Spring / Summer 2010

[William of Walworth]

I've just seen TWO's new summer forecast too.

Am I right in thinking that this, for June, is somewhat out of line from what many on here are starting to suggest for later this month?

--------------------

June

Temperature: Slightly above average

Precipitation: Slightly below average

A spell of rather warm and dry weather is expected to develop early on as high pressure builds across the country. This is likely to break with showers or longer spells of rain returning during the second week of the month. As well as turning less settled temperatures will also fall. Towards the middle of the month drier and warmer conditions may well begin to return.

The second half of the month is expected to bring a lot of fine and settled weather to southern parts in particular, although the north should also have fine weather at times. The settled conditions may well last for much of the second half of the month, possibly becoming very warm at times in the south. Overall temperatures should be above average during the entire period.

www.theweatheroutlook.com

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What are the thoughts of members here about the above?

Edited May 31, 2010 by William of Walworth

[AderynCoch]

Interesting stuff. I never realised the 1995 La Niña didn't develop until autumn.

weatheronline have released their latest summer forecast, and to say it's not good is an understatement! No one knows for sure what will entail etc. etc. but they're usually quite reliable.

I think the phrase which springs to mind right now involves biological waste and an electrical cooling appliance.

[Weather-history]

The Manchester Summer Index for 2010 starts today and its not a great start with it raining and lack of sun. Last summer it was 194 and the winter index for 2009-10 was 197 First time since 1978 that the summer had an index value lower than the following winter.

Taken from the September 1986 edition of Weather and continued and updated by myself, here's the Summer Index rating for Manchester since 1901.

The Summer Index is 10 x [(mean max of summer) +(total sunshine)/67 - (rain days/ 8 ]

1901 249 1902 195 1903 209 1904 212 1905 223 1906 214 1907 147

1908 220 1909 171 1910 190 1911 274 1912 156 1913 205 1914 222

1915 196 1916 188 1917 228 1918 200 1919 203 1920 174 1921 249

1922 178 1923 174 1924 158 1925 246 1926 227 1927 175 1928 197

1929 211 1930 199 1931 173 1932 223 1933 251 1934 238 1935 243

1936 190 1937 213 1938 177 1939 213 1940 238 1941 236 1942 214

1943 209 1944 200 1945 223 1946 170 1947 255 1948 176 1949 267

1950 216 1951 201 1952 198 1953 193 1954 143 1955 277 1956 155

1957 216 1958 184 1959 269 1960 217 1961 203 1962 197 1963 194

1964 197 1965 189 1966 192 1967 223 1968 215 1969 234 1970 235

1971 205 1972 185 1973 234 1974 199 1975 268 1976 301 1977 223

1978 173 1979 199 1980 173 1981 196 1982 203 1983 278 1984 271

1985 180 1986 189 1987 169 1988 191 1989 262 1990 229 1991 207

1992 222 1993 194 1994 240 1995 298 1996 245 1997 232 1998 192

1999 234 2000 198 2001 211 2002 200 2003 247 2004 197 2005 224

2006 246 2007 174 2008 168 2009 194

Edited June 1, 2010 by Mr_Data

[kold weather]

Interesting stuff. I never realised the 1995 La Niña didn't develop until autumn.

weatheronline have released their latest summer forecast, and to say it's not good is an understatement! No one knows for sure what will entail etc. etc. but they're usually quite reliable.

I think the phrase which springs to mind right now involves biological waste and an electrical cooling appliance.

Yeah 1995's evolution towards a weak La Nina didn't really start till September, and even then it was a borderline event, only marginally cooler then what we saw in 2005-2006 which offically was only cool neutral and about as strong as the weak la nina of late 2000-01

[Kentish Kiwi]

The Manchester Summer Index for 2010 starts today and its not a great start with it raining and lack of sun. Last summer it was 194 and the winter index for 2009-10 was 197 First time since 1978 that the summer had an index value lower than the following winter.

Taken from the September 1986 edition of Weather and continued and updated by myself, here's the Summer Index rating for Manchester since 1901.

