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Autumn storms

Autumn storms

This week, after months of drought, it finally rained. Of course it rained! It was perfect timing. I had finally got fed up with living with the coating of mud that the clouds had dumped a few months ago and covered all the terraces around my house. I got up super early and spent hours and hours scrubbing and mopping the tiles with detergent until they were gleaming and clean. Naturally, it had to rain and cover everything with mud again! Luckily, they were much easier to clean the second time around.

The other night, the storm swept quickly over the mountainside where I live, entertaining us with a fantastic show of thunder and lightning and giving the plants a nice soaking for half an hour or so. We even stood outside getting wet and stared up happily into the sky until the raindrops got too big and the lightning got too close for comfort.

I wonder if this little storm has lowered the temperatures enough to save us from what is known as the ‘gota fría’… the dreaded ‘cold drop’, which sometimes occurs in the western Mediterranean during the autumn. I have experienced a few of these and, I can tell you, it is the number one reason for keeping your roof in perfect condition.

In Spain, a meteorological phenomenon appears when a front of very cold polar air, a jet stream, advances slowly over Western Europe. If a sudden cut off in the stream takes place, caused by several reasons, such as the effect of high pressure, a pocket of cold air detaches from the main jet stream, penetrating to the south over the Pyrenees into the warm air in Spain, causing its most dramatic effects in the Southeast of Spain, particularly along the Spanish Mediterranean coast, especially Valencian Community where I live.

This phenomenon causes extremely violent downpours and storms, with speeds of 100–200 km (60–120 mi)/hour. When the high atmospheric torrential rain causes instability in the lower air layers to combine with a significant amount of water vapours, the combination causes the masses of cold air to rapidly discharge up to 500 litres per square metre in extremely rapid rain episodes. This phenomenon usually lasts a very short time, (from a few hours to four or five days) as it exhausts its water reserves without receiving a new supply.

This is enough to cause significant damage to an area which receives almost no rainfall. Although my house is well-maintained, sometimes as the storm drags the water has found its way through the roof tiles and poured through the ceilings and around the window frames.

I can only hope that the rain we have already experienced has lowered the temperature enough to save us from a 2015 battering from our most extreme storm.

Juliet Allaway

 

Written by editor