Thread by @althecat

A series of images of a weekend burst of energy and water into the European weather system starting 8am on Saturday 17th.
2nd image: 3pm 17th - percussive impact as WMA water hits EU system over Aegean.
3rd image: 9.30am 18th - 5 separate weather systems. #EUClimateChange

The impact of an injection of rain bearing air from West Africa northwards on Europe weather is striking.

A low pressure system is forecast to develop over Western Russia. This displaces the ridge of high pressure which had briefly reversed the flow of cold arctic air south.

This happens almost immediately - and has an immediate catastrophic impact on anticipated European temperatures which are now set to plummet and stay low for a fortnight.

https://twitter.com/althecat/status/1384132226011389956

European @ECMWF model simulations run last week did not contain the burst of water coming up across Africa. (1st image), today's is actual weather pattern is strikingly similar, but for this. (2nd image). And this is why most Euro forecasts are now wrong.

This is the latest Euro @ECMWF model forecast for Europe. It shows the quantity of précipitable water in the air. Arctic air has none and is represented in the image as black & grey.

We can compare this from what was forecast by the Supercomputers just three days ago.

In this simulation we start in the same place (midnight this morning). It starts in a similar way - but the outcome is - as you see completely different. The rain clouds win and the cold dry air heads back north towards Russia.

For those of you who are interested here are the corresponding 16/4 and 19/4 @ECEMWF MLSP charts for Wednesday. Today's is on the left, and what was forecast on Thursday is on the right.

Here we see forecast European temperatures for Saturday 24th April (midnight [top] and midday [bottom])

[left] today's forecast.

vs

[right] what it had been expected to be as of 72 hours ago.

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