Is it really a spanish plume?

Distance travelled ~ 457'958'400 km: day 178

Today is set to be the hottest day in the UK so far for this year, surpassing yesterday's 30°C. It's not all sunshine however as thunderstorms, hail and possibly tornadoes have also been forecast for later today. But what's causing this combustible mixture of heat and storms?

The favourite explanation seems to be the evocatively named "Spanish plume". It's an event that occurs once or twice a year on average, but in recent years has been less frequent.

'Spanish Plume' is actually a rather catchy name for a complex meteorological phenomenon which leads to warm conditions and heavy showers or thunderstorms over parts of the UK and north-west Europe.

A classic Spanish plume consists of very warm air that pushes north from around the vicinity of Spain towards the British Isles. Not surprisingly, that hot Mediteranean air warms us up. But then this air mass meets with cooler Atlantic air coming from the West - the kind of air that normally affects the UK. The plume air is pushed up over the cooler Atlantic air, and this produces thunderstorms.

Because the Spanish plume can cover a large area the accompanying storms can give widespread, heavy rainfall, often accompanied by hail.

But are we seeing the key ingredients for a Spanish plume now? According to the Met Office we are not. What we have at the moment is a warm area across the east of the UK - not from the Mediteranean. This warm air is encountering a cold front pushing across from the West, bringing showery rain.

This is different from a Spanish Plume according to Dave Britton at the Met Office, because for a classic Spanish plume you need to have warm, dry air push up from the south. This acts as a lid on local showers because the air can't rise through the lid. Eventually the rising currents of air get strong enough to break through this lid, and by now they're violent enough to develop into thunderstorms.

So although great weather for fans at Wimbledon today with Andy Murray's win, it seems our current weather is not due to the Spanish plume at all. Maybe somebody should think of a catchy title for warm air from the East meeting a cold front from the West?

Fingers crossed the storms pick up later for those heading out on a chase. Leave a comment or send the 23 Degrees team your updates and photos for a possible story or feature.

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