April CET

[Optimus Prime]

8.4 to the 14th, 1.5c

http://hadobs.metoff..._info_mean.html

Doesn't quite tell the whole story.

Mean Max 12.7c (+2.1c)

Mean Min 4.0c (+0.8c)

[AderynCoch]

CET seems to be levelling out. With no significant changes on the horizon 8-9C is looking like the ballpark, though there's still plenty of time for new developments to occur.

[SteveB]

8.3c to the 15th, 1.3c

http://hadobs.metoffice.com/hadcet/cet_info_mean.html

[Fozfoster]

8.3c to the 15th, 1.3c

http://hadobs.metoff..._info_mean.html

STOP at that please, but i can only see it going higher.

[stewfox]

STOP at that please, but i can only see it going higher.

The weather forcast suggest not.

Not a big drop but with some chilly nights coming up we could see it drop back to around 8c within the reliable time frame (next 5/6 days)

Edited April 16, 2010 by stewfox

[damianslaw]

Some cold nights over the next few days will prevent the CET from rising significantly, whilst maxima look around average if not slightly below by early next week I can see the CET being lower than it currently this come middle of next week.

Still believe the eventual CET will be below 9 degrees, and still think it will end up above average finishing mark probably somewhere between 8.5 and 9 degrees with low benchmark of 8 degrees.

[summer blizzard]

Models show the last ten days of April looking very warm, especially in regards to maxima, so i'm going to have to say between 9C and 9.5C, so about a degree off from my prediction.

Also, what are the record sunshine figures for April, i'd expect south west England to smash the record.

Edited April 17, 2010 by summer blizzard

[SteveB]

8.3c to the 16th, 1.3c

http://hadobs.metoffice.com/hadcet/cet_info_mean.html

[damianslaw]

Models show the last ten days of April looking very warm, especially in regards to maxima, so i'm going to have to say between 9C and 9.5C, so about a degree off from my prediction.

Also, what are the record sunshine figures for April, i'd expect south west England to smash the record.

Not sure about the whole of the last 10 days of the month being very warm, the first of these last 10 days will be Wednesday, which at this stage is looking rather cool more so in the north but average at best in the CET zone, perhaps the last 7 days will be predominantly mild in the CET zone - still beyond the reliable timeframe. Nights look predominantly cool for the foreseeable future if not rather cold for the time of year which will cancel out any mild maxima.

[SteveB]

I am sure whwn I did an update yesterday it was 1.3 above average to the 16th. Stil to the 16th but now showing 1.2c?

[Stu_London]

I am sure whwn I did an update yesterday it was 1.3 above average to the 16th. Stil to the 16th but now showing 1.2c?

It's to the 17th now.

[North-Easterly Blast]

Again we avoid a cold April. It is now 21 years (1989) since the last significantly (0.5*C below or more) below average April. Will we ever see a cold April EVER AGAIN? I mean to say will a cold April on the lines of Aprils 1989 (6.6), 1983 (6.:lol:, 1978 (6.5), 1970 (6.7) or even 1986 (5., ever occur again in the UK? We at last have seen a significantly below average winter season in the UK, and the first month below 2*C since 1991, and the first colder than average February of note since 1996, but so far to follow on we have still not seen a cold April or even a notably below average spring month (March 2010 was just below the 71-00 mean but it wasn't cold by 61-90 standards).

We don't seem to be able to achieve a CET below 8*C in April any more. On rare occasions we have slipped just below this in the last 20 years but "cold" Aprils have just become extinct in the UK. When you look at the CET for each month, it is April that we now have to go back the furthest time to find an instance of where the CET was even more than 0.5*C below average. After the first truly cold winter for so long in the UK this year I was hopeful that we may finally see a cold spring, as historically cold winters have often been followed by below average spring months, but hopes have been dashed again.

This is so strange as winters with sub 3*C CETs at least have often co-incided with colder conditions in general during the other months of the year. It would seem so highly unusual to be able to achieve a sub 3*C or even a sub 3.5*C winter season and not be able to achieve some below average months at other times in the year.

