I have been watching the temperatures in the Polar Vortex. The polar vortex is nothing new and it’s always there, 10hpa is 30 km and 1hpa 45 km. So you can see its very high above the surface of the Earth.
The polar vortex appears each winter, it forms during the late Autumn and strengthens during the winter when there is no solar heating in polar regions, strengthens during winter, and then breaks down as sunlight returns to the polar regions in spring.
Now some winter’s we can have a Sudden Stratospheric Warming (SSW) this is when the temperature of the Polar Vortex suddenly warms and splits the Vortex or causes a displacement. Now if this happens this can cause a wind reversal from westerlies to easterlies and this can cause a harsh winter. This happened winter 2012/13 and we ended up having very cold extended period of snow and cold temperatures.
Now if the Vortex does suffer the effect of a SSW and splits there is still no guarantee we would have a harsh winter, only 1 in 4 events does bring a harsh winter to the UK, but saying this it is a possibility. So over the coming day’s and weeks I will be watching to see if the temperature increase in the Vortex and it splits or a displacement takes place .
It is a long process and we are looking towards the 1st week of December before we will know if the SSW has happened and the Vortex has split or displaced. It then takes around 14-21 day’s after that event before the cold air moves down from the top of the Vortex into the Troposphere. So lets just wait and see if it gets interesting towards the end of December.
I have added a set of images from the Vortex showing the temperature at 10 hpa 30 km now and the temperature forecast for 4th December.
The next set of images are for the very top of the polar Vortex at 45km now and for the 4th December.
You can see it’s forecasted to get toasty in the Vortex. So lets wait and see and I will keep you well updated on this subject.
But please the cold nights we are going to have over the next few nights have nothing to do with what you have just read.
I am sure the tabloid will be full of the word Polar Vortex.