Understanding the regional mountain weather forecasts is my second step in researching the weather to help plan my days out. This follows on from Step One, understanding the national forecast, which I wrote about last month.
How I access this information depends on whether I am working from a desktop computer or a smartphone. If I am on a desktop then I tend to go direct to specific websites. On my smartphone, I use the MWUK app to act as my one-stop-shop.
Mountain Weather Information Service (MWIS)
My first resource is the Mountain Weather Information Service (MWIS) forecast. This used to be the only accessible weather forecast tailored to the UK mountains. However, this is no longer the case.
MWIS regional mountain weather forecasts cover pre-defined mountain areas of the UK at a regional level. MWIS currently covers 10 regions, including, for example, Snowdonia, the Lake District and the West Highlands.
The MWIS forecast does have a drawback, in that they only publish it once a day in the late afternoon. By the time you set off in the morning, you are going somewhere based on a forecast from 18 hours ago. There are other resources available which update more frequently.
However, MWIS still has a number of strengths based on its original philosophy and ethos. MWIS forecasts have always been ‘impact-focused’. This means that the focus is on the effect of the weather on you, the mountain-goer. For example, they do not only state that the wind speed will be 30mph. They go on to say that the effect of this on you is that “ease of walking will be impeded”. Next, MWIS have always tried to use terminology that is accessible and understandable to most people.
Each forecast covers aspects which are important in the mountains. These include:- wind speed and direction; precipitation (rain/snow); cloud and visibility; sunshine; and temperature.
As a result, MWIS’s forecasts are easy to understand at a glance. They help create an overall picture of the conditions that you are likely to experience as a mountain walker or climber.
Met Office Mountain Forecasts
After the MWIS forecast, I then move on to the Met Office’s mountain forecasts. I do this for two reasons. First, it’s good to see if it is similar or very different from the MWIS forecast. If it is very similar, then the weather is probably behaving predictably and that both forecasts will be right. If it is very different, then the weather is probably behaving erratically and neither forecaster is 100% confident. In this case, I tend to plan on the basis of what the most pessimistic forecast has said.
Like MWIS, the Met Office mountain weather forecasts are based on covering 10 mountain regions. However, in addition to forecasting in the afternoon before 6pm, they also update these at 6am the next day. This means you can do an early morning check based on the latest information, which could alter your plans significantly.
The advantage of the Met Office mountain forecast over MWIS is that it includes more detail. It starts off with a general narrative similar to MWIS. But in addition it has tables of data showing the conditions in 3-hour blocks during the day (eg at 0900, 1200 and 1500) and at different altitudes in 300m blocks (eg 0m, 300m, 600m, 900m etc).
This helps me improve my understanding of what conditions I am likely to experience throughout my day. For example, at 0900 I might be planning to be around 300m above sea-level. By 1200 I might be at 900-1000m. Finally by 1500 I should be descending and might be around 600m. I can therefore draw some conclusions about the conditions I might experience during my own planned day out.
In winter, one critical piece of information is about freezing-level. Where is it at the start, middle and end of the day? What does this mean for my day out?
If I am working from my smartphone then I follow a similar line of thought.
The MWUK app includes a direct link to the MWIS forecasts, so I use this first.
Then I tend to use the MWUK app’s own regional forecasts to access the more detailed information. This provides forecasts for 16 regions in England, Wales and Scotland and a further 3 in Northern Ireland.
Each regional forecast starts with a section that is similar in format to MWIS’s offering. But it then includes a section more like the Met Office, with 3 hour time blocks. In each time block, you can drill in further to see the conditions at different altitudes.
Scottish Avalanche Information Service (SAIS)
Finally, in winter, I will of course also be looking at the regional avalanche forecasts. These are provided by the Scottish Avalanche Information Service (SAIS).
This can be accessed directly or, again, through the MWUK app.
SAIS provide forecasts of the avalanche conditions for 6 different mountain regions of Scotland.
I will start by reading the page on the ‘Observed Avalanche Hazard’. This is what the forecasting staff observed and tested on their field visit ‘today’. They do this every day during the winter months. Next I look at at the ‘Avalanche Hazard Forecast’. This is where they link their observations to the weather forecast for ‘tomorrow’ and deduce what the avalanche hazard is likely to be.
Planning Decisions from Regional Mountain Weather Forecasts
The decisions that I make as a result of looking at these forecasts fall into two main categories.
First, the regional forecasts (including the avalanche forecast) will help me to choose which region to visit. For example, it helps me to understand that the winter climbing conditions may be better and safer in the west (or east) side of Scotland than on the opposite side.
Second, I will now have a very clear picture of the likely conditions throughout the day and at different altitudes. This helps me decide if I should go for the summits or stay low seeking shelter from the wind.
- Having checked the overall national weather forecast, next I turn to regional mountain weather forecasts.
- I mostly use a combination of direct websites and the MWUK app.
- My first stop is the MWIS regional forecast for a general overview.
- Next, I look at the Met Office or MWUK app for more detailed data by time and by altitude.
- If it is winter and I am in Scotland, then I also look at the relevant avalanche forecasts.
- Armed with this information, I can choose which region I should visit (if I have a choice) and what my general plan for the day might be (go high or stay low).