The Summer Index is 10 x [(mean max of summer) +(total sunshine)/67 - (rain days/ 8 ]

1901 249

1947 255

1955 277

1975 268

1976 301

1983 278

1984 271

1989 262

1995 298

2003 247

2006 246

Would it be fair to say then, if this index is a reasonably accurate representation of the summer as a whole across the UK, that 1976 was the best summer in the UK over the past century at least, with 1995 a close runner-up? And that 2003/2006 weren't as incredible in terms of the whole summer as some seem to make them out as, instead being more notable for intense, severe spells of summer heat over a less drawn out period of time, given they are the two lowest of the top 11 I've picked out, yet famous for record breaking heat-waves?

Edited June 1, 2010 by Kentish Kiwi

[summer blizzard]

Would it be fair to say then, if this index is a reasonably accurate representation of the summer as a whole across the UK, that 1976 was the best summer in the UK over the past century at least, with 1995 a close runner-up? And that 2003/2006 weren't as incredible in terms of the whole summer as some seem to make them out as, instead being more notable for intense, severe spells of summer heat over a less drawn out period of time, given they are the two lowest of the top 11 I've picked out, yet famous for record breaking heat-waves?

Other than the early August heatwave i would veiw 2003 as above average, but nothing special, however August 2006 was actually 0.1C below average making it remarkable that most of the 247 points would have been ammased during the first half of summer.

[Kentish Kiwi]

Other than the early August heatwave i would veiw 2003 as above average, but nothing special, however August 2006 was actually 0.1C below average making it remarkable that most of the 247 points would have been ammased during the first half of summer.

Ah thanks, as I thought then.

For some reason, although I may just be recalling incorrectly, I've seem to remember quite a few posts about the summers in the 1980's being cool, unsettled and generally dreadful, in line with the cold winters experienced that decade. Yet looking at the above index it seems 1980's had three stand-out summers in 1983, 84 and 89 while 1990's and 2000's only had one and two respectively, although 1995 was especially notable. Was it the case that through the ten years of the 80's the summers were very poor aside from those three, compared to continuous warmth through the 90's and to an extent 2000's? Or am I just remembering things wrongly...

[johnholmes]

Other than the early August heatwave i would veiw 2003 as above average, but nothing special, however August 2006 was actually 0.1C below average making it remarkable that most of the 247 points would have been ammased during the first half of summer.

being pedantic the first 2/3 of summer, June and July!

Ah thanks, as I thought then.

For some reason, although I may just be recalling incorrectly, I've seem to remember quite a few posts about the summers in the 1980's being cool, unsettled and generally dreadful, in line with the cold winters experienced that decade. Yet looking at the above index it seems 1980's had three stand-out summers in 1983, 84 and 89 while 1990's and 2000's only had one and two respectively, although 1995 was especially notable. Was it the case that through the ten years of the 80's the summers were very poor aside from those three, compared to continuous warmth through the 90's and to an extent 2000's? Or am I just remembering things wrongly...

remember that what Kevin is showing is for Manchester NOT the overall CET area. His figures, both summer and winter index's give a very indication of the overall weather I think but for Manchester so maybe a look at the CET data for those years may yield some information. Remember though the CET data is temperature only.

[Kentish Kiwi]

remember that what Kevin is showing is for Manchester NOT the overall CET area. His figures, both summer and winter index's give a very indication of the overall weather I think but for Manchester so maybe a look at the CET data for those years may yield some information. Remember though the CET data is temperature only.

Hmmm, yeah, I find the idea of an index which takes into account more than just temperature a much more useful indicator for the weather for the year. Is there any other index similar to that of Manchester, but for a more central or wider area?

Last year I suppose is an example of why using just the Manchester figures can be misleading for the UK as a whole, because I'm sure if you were to have one for London for instance it would have given a much higher summer index due to the prominent SE/NW spit through the summer.

[johnholmes]

adapt Kevin's system to your own weather data or the nearest staion with all the data required. In winter its simple enough but a lot of us have no sunshine recorder or a nearby site with one.

But as you say with several factors it does give a better 'feel' or idea of what summer or winter show.

