April CET

[Milhouse]

11.3c to the 19th. How high will it go!

[Optimus Prime]

11.3c to the 19th. How high will it go!

Low 12.0s by the looka of thinga

[Interitus]

There is less tendency to deviate from the maximum in winter but very large scope for deviation from the minimum. Temperatures of around -15C are a bigger deviation from the average minimum (in England at least) than just about any record high temperature in the summer. And yet such temperatures were recorded quite widely in December. Assuming the average is around 1-2C, this represents a difference of 16-17C from the average. We've only seen that kind of deviation from the max in summer on two or three occasions (I'm thinking August 1990 and 2003). Of course even lower minima were experienced widely in Highland Scotland.

Exactly and fairly obviously due our normal Atlantic maritime influence keeping us mild in winter and cool in summer. Removing the effect of this allows us to have more continental winter cold and summer heat.

Back to April weather, this spell has been quite something, moreso if including the extended period starting in March. Can't help feeling we will pay for this and that there will be no summer again this year!

Edited April 20, 2011 by Interitus

[Thundery wintry showers]

I would prefer cold spells spread through the winter rather than a big one so ludicrously early like in 2010-11 only for the rest of the winter post Xmas to deliver next to nothing.

Depends on how thinly spread the cold spells are. I would certainly prefer a winter with 2010/11's worth of cold and snow, spread out through the season, than have a 2010/11, but I would still take a 2010/11 rather than a "normal" style UK winter with generally mild weather and a thin spread of modest cold snaps. In many ways it's also pretty exciting seeing such a switch-around and having the likelihood of two record-breaking months happening in the space of five, one at each end of the spectrum.

[TonyH]

Has this sort of thing happened before, with record warm (or cold) months of the same name being broken twice in as little as 5 years? Off the top of my head I cannot recall this happening in recent decades.

[reef]

I cant think of any recently. Though there have been examples of years close together where the first and second warmest months on record were recorded:

August

19.2C: 1995

18.9C: 1997

October:

13.3C: 2001

13.1C: 2005

13.0C: 2006

[damianslaw]

I cant think of any recently. Though there have been examples of years close together where the first and second warmest months on record were recorded:

August

19.2C: 1995

18.9C: 1997

October:

13.3C: 2001

13.1C: 2005

13.0C: 2006

The back to back warm octobers in 2005 and 2006 is a very notable statistic indeed. Temps at night in 2005 and 2006 were particularly mild, I remember late October 2005 feeling like August.

The old adage you can't wait a lifetime for a bus then three turn up at the same time. Our weather does what it does and doesn't play to the calandar or what has come before.

[Gavin P]

What I find scary about this April though, is that it looks like its going to be SO far above the previous record.

I mean, all months (and days) have a range from cold to warm and of course within that range records are broken all the time, but its very, very unusual for a month to break the record by over 1c above (or below) the previous record holder- And remember April 2007 was already a fairly substantial deviation from the previous record holder in April 1865. This personally, is what I find very concerning about the extraordinary April 2011.

Edited April 20, 2011 by Gavin P

[Optimus Prime]

Concerning? Enjoy it.

[Gavin P]

Concerning? Enjoy it.

Personally I don't find any enjoyment in seeing the climate I know and love being replaced by something else. I mean, theres having a nice April, with a CET of say 10c. But this April, with a CET probably getting to 12c or above, is just crazy, ridiculous, absurd, worrying, etc...

To put this another way, if July was to show as big a deviation from the previous record holder (July 2006) as April 2011 is going to show from April 2007, we would be looking at a July CET getting on for 21c!!!!!!!!! People don't seem to realise how outrageous this April is.

Edited April 20, 2011 by Gavin P

[Milhouse]

Personally I don't find any enjoyment in seeing the climate I know and love being replaced by something else. I mean, theres having a nice April, with a CET of say 10c. But this April, with a CET probably getting to 12c or above, is just crazy, ridiculous, absurd, worrying, etc...

Did you view December in the same way?

[Backtrack]

And it's forecast to keep getting warmer as the week goes on.

I don't think the record will be smashed. But it will be broken.

[Gavin P]

Did you view December in the same way?

December didn't break the CET record, though it did break some local records in Ireland I think?. Look, I'm not saying its concering to have a record breaking month - The weather is always breaking new ground - Its the amount by which we're going to beat April 2007 (which was itself 0.5c above the previous record holder - a large amount by which to break a monthly record) that I'm concerned about. Of course, this could be just a freak one off, but what if this is the start of another period of extreme heat like we saw from 2006 to 2007, only even more intense than that period?

And it's forecast to keep getting warmer as the week goes on.

