Cold Snap Behind RinaAdded : Thursday at 11:02 Worth a little look at this cold snap which approaches this weekend from the GFS ► perspective. The main scenario is that we have the remnants of Rina which swing Southeast during the course of Friday night and overnight into Saturday. It's only really after that when the colder air floods in from the North.
This is the chart for Friday :-
There is remnants of Rina. By Saturday morning she is Southeast of the UK :-
Just a trough with some moderate rain and strong winds, but all perfectly normal for November. It's the 36-48 hour period behind this though where things get a little interesting.
If you take a look at the freezing level charts :-
An impressive vortex across Norway and high pressure building across Greenland. This effectively squeezes a shot of colder air South during Saturday and Sunday.
Sadly, we need to add a sense of realism to this as gone are the days when meteorologists highlighted uncertainty and probability which was adhered to. But Northerlies are dry... cold but DRY. In these scenarios it's the usual areas which see the snow as they have the mixture of moisture and temperature and they are Northern facing coasts of Scotland and Northern Ireland with perhaps some hail/graupel thrown in across Northeast and Eastern coastal areas.
One thing though which has appeared in the 6z GFS ► and was also in the overnight GEM run was a rogue trough which runs in from the North. You can see it here on Sunday across Central areas :-
At the moment we aren't buying too far into this feature as global models tend to have too much forcing in Northerlies and are sort of "itchy" to develop short wave troughs which never happen. But, it's still something worth keeping an eye on over the next few days as if it does occur then the risk of snow for higher ground of England and Wales is possible, but more likely is that it falls as sleet/rain and then freezes overnight on Monday morning which is something which we have mentioned in the Weather Watch.
So, as usual, it's a rather messy and clumsy Northerly and for many it will feel a little more like November which you are used to in the area which you live in.
METEOROLOGIST : MARSH |