A Cold, Wet And Often Windy Week Ahead, Next Week Looks Potentially Worse

Written by Mark Vogan on April 26, 2015 in Rest of Europe, Spring 2015, United Kingdom & Ireland with 0 Comments

It’s was a clear, cold start to Sunday with rural frost around. I was out early and had to scrape the wind screen.

Credit: Mark Vogan

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Once the sun begins to warm the lower levels, we raise the lapse rate or temperature difference with height as colder air is back. Since yesterday’s post, a frontal zone has drifted south over the UK pulling down colder air from the north but that boundary could spell a damp start to the London marathon.

However, if exposed to the northerly breeze and out of the sun, it will feel distinctly March-like and with the larger lapse rate comes ‘convective showers’. Those showers (mainly in Scotland, Northern Ireland, N England) will be heavy, blustery and may contain hail or even sleet or wet snow. It’s that time of year when showers become heavier and more convective as the instability increases when cold air aloft is in place.

With a large low positioned to the north over the Norwegian Sea and a 1028 high to our west extending up into Greenland, our air source is arctic and it will be throughout this week. Daytime highs will range between 5-12C but factor in that stiff WNW wind and it feels colder. Snow will fall in the hills.

Through the first half of this week, our wet weather will come in as systems ride around the main low in the Norwegian Sea but as the week progresses, so that low drifts south making for increasing wet and windy conditions by Wednesday across a broader area of the UK, Ireland and indeed western mainland Europe.

In comes the cold once again and the return of -5 to -10C air at 850mb.

Credit: AccuWeather Pro

Here’s the very latest ECMWF surface charts for the upcoming week.

Credit: AccuWeather Pro

As you can see towards next weekend, the low drifts east but high pressure builds into the cold air left behind, this supports continued convective shower activity and sharp night frosts.

Week 2

It appears that we remain within the chilly air with systems pushing in from the Atlantic, however the model sees a major low around day 10. Will be keeping a close eye on this solution.