Edited April 18, 2010 by North-Easterly Blast

[joggs]

Again we avoid a cold April. It is now 21 years (1989) since the last significantly (0.5*C below or more) below average April. Will we ever see a cold April EVER AGAIN? I mean to say will a cold April on the lines of Aprils 1989 (6.6), 1983 (6., 1978 (6.5), 1970 (6.7) or even 1986 (5., ever occur again in the UK? We at last have seen a significantly below average winter season in the UK, and the first month below 2*C since 1991, and the first colder than average February of note since 1996, but so far to follow on we have still not seen a cold April or even a notably below average spring month (March 2010 was just below the 71-00 mean but it wasn't cold by 61-90 standards).

We don't seem to be able to achieve a CET below 8*C in April any more. On rare occasions we have slipped just below this in the last 20 years but "cold" Aprils have just become extinct in the UK. When you look at the CET for each month, it is April that we now have to go back the furthest time to find an instance of where the CET was even more than 0.5*C below average. After the first truly cold winter for so long in the UK this year I was hopeful that we may finally see a cold spring, as historically cold winters have often been followed by below average spring months, but hopes have been dashed again.

This is so strange as winters with sub 3*C CETs at least have often co-incided with colder conditions in general during the other months of the year. It would seem so highly unusual to be able to achieve a sub 3*C or even a sub 3.5*C winter season and not be able to achieve some below average months at other times in the year.

Fully agree with you NEB. I personally believe(no proof,scientific backup) but with ocean cycles and the suns inactiveness, Aprils will start becoming gradually cooler over time(not all) But there again who knows with the weather!

[North-Easterly Blast]

Fully agree with you NEB. I personally believe(no proof,scientific backup) but with ocean cycles and the suns inactiveness, Aprils will start becoming gradually cooler over time(not all) But there again who knows with the weather!

The coldest source in April is from a strong Greenland High and long draw northerlies. Even a cyclonic north-westerly pattern often brings the temperature below average. This pattern was dominant in April 1986, and it was the first three weeks that were the centerpiece of this cold (5. April. The centerpiece of April 1978 (6.5) was a Greenland High and a spell of long draw northerlies in the second week. The first half of April 1970 was hugely dominated by this pattern. The main source of the low CET in April 1983 was cyclonic low pressure sat over the UK with the air NW'ly or polar maritime sourced. The second half of April 1981 saw long draw northelies from a Greeny High which gave an unusually late widespread blizzard, although the overall CET wasn't that cold due to a warm first half.

We just do not seem to be able to get this pattern in April any more to attain a low CET for the month. On rare occasions in the last 20 years we have managed a pattern of this type for a time around mid-April 1998, early April 2000 and from around the 5th to 19th April 2008, but for a cold April CET you would be looking for a pattern of this type for a prolonged length of time, intermingled by patterns of high pressure extending over the UK from the north, which can allow enough cold surface air for some notable night frosts in April. Unlike in the winter months, easterlies are not that cold in April as there is usually very little cold air left on the continent by then.

[joggs]

The coldest source in April is from a strong Greenland High and long draw northerlies. Even a cyclonic north-westerly pattern often brings the temperature below average. This pattern was dominant in April 1986, and it was the first three weeks that were the centerpiece of this cold (5. April. The centerpiece of April 1978 (6.5) was a Greenland High and a spell of long draw northerlies in the second week. The first half of April 1970 was hugely dominated by this pattern. The main source of the low CET in April 1983 was cyclonic low pressure sat over the UK with the air NW'ly or polar maritime sourced. The second half of April 1981 saw long draw northelies from a Greeny High which gave an unusually late widespread blizzard, although the overall CET wasn't that cold due to a warm first half.

We just do not seem to be able to get this pattern in April any more to attain a low CET for the month. On rare occasions in the last 20 years we have managed a pattern of this type for a time around mid-April 1998, early April 2000 and from around the 5th to 19th April 2008, but for a cold April CET you would be looking for a pattern of this type for a prolonged length of time, intermingled by patterns of high pressure extending over the UK from the north, which can allow enough cold surface air for some notable night frosts in April. Unlike in the winter months, easterlies are not that cold in April as there is usually very little cold air left on the continent by then.

