Long range weather forecast for the Western Isles – 11th July 2021

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 15th July until Saturday 24th July.

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 15th July

Both the GFS and EC have high pressure across the UK. The EC has some light rain and drizzle to start the day with it clearing away as the day goes on with some decent and prolonged sunshine. Still plenty of cloud. Brisk winds with occasional scattered afternoon showers. The GFS also has high pressure in charge but develops an area of low pressure over Northern Scotland. A weak area of low pressure with some light rain moving into the Western Isles. Some sunshine and it will be breezy.

Friday 16th July

Again the EC and GFS have high pressure across the UK. A day of sunshine and cloud with mainly light winds. Some decent and prolonged sunshine. Some scattered light showers. Feeling warm.

Saturday 17th July

Little change for next Saturday high pressure is across the UK from both the EC and the GFS. The EC moves an area of low pressure to the West of Ireland. For us in the Western Isles again light winds with sunshine and cloud. Some decent and prolonged sunshine. Feeling warm again.

Sunday 18th July

Some slight model differences for next Sunday. The EC brings that area of low pressure into Ireland which would result in some heavy rain here and some showers moving into the Western Isles later in the day. High pressure remains in charge for much of the UK. The GFS has high pressure across the bulk of the UK with a few scattered showers drifting into the Western Isles later in the day in association with a broad area of low pressure to our far North West. Winds will be light.

Monday 19th July

Some further slight model differences for next Monday. Some overnight rain Sunday into Monday according to the EC with rain and showers moving across large parts of the UK. But fine dry and sunny across the Western isles with brisk winds. The GFS shows high pressure across the UK. A few scattered showers for us in the Western Isles with some decent and prolonged sunshine and becoming drier as the day goes on. Winds will be light.

Tuesday 20th July

Again some slight model differences the EC has low pressure in the North sea which would bring rain and showers across Northern Scotland but a few of these showers will push into the Western Isles with some decent spells of sunshine. The GFS has high pressure across the UK with light winds. Some decent and prolonged sunshine and variable amounts of cloud with light winds.

21st, 22nd, 23rd and 24th July

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 the Wednesday will be fine and dry. Low pressure bringing rain and showers for the Thursday. Friday and Saturday sunshine and showers with brisk winds.

Our featured photo is Luskentyre beautifully captured by Megan MacSween

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s