Easterly gales vs South Westerly's.

[ianc1200]

After the drama yesterday, where I spent most of the day tying & weighing down the storage tents over my boats, seeing the footage from Swansea Marina & a harbour in Cornwall, we'd have had a lot more damage in the same strength, but easterly winds. I've only been boating on the east coast a few years, and it's my first winter living here, but have we had 100+ mph winds from the east in living memory? Or is there some reason why SW gales are so much stronger?

 

[ex-Gladys]

You need to understand the science behind mid-latitude weather. Weather is driven by heat. Over the oceans the air masses heat up more effectively, because water retains heat much more than land. So where the low forms, the heat energy heats the air and causes it to rise, and for various reasons the air starts to rotate (anti clockwise in the Northern Hemisphere) and because of the Coriolis effect appears to move to the east as well. Obviously to the west of the UK we have a huge expanse of Atlantic Ocean. To the East, we have a huge Expanse of Europe (the land is cold and can't heat the air much)…. Hence the storms come from the Atlantic.

We DO get weather from the East, but it's very different. In these circumstances we usually get a large "blocking " high forming over the North Sea or Europe. This high will rotate clockwise in the N hemisphere, so the air is travelling down from the north (as in Arctic) and over the cold land mass. The high stops the Atlantic weather systems (by making them divert north), but as they get to the large cold high they dump all their acquired moisture as snow over the UK. Remember the Beast from the East? Blocking High over Europe.

 

[LittleSister]

As I understand it -

We in the UK are on the general boundary between a band (round the world) of warmer air to the south and another of colder air to the north. Depressions develop and track eastwards along that (somewhat mobile) boundary, developing the typical inverted wedge shaped wave of warm 'southern' air projecting into the colder north with warm front ahead and cold front behind. The centres of most of the serious depressions pass to the north of us (at least in southern Britain), so we get not only the 'pressure' wind circling the depression anti-clockwise (because we're in northern hemisphere), but also the intensifications along the fronts, especially the cold fronts, as they pass over us. Thus, when we ar most likely to get gales - deep depression, fronts passing through, the wind is most likely to be in the W or SW sector.

That.s also in the context of wind from roughly the SW is the most frequent here.

We certainly can get gales from the East, but they tend to be far fewer, and also (but not necessarily) less severe.

 

[johnalison]

The weather here is very different to that in the SW. I can remember from my childhood holidays the pleasure I got from watching waves breaking over the harbour wall in Mevagissey during SE gales, often the highlight of the holiday. Recent cruises in the area also surprised me with the frequency of SE winds, which in the E Coast SE winds seldom seem to last long and are often a pleasant warm break before it turns SW and rains. Other will know better, but NE gales don’t seem to get above F7-8, if that.