[Summer of 95]

Other than the early August heatwave i would veiw 2003 as above average, but nothing special, however August 2006 was actually 0.1C below average making it remarkable that most of the 247 points would have been ammased during the first half of summer.

Surprising that 1992 got 222- that must have got 3/4 of those during June because July and particularly August were abysmal. And vice versa, the disappointing June in 1990 must have really held back that summer's score because August 1990 was definitely better than 2003 round here, and 1990 was certainly a better summer than 1999 which scores higher, did Manchester miss all the downpours in August 1999?

What stands out for me in that index though is that it shows just how bad summer 2008 was in western parts of Britain, despite certain people trying to convince us it was "average" or "typical"- by that index it was the worst for over 50 years! And 2009 rates no better than the often-cited-as-poor 1993.

[Thundery wintry showers]

Again bear in mind that Kevin's index refers to the Manchester area- the basis for those values is likely to be the stats for Ringway (Manchester Airport) and its subsequent replacement with Woodford in November 2004:

http://metoffice.gov.uk/climate/uk/stationdata/ringwaydata.txt

At Ringway, June 1990 was exceptionally cloudy and quite cool and wet. August 1990 was warm, assisted by the phenomenal heatwave at the beginning, but had close to average rainfall and slightly below average sunshine. Thus it doesn't surprise me at all that the index for Summer 1990 was relatively low. Conversely, the north fared rather better than the south in July & August 1992, with August managing near average sunshine at Ringway, and while it was cool and wet it was not exceptionally so.

As for 1999, while August was a dull month at Ringway with 6 days of thunder it doesn't stand out as being particularly cool or wet. The standout month is July 1999 which came out exceptionally warm and dry, and rather sunny, while June 1999 was slightly sunnier than average there.

One complicating factor is the way Woodford uses a Kipp-Zonen sunshine recorder whereas Ringway used a Campbell-Stokes recorder- the latter are known to overestimate sunshine by 10-15% during the summer half-year. This may lead to 2005-09 coming out with slightly depressed index values. However Summer 2008 was certainly not an average summer- exceptionally wet, and with many parts of the country having their dullest August since 1912.

At one stage I entertained thoughts of using the Met Office's UK-wide stats (freely available to the public here: http://www.metoffice.gov.uk/climate/uk/datasets/index.html#) to estimate what Kevin's index would give for the UK as a whole in summers going as far back as 1961. Not all of the relevant indices are available, but it is possible from what is provided to develop a rough approximation, so I may get around to that shortly.

[Eugene]

We have just had a below average Spring, like i said cold winters very rarely give way to warm Springs in the UK, i think the odds are in favour of a below average summer CET wise too.

The coming winter should be very interesting with a good base to start from, the past few winters have been excellent with some exceptional spells of cold weather.

[SP1986]

It would be fairly unusual for 3 cold winters in a row. I imagine this coming winter would have to really deliver to even come close to last years winter.

[BlueHedgehog074]

I think since we've had three wettish Summer's in a row (with the possible exception in the South-East last year that saw some good sunny periods), three cold Winter's could be possible I feel, though I do have a feeling that next Winter will be a touch milder with the Atlantic perhaps playing more of a role.

Looking ahead at June, the next two weeks could be quite mixed, with sunny spells, cloud, rain and potential for showers and thundery weather as Lower pressure makes attempts to settle over or near to the U.K.

[SNOW GO]

This Summer looks to me at the moment as a real mixed bag possibly with some thundery fireworks due to some humid conditions maybe? As for Winter 2010/11 early days yet I guess but I would go for again a cold winter prehaps not as severe in duration as 2009/10s BIG FREEZE but on a scale maybe of the 2008/9 winter that saw the large London snowfall in the early February of 2009.

[Milhouse]

Urrrgh, i cant think of anything worse at this time of year than bitter cold and snow. Thankfully the next few days couldnt be more different.

[William of Walworth]

Quite a lot of reluctance on this thread at the moment about making any kind of prediction beyond the next 7 to 10 days. Unsurprising really, given how knife edge current chat is on the Model Output Discussion thread as to whether warmer HP influenced conditions will or won't return in FI ...