I don't think the record will be smashed. But it will be broken.

Indeed. The heat is going to become even more intense over the next few days, which is why I think an April CET of 12c looks on the cards. 12.0 would be 0.8c above the previous record and would surely consitute "smashing" the record in anybodys book?

Edited April 20, 2011 by Gavin P

[Optimus Prime]

Other worrying months in the CET series;

February 1779 7.9c (4.1c above normal)

May 1833 15.1c (3.9c above normal) (second highest 1848 13.9c)

June 1846 18.2c (4.0c above normal)

[stewfox]

Another question could be:

Will we ever see a sub zero month again, that is not part of the mildest winter on record containing a sub zero month, and in a winter that is not a pear shaped winter let alone the most pear shaped winter on record like 2010-11 was?

NEB why dont you give it a rest ? For CET Dec was way below average Jan a bit below average and Feb a fair bit above.

I have no idea what you mean by mildest winter on record ? Pear shaped, best xmas weather I can remember in 40yrs , accept the winter for what it was.

A April CET above May CET would be interesting

Its possble this April could be warmer then June 1972 ? Should beat June 1675 although thats going back to JH era, I cant remember that one :unsure:

[Kentish Kiwi]

Is it really so certain that the April 2007 record is going to be beaten though? The easterly that's been shown on a good few runs looks like it will produce a lot in the way of cloud and cooler temperatures (especially considering how cool some North Sea coastal areas were today)... Could this not peg back the CET considerably? It gets going around the 26th, so that's 5 days where it has the potential to bring temperatures down...

[Gavin P]

Other worrying months in the CET series;

February 1779 7.9c (4.1c above normal)

May 1833 15.1c (3.9c above normal) (second highest 1848 13.9c)

June 1846 18.2c (4.0c above normal)

Did any of those months come just four years after the previous record holder, which was itself over half a degree above the previous record?

[Scorcher]

Is it really so certain that the April 2007 record is going to be beaten though? The easterly that's been shown on a good few runs looks like it will produce a lot in the way of cloud and cooler temperatures (especially considering how cool some North Sea coastal areas were today)... Could this not peg back the CET considerably? It gets going around the 26th, so that's 5 days where it has the potential to bring temperatures down...

It's the Central England Temperature so it won't be affected too much by cloud and cool temperatures that stay on the East Coast. Most of the stations are not severely affected by cloud in easterlies as they are not on the East Coast. In addition I think it would require some cold nights to take the CET below 2007 by that stage and if the cloud did manage to penetrate inland night time minima would be kept up.

[AderynCoch]

Did any of those months come just four years after the previous record holder, which was itself over half a degree above the previous record?

Whilst the exceptional warmth of this April does leave food for thought, I wouldn't read too much into the fact that the record was broken as recently as 2007. It's not as though the record has been broken with increasing regularity in more recent times (before 2007 you had to go back to 1865).

[Upgrade]

Personally I don't find any enjoyment in seeing the climate I know and love being replaced by something else. I mean, theres having a nice April, with a CET of say 10c. But this April, with a CET probably getting to 12c or above, is just crazy, ridiculous, absurd, worrying, etc...

To put this another way, if July was to show as big a deviation from the previous record holder (July 2006) as April 2011 is going to show from April 2007, we would be looking at a July CET getting on for 21c!!!!!!!!! People don't seem to realise how outrageous this April is.

this is so true. I was cycling home this evening having to literal;y pinch myself that this wasn't July. We've gone from early spring to high summer very quickly and all the flowers are really well on. It's felt summery all month. It's totally freaky.

I felt like an idiot when i started watering the lawn on 10th April after weeks without rain, thinking it would probably rain the next couple of days I'm glad i did though now - no rain looks like falling all month.

I am also in the "there will be payback" camp though - still burned by 2007......... enjoy the summer now guys - this might be it!

[damianslaw]

If we do see this April finishing up at or above 12 degrees it will be an exceptional feat, especially considering how it will smash the previous record by 0.8 degrees. But comparing with April 2007 is perhaps not fair, this month started on an exceptionally warm note right from the offset, whereas the warmth in 2007 didn't get going until the 10th - had the warmth of the last twenty days in April 2007 extended into the early part of the month then this month could have easily registered 12 degrees.

I think those concerned with how warm this month may end up need to remember we have probably seen warmer 4 week periods coinciding with non calandar months and had these periods done so many other months would have registered much higher CET values. This year the warm synoptics have coincided perfectly with the calandar month - a rare feat. Dec 2010 saw a similiar thing happen though the cold tapered off markedly in the last 4 days - something I think will happen this April, the heat will dissapear by the 26th.

