High pressure is dominating the UK at the moment bringing a lot of settled, dry but at times cloudy weather. Sudden Stratospheric Warming is taking place high up in the Polar Stratosphere, what does this mean for the weather going forward?
Firstly, we’ll discuss what the EC46 model is showing. For week 1/2 it keeps high pressure across the UK so I think this weekend and certainly into next week will see a lot of dry, calm weather across the UK.
As we move towards the middle of January the model begins replacing high pressure with low pressure, so perhaps turning a little more unsettled towards the middle of January with periods of wet and possibly windy weather.
As we head towards the end of January and into early February the model develops high pressure Northwards towards Greenland and with low pressure to the East, this sets the scene for quite a cold period of weather across the UK.
However. There is a caveat in the mix for January.
Sudden Stratospheric Warming
The Stratosphere above the Arctic is rapidly warming and models are predicting that the Polar Vortex will split, when this happens a kind of “re-shuffle” across the Northern Hemisphere happens.
Normal models like the one talked about above become far more unreliable than they usually would be. As this “split” propagates downwards through the Stratosphere eventually reaching the Troposphere where our weather occurs, it can have vast changes to weather patterns.
Because of the current on-going Sudden Stratospheric Warming, longer range forecasts are effectively impossible. We don’t know what effect the warming will have on the weather patterns or when this will occur.
For that reason, models like the EC46, GFS, ECM are prone to wild swings between outputs. We could see a “Quick Trop Response” in that high latitude blocking develops quickly and we see cold air flooding Southwards out of the Arctic into the mid-latitudes, or it could take a couple of weeks before we see any impact (if any).
Lots of uncertainty going forward. Our advice is don’t pay too much attention to the model outputs beyond days 5/6 – We’ve got a period of high model volatility coming our way.
We’ll be sure to bring you reliable updates when we can.