I agree with easterlies not been too cold this time of year, I personally believe its a case of waiting for the right synoptics at the right time? Ithink thats what i remember looking back from been a sprog!?!? thanks for the informative posts

[damianslaw]

The coldest source in April is from a strong Greenland High and long draw northerlies. Even a cyclonic north-westerly pattern often brings the temperature below average. This pattern was dominant in April 1986, and it was the first three weeks that were the centerpiece of this cold (5. April. The centerpiece of April 1978 (6.5) was a Greenland High and a spell of long draw northerlies in the second week. The first half of April 1970 was hugely dominated by this pattern. The main source of the low CET in April 1983 was cyclonic low pressure sat over the UK with the air NW'ly or polar maritime sourced. The second half of April 1981 saw long draw northelies from a Greeny High which gave an unusually late widespread blizzard, although the overall CET wasn't that cold due to a warm first half.

We just do not seem to be able to get this pattern in April any more to attain a low CET for the month. On rare occasions in the last 20 years we have managed a pattern of this type for a time around mid-April 1998, early April 2000 and from around the 5th to 19th April 2008, but for a cold April CET you would be looking for a pattern of this type for a prolonged length of time, intermingled by patterns of high pressure extending over the UK from the north, which can allow enough cold surface air for some notable night frosts in April. Unlike in the winter months, easterlies are not that cold in April as there is usually very little cold air left on the continent by then.

Indeed recent Aprils have seen an absence of long protacted periods with such cold synoptics. We have seen some long draw northerly spells but these have been relatively short lived i.e. early april 2000, mid April 1999 and mid April 1998 spring to mind.

April is a very fickle month, cold periods can often be quickly replaced by mild/warm spells. High pressure during April generally gives average maxima at its lowest if not mild maxima, unless it pools in cold air which is quite difficult though not impossible i.e. April 1986. You really do need a long period of northerlies or a cyclonic spell with polar air wrapped around the low pressures and little sunshine. The sun is getting very strong during April and will quickly raise temps to at least average and as said a long cloudy spell would only come courtesy of easterlies which by April are not particularly cold and also would reduce risk of cold nights. In overview, it is much harder to get synoptics which will bring sustained cold in April relative to the average than in many other months of the year, similiar to September in this respect.

[Weather-history]

On rare occasions we have slipped just below this in the last 20 years but "cold" Aprils have just become extinct in the UK.

I think you need to re-word that becomes extinct means no longing existing and never will exist again. How do you know we will never see a cold April?

I have heard this kind of talk applied to the winter season and of course this turned out to be not true.

Incidentally, there were 11 Aprils from 1862 to 1872 that didn't drop below 8.0C and the lowest of those was 8.2

[Guest North Sea Snow Convection]

Yes, we have been through all this nonsense regarding cold winter synoptics being 'extinct' as you say. Now that myth has been shattered, the same principle is being tried with something else.

It is only a matter of time before April breaks the pattern and we get another cold one like, say, 1986.

[SteveB]

8.4c to the 18th, 1.1c

http://hadobs.metoffice.com/hadcet/cet_info_mean.html

[Milhouse]

8.4c to the 18th, 1.1c

http://hadobs.metoff..._info_mean.html

Expect a rise from the weekend onwards, possibly a significant one if the ecm is to be believed.

[damianslaw]

CET has been remarkably static over the past few days hovering between 8.3 and 8.4 degrees, can't see this changing much until we get to the weekend when it will very much likely rise, still think 9 degrees is the limit.

[stewfox]

CET has been remarkably static over the past few days hovering between 8.3 and 8.4 degrees, can't see this changing much until we get to the weekend when it will very much likely rise, still think 9 degrees is the limit.

The forcast for the next 10 days suggest 10c is nearer the mark, with another good warm up from mid week on

[AderynCoch]

9C is certainly on the cards now (I can definitely kiss my 7.8C goodbye). 10C looks out of reach unless the warmth is being underprogged.

[summer blizzard]

Next week (edge of reliable timeframe) looks like recording very high maxima for the time of year, so we will probably see the CET end up about 1C above average by my calculations, though the lack of rainfall and exceptional sunshine figures are of more note this month.

Also, does anybody have the highest daily maxima figures handy for the last five days of April??

Edited April 20, 2010 by summer blizzard

[stewfox]

9C is certainly on the cards now (I can definitely kiss my 7.8C goodbye). 10C looks out of reach unless the warmth is being underprogged.

10c looks very in reach. After thursday it max 18/19c and mins 7/9c. A number of 70s will be hit over the weekend if the forecasts are to be trusted

Make the most of the last few chilly nights

Edited April 20, 2010 by stewfox