Good afternoon and welcome to our long range forecast. This is posted either once or twice a week covering from 4 days ahead to 10 days ahead. In this update covering from Thursday 17th June until Saturday 26th June
Please note there is not a lot of accuracy for this kind of time frame. Anything beyond 4/5 days out becomes really difficult and subject to change so we will be looking at trends. Mainly take with a large vat of salt. We will be using the main two computer models for this. The ECMWF ( European Centre for medium range weather forecasts) which is based in Reading and the GFS (Global forecasting system) which is the American based global model.
This comes from the GFS 06z run and ECMWF 00Z run. I will refer to EC to save on typing.
Thursday 17th June
Some slight model differences for next Monday. The EC has high pressure again across the bulk of the UK with rain and scattered showers across the Western Isles with sunshine and cloud. Brisk winds. Rain and thundery showers across the bulk of the UK. The GFS builds in high pressure across the Western isles with fine dry conditions with sunshine and cloud. With lighter winds. Rain across large parts of the UK with thundery showers.
Friday 18th June
The EC keeps high pressure across the North of the UK with low pressure forming in the North sea bringing rain and thundery showers across parts of England and Wales. For us in the Western Isles it would be fine and dry with sunshine and cloud. A few scattered showers. The GFS has high pressure across the Western Isles with plenty of sunshine and feeling warm light winds. Rain and thundery showers for large parts of England and Wales.
Saturday 19th June
Some model differences for next Saturday. The EC has low pressure both in the Atlantic and the North Sea bringing rain and showers to the UK but for us in the Western Isles it will be mainly fine and dry with sunshine and cloud with a few scattered showers. The GFS keeps high pressure in charge across the Western Isles with decent and prolonged sunshine and brisk winds. Rain and showers across large parts of the UK.
Sunday 20th June
More model differences for next Sunday. The EC has low pressure across the UK with rain and showers and these will move across the Western isles and be accompanied by brisk winds. The GFS has high pressure across most of the UK with rain and showers across the Western Isles. An area of low pressure moves to the West of the UK but for most it will be a dry and sunny day.
Monday 21st June
Some good model agreement for next Monday. Both models are suggesting low pressure dominating the weather across the UK. The EC moves the low pressure system northwards across the UK and this would bring rain and blustery winds and this would move across the Western Isles later in the day. The GFS suggests a fine and dry start to the day for the Western isles with an area of low pressure moving across ireland and bringing rain and showers into the Western Isles later in the day. Brisk winds.
Tuesday 22nd June
Some model disagreements for next Tuesday. Firstly the EC the area of low pressure mentioned above moves into the North sea and it would bring spells of rain across the Western Isles which would be heavy at times. Along with brisk winds. The GFS on the other hand moves the area of low pressure southwards so after some morning rain it would become fine and dry with sunshine and cloud. Winds would also ease.
23rd, 24th, 25th and 26th June
Now this is the really long range. So take it with a large amount of salt and is the silly range. So the GFS is suggesting that things become a lot more settled with fine and dry weather with sunshine and cloud.
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