The jet stream this week is very fierce, and is pulling down unusually cold westerly winds which is increasing the risk of snow showers both tomorrow (Tuesday) and on Wednesday. It’s the gradient of temperature, the cold Arctic air mass over and to the north of the UK and the relatively warm tropical air mass to our south that’s creating such a steep pressure gradient and the risk of very powerful wind gusts in the projected storm on Wednesday night, cold air in place will mean there’s a significant risk of snow for northern parts of the country, which could be quite heavy.
The nature of storms (their unpredictable streak), means tweaks further north or south in the projected path of the storm in the coming days are likely, therefore the forecast/ areas likely to get heavy snow/ severe winds are “uncertain”, as of yet. However at the moment more central parts of the UK (Southern Scotland, Wales, Ireland, Northern England & Midlands), are slightly more favored for the worst of the weather, but that could change.
The jet stream passing over the surface areas of low pressure at 250mph is enough to rapidly intensify any storm systems caught up in the jet stream. The below image shows the strength of the jet stream which is fueling the storm system.
Two real severe weather risks on Wednesday night are severe gale force winds and heavy snow. Very latest output, which uses the most up to date meteorological input is suggesting a period of heavy snow across Northern England, Northern Ireland and Southern Scotland. The heavy winds slightly further south, into central Ireland, Wales the Midlands with 70-80mph gusts and much of Southern England with 60-70mph gusts. The potential is there for a very disruptive overnight spell of weather, with the strong winds projected during the Thursday AM rush hour across eastern England, with lying snow covering more northern regions.
Tweaks southwards have been taking place in the projected output for the storm in the last 24 hours, meaning further adjustments south of the suggested areas are possible.
As the time of interest is still a couple of days away, changes are still very much likely. Stay tuned for frequent updates.
There’s still some severe weather to put up with over the next few hours. Strong winds will push in heavy wintry showers, some leading to accumulating snow to lower levels, where some minor disruption is likely. Over high ground however snow will be more significant, with 10cm+ in many areas.
There will also be a lot of instability in the atmosphere, meaning some lightning and thunder is possible. Although most central and southern areas will miss out on any snow, some wet snow is possible in heavier bursts. There’s a risk of drifting and blizzards on high ground in the north, particularly across Scotland and Northern Ireland, as well as Pennine regions.