February CET

[summer blizzard]

This thread can't move forward until we see the final numbers for February -- as of now, the official website is stuck on the value for the 27th. I'm sure everyone is watching for the final values. Then also I would be able to update the table that compares first and second half values, where this past February probably ranks in the top three or four in terms of upward change. Would have to think we'll see the final values later Tuesday.

Second half was 6.8C according to Phillip Eden.

[damianslaw]

What is causing it to take so long to verify - can't remember having to wait six days..??? I suspect we will come in just under 4 degrees thanks to notable downard adjustments.

I meant to say Feb not March in my post.

[Don]

What is causing it to take so long to verify - can't remember having to wait six days..??? I suspect we will come in just under 4 degrees thanks to notable downard adjustments.

I meant to say Feb not March in my post.

Perhaps the delay is due to there being a large downward adjustment to the provisional. I expect the final figure will be in the range of 3.9 to 4.1C.

[reef]

Hadley is confirmed as 3.8C, 0.6C below the 1981-2010 average:

http://www.metoffice...cetml1659on.dat

There was a huge downwards ajustment of 0.6C!

Winter as a whole was 5.07C, so 0.58C above average.

[Don]

Hadley is confirmed as 3.8C, 0.6C below the 1981-2010 average:

http://www.metoffice...cetml1659on.dat

There was a huge downwards ajustment of 0.6C!

Winter as a whole was 5.07C, so 0.58C above average.

Wow that is a big adjustment. Given the very mild last ten days of the month, that's about as cold as we could have hoped for and my guess of 3.2C wasn't so far off after all.

Edited March 6, 2012 by Don

[North-Easterly Blast]

With February 2012 confirmed as having a CET of 3.8 (3.81), it was a month that was on the cool side of the most recent seasonal averages, although close to average or even fractionally above by earlier sets of averages, (1951-80 AVG 3.7), (1941-70 AVG 3.6). All in all a very average month, but masking a very cold first half and very mild second half, in fact the increase in the CET from the first half to the second half was the second largest on record (First half 0.0, second half 7.6), or if not the largest on record.

I will also point out that 2012 was a leap year, and so had a 29 day February. As the last day of the month (leap day) had a CET of 9.6, this would mean that if Feb 2012 had occurred during a common year (a 28 day Feb), then Feb 2012 would have had a CET of 3.6. In reality, in the last 25 years, only the Februarys of 1991, 1994, 1996 and 2010 were colder than Feb 2012. So we have really had the second coldest February in 16 years (Feb 2006 was 3.7, but this was a common year (28 days).

Another fact to mention is that whilst the winter of 2011-12 may have been a milder than average winter overall, believe it or not the post Christmas part of winter 2011-12 was very slightly colder overall than the post Christmas part of winter 2010-11; also in fact the cold spell in the first half of Feb 2012 was colder than anything we had after Christmas in 2010-11. After the intense cold spell in Dec 2010 broke on the 27th never to return, the rest of winter 2010-11 had a CET of 5.0, whereas the entire same part of winter 2011-12, after Dec 27th had a CET of 4.8. Winter 2011-12 has certainly been significantly milder than winter 2009-10 was, and also 2008-09. Winters 2010-11 and 2011-12 were similar post Xmas, but winter 2011-12 brought an average to mild start, as opposed to the exceptional cold spell that 2010-11 had to begin with.

Edited March 6, 2012 by North-Easterly Blast

[Roger J Smith]

Here is the updated table for the half-monthly temperature changes. Since I use the convention of 1-14 being the first half in all cases including leap years, I come up with slightly different numbers than NEB. I think 2012 is second on tie-breakers (second decimal or leap year bias).

1799 .... 7.8 (-1.1 to 6.7)

2012 .... 7.8 (-0.2 to 7.6)

1900 .... 6.6 (-0.7 to 5.9)

1803 .... 6.5 (+0.2 to 6.6)

2009 .... 6.2 (+1.0 to 7.2)

1876 .... 6.1 (+1.7 to 7.8]

1917 .... 6.1 (-2.2 to 4.0)

1991 .... 6.1 (-1.5 to 4.6)

1773 .... 6.0 (-0.8 to 5.2)

1841 .... 5.7 (-0.4 to 5.3)

1912 .... 5.6 (+2.5 to 8.1)

1830 .... 5.4 (-0.5 to 4.9)

1911 .... 5.3 (+2.2 to 7.5)

1895 .... 5.0 (-4.3 to 0.7)

1953 .... 5.0 (+1.8 to 6.8]

Some other comments on the other years can be found back in the original post #222.

The mean was -0.9 C for the first twelve days. This is also interesting, the coldest non-calendar month of the winter turns out to be 14 Jan to 13 or 14 Feb, both round off to 2.2 C. This is because of a few rather cold days in mid-January and only a modest warmth between that spell and the main cold spell which set in on 28 January.

So I would say, adjustment or not, February was a classic month of two halves that matched the most extreme cases previously known.