[Thundery wintry showers]

The Met Office has stats for mean maximum temperature, sunshine totals and wet days. Thus it is possible to develop a summer index for the whole UK going back to 1961 using the same formula. The only caveat is that the original Manchester index might use a different definition of "rain days" (the MetO data only gives days >= 1.0mm).

1961 205

1962 201

1963 190

1964 204

1965 184

1966 196

1967 219

1968 208

1969 232

1970 222

1971 206

1972 199

1973 223

1974 201

1975 258

1976 287

1977 213

1978 187

1979 203

1980 179

1981 207

1982 210

1983 257

1984 251

1985 176

1986 202

1987 183

1988 191

1989 256

1990 228

1991 210

1992 210

1993 199

1994 226

1995 279

1996 238

1997 223

1998 191

1999 224

2000 215

2001 215

2002 202

2003 249

2004 211

2005 229

2006 259

2007 198

2008 198

2009 216

The 1961-2009 average index for the UK as a whole is 216- therefore 2009 was about par, taking all three main variables into account, but 2007 and 2008 were poor summers, sharing the 9th lowest value in the series.

Edited June 3, 2010 by Thundery wintry showers

[Charltonkerry]

Morning all, a slightly worried father of the bride, my daughter getting married in Maidstone on Saturday June 12th kick off 2pm (how can any body arrange a wedding when England are playing there first game in the world cup is simply beyond me, thats girls for you). I was wondering if it is possible yet for anyone to give me an indication of what the weather might be like, as we still got time to go out and buy umbrella's.

I didn't realise what a to do a wedding was, i was told all I had to do was pay or it, but you learn that daughters bend the truth sometimes. If this is in the wrong thread please feel free to move it.

Regards

Kerry

[summer blizzard]

http://www.esrl.noaa.gov/psd/data/correlation/qbo.data

The QBO value for May came in at -26, assuming this is not a record event this means that the QBO will peak no later than August, so still a chance we could see a nice August if it peaks this month or July and El Nino does'nt halt its decline.

One other thing to note in the longer term is that while there will be a moderate negative AO signiture present for the first half of summer we may get a stormy Autumn again, a weakening -QBO combined with a La Nina suggests the Polar Vortex running rampant in October/November.

MEI value for May was -0.5 as well, so El Nino is officially gone.

Edited June 7, 2010 by summer blizzard

[Summer of 95]

Again bear in mind that Kevin's index refers to the Manchester area- the basis for those values is likely to be the stats for Ringway (Manchester Airport) and its subsequent replacement with Woodford in November 2004:

http://metoffice.gov.uk/climate/uk/stationdata/ringwaydata.txt

At Ringway, June 1990 was exceptionally cloudy and quite cool and wet. August 1990 was warm, assisted by the phenomenal heatwave at the beginning, but had close to average rainfall and slightly below average sunshine. Thus it doesn't surprise me at all that the index for Summer 1990 was relatively low. Conversely, the north fared rather better than the south in July & August 1992, with August managing near average sunshine at Ringway, and while it was cool and wet it was not exceptionally so.

As for 1999, while August was a dull month at Ringway with 6 days of thunder it doesn't stand out as being particularly cool or wet. The standout month is July 1999 which came out exceptionally warm and dry, and rather sunny, while June 1999 was slightly sunnier than average there.

One complicating factor is the way Woodford uses a Kipp-Zonen sunshine recorder whereas Ringway used a Campbell-Stokes recorder- the latter are known to overestimate sunshine by 10-15% during the summer half-year. This may lead to 2005-09 coming out with slightly depressed index values. However Summer 2008 was certainly not an average summer- exceptionally wet, and with many parts of the country having their dullest August since 1912.

At one stage I entertained thoughts of using the Met Office's UK-wide stats (freely available to the public here: http://www.metoffice.gov.uk/climate/uk/datasets/index.html#) to estimate what Kevin's index would give for the UK as a whole in summers going as far back as 1961. Not all of the relevant indices are available, but it is possible from what is provided to develop a rough approximation, so I may get around to that shortly.

