I can only speak for this area as you are going to get local variations as always when it comes to the weather but looking at the figures for Manchester Ringway, Woodford, my observations and feelings, the number of days with thunder have definitely declined in the last few years especially since and including 2010.

The figures I have
1981: 12
1982: 15
1983: 21
1984: 19
1985: 7
1986: 7
1987:13
1988: 14
1989: 6
1990: 21
1991: 15
1992: 20
1993: 14
1994: 21
1995: 17
1996: 12
1997: 13
1998: 17
1999: 23
2000: 17
2001: 12
2002: 10
2003: 4
2004: 17
2005: 5
2006: 12
2007: 9
2008: 10
2009: 8
2010: 2
2011: 3
2012: 8

2013 was a better year, even had thunder snow that year, last year was very poor and this year, no thunder at all the far.
The 1990s were brilliant for thunder which confirms my recollections of that decade. 1992 and 1994 have stuck in my mind for thunder. 1999 was another good year for thunder.

The figures suggest to me that thundery plumes coming up from the south affecting this area has declined since the start of the 21st century and markedly since 2010. Also showery airstreams with a westerly component especially the NWly are infrequently producing the classic shower passing through with a single crack of thunder.
Unless the rest of the years of the 2010s change drastically and this year is showing no change thus far, the 2010s are looking a very thunderless decade here overall.

Very interesting. I lived in Longsight during this period and can recall a lot of thunderstorms during both summers in particular. Remember one particular one that developed over the Pennines late in the afternoon that continued well into the night giving some spectacular lightning displays.

I can't be sure but it feels to me as if everything has been slightly shunted further east in recent years. Plumes and associated thunderstorms seem increasingly restricted to the far SE. Even here in Kent there seems to be a deficit compared with earlier years.

How many times in recent years have we seen an MCS explode to live in NE France sheered NE'wards towards the Low Countries ? A fair few times IMO.

We did very well for thunder over the winter with the repeating North Westerly airstreams. I lost count of the number of heavy hail (sometimes snow) showers each giving 1 or 2 cracks of thunder as they quickly bumped into the Pennines.

The overnight storm last July was incredible in terms of length and the vivid lightning.

Not sure on how this summer will go but I have a feeling any wafts of hot air will be quickly swept away limiting storms to Southern and Eastern areas.

In penrith the average number of thunderstorms per year has gone from zero to zero so no change then!

However, I see loads of thunderstorms during my frequent trips to Corfu, the thunderstorm capital of Europe.

Andy

FWIW, here's my local thunder day tally for the last 5-6 years:

2009: 12

2010: 6

2011: 6

2012: 8

2013: 6

2014: 17

2015 (so far): 4

Generally pretty poor for my area in recent years, although 2014 was pretty awesome. Certainly feels like a decline from the 1980s/90s.

According to the metoffice...

Annually 8-12 days where thunder is heard in the Manchester area between 1971-2000.

http://www.metoffice.gov.uk/public/weather/climate/#?region=uk

Thunder what does that sound like and lightning was does it look like!!!

Last year was good with thunder in every month except December.

3 days so far this year

Previous years were more of a struggle.

We get a fair chunk of thunder in autumn thanks to the warm English Channel

19 days with thunder heard here last year - even had a rumble from a hail shower at 8.45am on Xmas day - well rare! This year has been extremely quiet so far - only distant rumbles heard from the SE on March 1st - Stoke recorded thunder-snow around 5-6pm on that day according to my records

We only had three days with any thunder in my location throughout the whole of 2014 to my recollection, two of which came in December. Only August 14th saw any thunder here during last summer. We haven't had any here at all in 2015 thus far.

Not that I'm complaining though- I can't stand thunderstorms! They've never been my idea of entertainment if I'm being honest, and that's been my view of them ever since I was a kid.