusters or lines of heavy showers/thunderstorms can also develop in certain weather situations.

radar-showers

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