It's always seemed a chicken-and-egg one to me; does the CS over-record, or the KZ under-record? My own impression, comparing the stats, is that they record similar values in unbroken sunshine but the KZ records much lower in partly cloudy, hazy or sunshine-and-showers. It does seem to me that days with largely unbroken sunshine in June/Jul/Aug have become much rarer since about 1998, while they've got more common from December to March.

Back to those summers; July 1999 was the best summer month here between 1995 and 2006. The stats bear that out as well- it was appreciably sunnier, about half as wet, and slightly warmer than August 2003. June I remember being a classic "mixed bag"- showers, a bit of thunder, some sun, not great but certainly not like June 1997. August was one of the wettest summer months of the 90s here, but it didn't have a large number of raindays unlike 1992.

August 1990 certainly beat 2003 as well; although slightly the wetter of the two up the road at Shawbury (34mm, still well below average) its average max was 1.3C higher and it was about 20 hours sunnier (even if 2003 was CS I think it would still have been duller). July 1990, a month I don't even have that many memories of, recorded a stonking 279.7 hours of sunshine- more than July 2006 or August 1995, and about 90% of the combined total for Jul and Aug 2003.

[damianslaw]

It's always seemed a chicken-and-egg one to me; does the CS over-record, or the KZ under-record? My own impression, comparing the stats, is that they record similar values in unbroken sunshine but the KZ records much lower in partly cloudy, hazy or sunshine-and-showers. It does seem to me that days with largely unbroken sunshine in June/Jul/Aug have become much rarer since about 1998, while they've got more common from December to March.

Back to those summers; July 1999 was the best summer month here between 1995 and 2006. The stats bear that out as well- it was appreciably sunnier, about half as wet, and slightly warmer than August 2003. June I remember being a classic "mixed bag"- showers, a bit of thunder, some sun, not great but certainly not like June 1997. August was one of the wettest summer months of the 90s here, but it didn't have a large number of raindays unlike 1992.

August 1990 certainly beat 2003 as well; although slightly the wetter of the two up the road at Shawbury (34mm, still well below average) its average max was 1.3C higher and it was about 20 hours sunnier (even if 2003 was CS I think it would still have been duller). July 1990, a month I don't even have that many memories of, recorded a stonking 279.7 hours of sunshine- more than July 2006 or August 1995, and about 90% of the combined total for Jul and Aug 2003.

I remember July 1990, at least the second half being consistently dry sunny and very warm in the Lake District. I was 12 at the time and seem to remember almost every day during the summer school holidays being in the local park, it was a summer to rival 1995, and much better in my opinion than 2003 or 2006. Oooh to have a summer school holiday period like those of 1990 and 1995..that six week period is when most people want summer to be at its best, not during the second half of June..

[summer blizzard]

Offical Summer Blizzard forecast 2010.

Don't have time to get into great detail so i will break it down.

Neutral ENSO conditions will persist throughout summer 2010.

Negative QBO will peak in July 2010.

Arctic Occilation will be negative during June and July 2010, positive during August 2010.

June prediction: 15.0C, 0.9C above average - Drier than average

July prediction: 16.1C, 0.4C below average - Wetter than average

August prediction: 16.7C, 0.5C above average - Drier than average

Summer 2010 prediction: 15.9C, 0.3C above average - Drier than average

On the face of it, a summer much like 2009, though the possibility of a fourth straight cool and wet July.

Edited June 13, 2010 by summer blizzard

[Bottesford]

I remember July 1990, at least the second half being consistently dry sunny and very warm in the Lake District. I was 12 at the time and seem to remember almost every day during the summer school holidays being in the local park, it was a summer to rival 1995, and much better in my opinion than 2003 or 2006. Oooh to have a summer school holiday period like those of 1990 and 1995..that six week period is when most people want summer to be at its best, not during the second half of June..

Not me - I like the best summer weather late May to mid July when daylight is at its peak. Sure I'd like August good too but if I had to choose I'd prefer the best weather around the solstice.