The “Omega Siege” guarantees bright spring weather, but what exactly is it? A knife that cuts both ways.

What is an omega blockade?

Denhau: “This is a large high pressure area, both at a height of kilometers and on the ground, and it does not change its position much. On the elevation maps you can recognize the Greek letter omega (Ω), hence the name. You should know that the air pressure is about 1013 hectopascals. Anything above is usually categorized as high pressure, and anything below that as low pressure.

“With an omega block, you see an exceptionally high pressure. A pressure of 1038 to 1040 hPa is expected in the coming days. It takes a while to get back to a pressure of 1.013 or less. It’s not like you’re losing 20 hPa a day. The higher that pressure, the longer it will last. high pressure area.

Then this high pressure zone ensures dry weather for a longer period of time. If it happens in winter, it is sometimes cloudy but dry. If you have such high pressure between March and September, you will get pleasant weather, with higher temperatures. ”

How long does an omega blockade usually take?

At least a week, but this may take longer. Sometimes it takes two or even three weeks.”

How exactly does this work?

“At higher pressure you have downward motions. That is, the pressure goes up because that air is compressed. Compare it to a bicycle pump: when you inflate your bike tire, the pump gets warm afterward, because you compressed the air.”

Where is that block?

“The real blockade of Omega is currently over Poland and Eastern Europe, where the air pressure is very high. This blockade has consequences for us: we get a supply of southern air and therefore warmer weather. ”

Are there differences between the regions in the middle or the edge of the omega block?

“We are between an Omega cluster and a series of low pressure areas over Ireland and the Atlantic Ocean. That’s why we have that southern sky. Since we’re on the brink, it remains less stable here.”

Is the weather vernal across Europe now?

“No. A region of high pressure in one place is offset by a region of low pressure in another. This is the equilibrium in the atmosphere. Where the omega mass is, you now have this dry weather. However, this also means that the areas of low pressure to the west and east It is also prohibited.This is the case now in the Balkans and Turkey.There now you have much more precipitation and chance of heavy thunderstorms or floods due to days of rain.There is even snow.

“It’s a double-edged blade: Being in such an area of ​​high pressure is great, but if you’re outside and you’ve been in wet weather for weeks, it can also cause problems.”

How extraordinary is such a blockade?

“We often have snags. I don’t follow the numbers, but they are common. If you look at the whole earth, you will always find a high pressure area somewhere that lasts for a week. Think of the dry periods in the summer of 2017 to 2020.”