Welcome to our long range forecast for the Western Isles. This is our twice weekly update covering up to two ahead. We look at trends and patterns. Usually posted on a Thursday and Sunday.
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.
EC – Thursday 4th November to Tuesday 9th November
So the EC is suggesting that high pressure will build across the UK on the Thursday but for us in the Western isles rain and showers will move across the islands. Into the Friday high pressure slides away to the South and low pressure moves in from the North West. For us in the Western Isles, we will see a dry start but rain will move across the Western Isles becoming heavy and persistent with blustery winds. On to the Saturday and low pressure will move across the North of the UK it will bring heavy across the Western Isles with blustery winds. Becoming drier and brighter later in the day. Into the Sunday and we will see rain and showers across the Western isles before a deep area of low pressure sits out in the Atlantic and feeds in heavy rain across the islands. Into the Monday and low moves across the Western isles with gale force winds possibly severe at times. Rain and squally showers heavy at times. Tuesday low pressure moves across the UK but becoming drier and brighter for us in the Western isles.
GFS – Thursday 4th November to Saturday 14th November
So the GFS is showing high pressure dominating across the UK on Thursday with fine and dry weather for us across the Western isles. Winds will be light. Into the Friday and high pressure clears away and some rain and drizzle before low pressure brings in heavier rain later in the day. For the Saturday low pressure moved across the Western Isles bringing heavy rain to start rain and showers later with winds reaching gale force. Into the Sunday and high pressure builds across the UK it would be a fine dry and sunny day for us in the Western Isles with light winds. Moving on to the Monday and band of rain would move across the Western Isles bringing rain heavy at times. Into the Tuesday high pressure across the South of the UK but further bands of rain and blustery winds move across the Western isles. The final 4 days of the time period will see rain and showers at times for us in the Western Isles but as high pressure builds across from the far East conditions will become more settled.
Thanks for reading any feedback is welcome. Featured photo from Màiri Robertson Carrey of Scarista