It does not indicate north east south west, it tellls you what direction the wind is blowing, it is not a fixed item, it rotates with the the wind, if the wind is blowing to the east the weather vane will point that way.
Don't forget, Janet, that weather-vanes originated in the days when people really did know about weather-patterns...people such as farm-labourers, fishermen etc all needed that knowledge. Nowadays, we are nearly all sheltered from the worst the weather can do to us and pay little attention to weather details....
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Still, we know that winds from the north-east are often wild and cold whereas those from the south-west are mild and often wet. Generally, the south is milder and warmer than the north, so the south wind affecting your area today quite probably means that temperatures may rise for you. Alternatively, you could pop along to the nearest farm and ask what the ploughman thinks is going to happen! He'll still know.
Well thank you for that, I have noted what you have said and will monitor the weather and the weather vane now to see if it works. Spoke to the farmer yesterday as it happens since we live right opposite and all he says is lotsof rude words about global warming and not enough rain to make the grass grow for the cattle to graze and there was i enjoying the lovely sunshine