With a very deep low, chilly uppers and warm SSTs I expect there will be a decent amount of thundery activity in the NW next week as the showers pack in. I bet some will even see some thundersnow. Possibly extending further south later as well. We've had some decent thunderstorms here in December/January over the past few years from a similar setup and even thundersnow in December 2011 and in January 2013.

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Yesterday evening, there was a thunderstorm that almost grazed the NE coast of East Anglia; heard several rumbles in Lowestoft.

Thunder and lightning with snow between 5.30 and 6.00 am this morning. 

A loud rumble from a hail shower around 8.45am, further heavy showers followed. No info from E. Cheshire after 10am, as we had a drive to S. Leicester - the showers died out after Stoke, but signs of earlier showers all the way to N. Leics. in the form of wet roads, spray and puddles! Still some showers around from Stoke northwestwards earlier this evening on the way back to Congleton! Pressure between 1026 - 1027mb .. academic when there's an unstable, moist flow in from the Irish Sea moving through the Cheshire Gap! 

A fair few lightning flashes around the Straits of Dover this afternoon and evening I've noticed from, http://www.weathercast.co.uk/radar/archive-for-netherlands.html (just zoom out to see the lightnings).