13 Jul 2012

Signs of the jet stream edging north. Brighter and warmer for the Olympics?

Having delivered nothing but tales of rain and flooding for the past few months, I’ve been looking forward to this day. I can finally see a possible end in sight to the continual deluge of very wet weather that’s been with us since April.

You’ve heard me talking about the jet stream a lot during recent months and how its position influences the weather that we experience.

Normally during the summer months, the jet stream generally sits to the north of the UK which steers wind and rain bearing areas of low pressure towards Iceland and Scandinavia.

However, so far this summer, the jet stream has been sitting to the south of the UK, with a conveyor belt of low pressure systems being thrust towards our shores bringing unseasonable and record-breaking amounts of rain.

Although not a summer month, April was the wettest on record. This was followed by a cool and wet start to May, with the wettest June on record thereafter. If that wasn’t enough, the beginning of July has been very wet as well.

With the ground sodden and little or no capacity to absorb any more water, flooding has been a serious issue. Each time it rains heavily, the risk of flooding increases very quickly as full rivers struggle to cope with even more water.

Each day, as well as looking at the weather forecast for the next five days, I also take a look at the general trend for the next few weeks.

Earlier this week, there were hints that the jet stream would head further north towards the end of the month. At first, I was doubtful as it had suggested the same a few weeks ago for early July – and, as we know, that certainly didn’t come to fruition.

However, for a few days in a row now a number of different weather computer models have been suggesting a trend for the average position of jet stream to drift northwards during the next two weeks.

It’ll be a gradual process, so don’t expect to open the curtains tomorrow and be greeted with blue skies and a heat wave.

What you will notice though during the next two weeks is that unsettled weather will tend to become increasingly confined to north western parts of the UK – Scotland, Northern Ireland and north west England.

Position of jet stream (solid area of blue) on 13th July to the south of the UK.

Forecast position of jet stream (solid area of blue) on 22nd July to the north of the UK.

Elsewhere, whilst there’ll still be some showers or the odd rainy day, it’ll be drier than of late with more in the way of sunshine.

Temperatures are likely to be higher with a trend towards the range of 19-25C – especially across England and Wales.

So, the start of the Olympics may not be a washout after all. But before you get too excited, there is one caveat that you need to take away with you. This is still two weeks away and things can change, so stay up to date by bookmarking my blog or following me on Twitter – @liamdutton

Jet stream images courtesy of NOAA

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