What has aslo contributed to this months high CET values has been the source of the air predominantly tropical maritime or tropical continental and thus nights have been very mild under the clear skies - not always associated with anticyclonic conditions.

I think April 2011 will go down as one of those freak months. April is the most difficult month to expect the same temps prevail from start to finish it is our most fickle month, hence why only April 2007 has seen a value 3 degrees above the norm. It perhaps was only a matter of time before we were provided with an April which can show for its full worth what it can do in terms of heat - I very much doubt though we will see the likes of this April for a very long time to come - the odds are stacked against such synoptics prevailing for so long in April. We should class ourselves very very lucky just like we could in December for those who seek snow and bone biting persistant cold.

[Kentish Kiwi]

If we do see this April finishing up at or above 12 degrees it will be an exceptional feat, especially considering how it will smash the previous record by 0.8 degrees. But comparing with April 2007 is perhaps not fair, this month started on an exceptionally warm note right from the offset, whereas the warmth in 2007 didn't get going until the 10th - had the warmth of the last twenty days in April 2007 extended into the early part of the month then this month could have easily registered 12 degrees.

I think those concerned with how warm this month may end up need to remember we have probably seen warmer 4 week periods coinciding with non calandar months and had these periods done so many other months would have registered much higher CET values. This year the warm synoptics have coincided perfectly with the calandar month - a rare feat. Dec 2010 saw a similiar thing happen though the cold tapered off markedly in the last 4 days - something I think will happen this April, the heat will dissapear by the 26th.

What has aslo contributed to this months high CET values has been the source of the air predominantly tropical maritime or tropical continental and thus nights have been very mild under the clear skies - not always associated with anticyclonic conditions.

I think April 2011 will go down as one of those freak months. April is the most difficult month to expect the same temps prevail from start to finish it is our most fickle month, hence why only April 2007 has seen a value 3 degrees above the norm. It perhaps was only a matter of time before we were provided with an April which can show for its full worth what it can do in terms of heat - I very much doubt though we will see the likes of this April for a very long time to come - the odds are stacked against such synoptics prevailing for so long in April. We should class ourselves very very lucky just like we could in December for those who seek snow and bone biting persistant cold.

Would just like to say that this is a fantastic post. Fully agree with all of the above.

[reef]

I think April 2011 will go down as one of those freak months. April is the most difficult month to expect the same temps prevail from start to finish it is our most fickle month, hence why only April 2007 has seen a value 3 degrees above the norm. It perhaps was only a matter of time before we were provided with an April which can show for its full worth what it can do in terms of heat - I very much doubt though we will see the likes of this April for a very long time to come - the odds are stacked against such synoptics prevailing for so long in April . We should class ourselves very very lucky just like we could in December for those who seek snow and bone biting persistant cold.

To be fair, this was said after April 2007 aswell. It was seen as a 'perfect storm' sort of a month too. The fact isnt so much thats its going to break the record, but rather that it comes a few years after a previous record was smashed - and it could do so by some way again. It could be said that in 2006/07 July breaking the record was extreme though nothing unusual, but then September and the following April also did, with many very warm months in between. Its the trend that makes it notable. May 1833 was the opposite, quite some way above the previous record, but then it wasnt broken again soon after.

Going by the GFS 18z, the final CET would end up at 12.4C. Thats 1.2C above 2007 which itself was 0.6C above the previous record. Whichever way its looked at, it's going to be a very extreme month.

[Weather-history]

December didn't break the CET record,

It didn't break the CET record, Gavin, but you are splitting hairs here because there was a 31 day period that was 0.7C below that record, which is truely exceptional when taking into account the warmth of the last two decades. Put it this way, would you have predicted a late November to Christmas period returning a CET colder than January 1940 back in July 2006 to happen within the next 5 years?

It was the coldest 31 CET day period since 1963.

The impression I get is that the weather "seems" to have gone a bit extreme in the last 5 years, rainfall, sunshine, temperatures. Specific patterns seem to be enhanced and prolonged such as last year with that Greenland block or 2006 with the persistent southerly flows.

[Gavin P]

The impression I get is that the weather "seems" to have gone a bit extreme in the last 5 years, rainfall, sunshine, temperatures. Specific patterns seem to be enhanced and prolonged such as last year with that Greenland block or 2006 with the persistent southerly flows.

Yeah, the jet stream definately seems to be getting stuck for several months at a time. As you rightly identify we had that extraordinary period from 2006 to 2007 with CET's tumbling left, right and centre. Then we had the summer floods in 2007. Then they cold periods in 2010. Meanwhile in 2010 there was also the Russian heatwave. Europe definately seems to have entered an extreme period of weather.