[Weather-history]

The winter of 2011-12 is similar to the winter of 100 years previous 1911-12 in that a cold spell was lost in the overall figures

They both have winter CETs of 5.1

The hidden cold spell

22nd January-5th February 1912: -0.6

29th January-12th February 2012: -0.6

[AderynCoch]

Warmest February 23rd on record this year, 11.7C beating the old record of 11.5C in 1990.

[J10]

After much patience I can now publish the results for February.

Two players in February got 3.8c correct being BARRY and Timmy H.

Dr Hosking and Aaron were 0.1c out.

The top 3 in the year to date and the final scores for Winter are identical.

Timmy H won (also known as Froze were the Days), Styx was 2nd with Thundery wintry showers 3rd.

Particular mention must go Timmy H who had December and February spot on and was only 0.1c out in January, probably the best seasonal accuracy ever.

Full stats have been downloaded below.

Feb 2012 CET.pdf

Feb 2012 CET.xls

[damianslaw]

As anticipated a big downward adjustment - though it was bigger than I thought - I was expecting 0.4 degrees, but 0.6 degrees is very significant. Some of the very cold nights early in the month were woefully under represented I seem to remember when the rolling CET values kept coming through.

So our first below average month since August and comfortably the coldest month of the winter season. The first 11 days really were very cold, we had a very good chance of seeing our coldest Feb since 91 had the PV played ball but it wasn't meant to be.

Recent months have seen some notable marked downward adjustments in CET values.

[DR Hosking]

Hurah, at last my uneducated guess nearly hits the jackpot!

[North-Easterly Blast]

As anticipated a big downward adjustment - though it was bigger than I thought - I was expecting 0.4 degrees, but 0.6 degrees is very significant. Some of the very cold nights early in the month were woefully under represented I seem to remember when the rolling CET values kept coming through.

So our first below average month since August and comfortably the coldest month of the winter season. The first 11 days really were very cold, we had a very good chance of seeing our coldest Feb since 91 had the PV played ball but it wasn't meant to be.

Recent months have seen some notable marked downward adjustments in CET values.

February 2012 was on the cool side of the most recent seasonal average, but it was close to the average for 1961-90 and earlier sets of averages - so it wasn't exactly a below average month. Feb 2012 was close to average for the CET, or on the cool side of the most recent seasonal average. I would for example call a Feb like 2010 cold, but Feb 2012 wasn't that cold. It is like saying, that if the Feb CET had have been around 4.5, then many woud have called it warm, when there is less than 1*C difference between a threshold of a cold month and a warm month.

[reef]

February 2012 was on the cool side of the most recent seasonal average, but it was close to the average for 1961-90 and earlier sets of averages - so it wasn't exactly a below average month. Feb 2012 was close to average for the CET, or on the cool side of the most recent seasonal average. I would for example call a Feb like 2010 cold, but Feb 2012 wasn't that cold. It is like saying, that if the Feb CET had have been around 4.5, then many woud have called it warm, when there is less than 1*C difference between a threshold of a cold month and a warm month.

I dont think anyone would call a 4.5C February 'warm', it would be seen quite rightly as a pretty average month.

Its moving the goalposts a bit using different averages to suit. Its almost always been the case that the most recent 30 year average is used to decide where a month stands. I dont see how a 3.8C February can be called anything other than below average or cool.

[summer blizzard]

1981-2010 or 1701-2011 average are the only ones i will go by.

[North-Easterly Blast]

I dont think anyone would call a 4.5C February 'warm', it would be seen quite rightly as a pretty average month.

Its moving the goalposts a bit using different averages to suit. Its almost always been the case that the most recent 30 year average is used to decide where a month stands. I dont see how a 3.8C February can be called anything other than below average or cool.

A 3.8 February CET is on the cool side of the most recent seasonal average, but putting it into perspective with the larger picture it would be seen as a pretty average month, when compared to 1961-90 and 1951-80 averages, which are still sets of averages measured since World War 2.

I think that for a February to be seen as cool or cold, rather than close to average, I think that the CET needs to be below 3.5*C.

Certainly I would call a Feb like 2010 cold, not close to average.

Edited March 7, 2012 by North-Easterly Blast

[damianslaw]

February 2012 was on the cool side of the most recent seasonal average, but it was close to the average for 1961-90 and earlier sets of averages - so it wasn't exactly a below average month. Feb 2012 was close to average for the CET, or on the cool side of the most recent seasonal average. I would for example call a Feb like 2010 cold, but Feb 2012 wasn't that cold. It is like saying, that if the Feb CET had have been around 4.5, then many woud have called it warm, when there is less than 1*C difference between a threshold of a cold month and a warm month.

Any CET that comes in below the average CET figure is technically below average in my book - doesn't matter if it is only 0.1 degree or 3 degrees below it is still below.

[leicsnow]

We've finally had a below average month, the first since August. How normal is it to see this many consecutive months without a month with a CET at least 1.0 below average?