January 2013 CET (2012/13 Competition)

[Relativistic]

It will be close for below the 1961-90 average by the looks of things now.

[summer blizzard]

Today's minimum is 2.2C while maxima were around 9C, so an increase tomorrow to 3.1C is likely tomorrow.

After that, the 12z GFS has the CET at

3.2C to the 28th (5.3)

3.4C to the 29th (9.5)

3.6C to the 30th (9.0)

3.7C to the 31st (6.0)

No chance of a sub 3.0C finish now unfortunately.

If we can get a correction to 3.4C that will do me.

[Summer Sun]

Up-to 3.1c to the 27th

[Summer Sun]

3.2c to the 28th

[BornFromTheVoid]

Minimum today of 3.1C and maxima around 13C, should result in an increase to 3.4C on tomorrows update.

With the 12z GFS, we'd then be on

3.6C to the 30th (8.4)

3.7C to the 31st (6.9)

Probably around 3.5C as a final figure after corrections methinks.

[godber]

3.5c would suit me fine!

[DR Hosking]

3.4c to the 29th

[Summer Sun]

3.6c to the 30th

[BornFromTheVoid]

Today will probably average close to 8C, so a provisional 3.7C is pretty much assured now.

Just a case of what the corrections will do.

[Stu_London]

I can see some downward movement - was suprised at some of minimums when they were put up.

[Optimus Prime]

An almost perfect distribution of above average/below average days. Looking at the provisional figures 15 days above and 16 days below normal. Despite so many warm days this month the cold intense enough to weight the average down (solely due to mean maxima)

A surprising below average month. By around or just slightly more than half a degree.

[Relativistic]

3.5C is the final figure:

http://www.metoffice.gov.uk/hadobs/hadcet/cetml1659on.dat

[North-Easterly Blast]

A slightly below average January, and colder than most Januarys since 1988, although in the last 100 years, 32 Januarys were colder. It just goes to show how very mild weather in the first eight days and in the last few days of the month can obliterate a spectacular two week cold spell with widespread snowfall at times and mean that the month's mean temperature is not far from average. Despite it being very cold for two weeks of the month with large areas of the country being snow covered for more than a third of the month, the month as a whole actually didn't end up especially cold. Had there been more nights with severe frosts and low minima during the cold spell then we could have easily seen the month's CET below 3*C.

Edited February 1, 2013 by North-Easterly Blast

[Roger J Smith]

If I could run faster I could beat Usain Bolt. Or if I could start at the 50-metre line, that might give me a chance too.

[Don]

3.5C is the final figure:

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

Well that's 4 out of the last 5 January's to record a CET below the 61-90 average which isn't so bad. Could you imagine the prospect of having this at say the end of January 2008?! As others have said, it was a shame that we didn't have colder nights during the two week cold spell. I agree that this was the main reason for it not being somewhat colder rather than the mild start and finish. Still never mind, January 2013 should be one to remember for many, even though it was certainly no 1985, 87 or 2010. We may not have had stunning synoptics this winter, but we've done pretty well considering and we still have another month of proper winter to go. If you think back a few years ago, some were thinking that we needed stunning synoptics just to get below average let alone well below!

Edited February 1, 2013 by Don

[damianslaw]

Another below average month - once again though a month of stark contrasts, with very mild weather cancelled out by cold weather. The mean masks the very varied conditions experienced this month, its been a bit like Jan 2001 and 1996 which saw mild weather balanced out by notable cold period.

As others have stated had we seen clearer skies during the cold spell then we should have comfortably ended up in the 2's. However, it was always going to be a tall order to achieve a significantly below month given the exceptionally mild first third.

[BornFromTheVoid]

Other than January 2010, the recent run of below average Januaries haven't been much below. Going by cumulative anomalies, compared to 61-90 average, the last 2 above average Januaries more than cancel out the last 4 below average.

Also, in the last 15 years we've recorded 6 Januaries with an anomaly of +1.5C or more. To gather 6 Januaries with -1.5C or lower, we have to go back 51 years.

We had a similar run back around the beginning of the 20th century. In the 42 years from 1898 until 1939, only 3 Januaries below -1.5C were recorded. This was ended with a run of January CET values of -1.4C, 0.5C and 0.9C from 1940-1942.

Hopefully we'll get a similar run of very cold Januaries again soon!

[North-Easterly Blast]

Other than January 2010, the recent run of below average Januaries haven't been much below. Going by cumulative anomalies, compared to 61-90 average, the last 2 above average Januaries more than cancel out the last 4 below average.

Also, in the last 15 years we've recorded 6 Januaries with an anomaly of +1.5C or more. To gather 6 Januaries with -1.5C or lower, we have to go back 51 years.

We had a similar run back around the beginning of the 20th century. In the 42 years from 1898 until 1939, only 3 Januaries below -1.5C were recorded. This was ended with a run of January CET values of -1.4C, 0.5C and 0.9C from 1940-1942.

Hopefully we'll get a similar run of very cold Januaries again soon!

A month's CET 0.1 to 0.3C below average is hardly worth talking about. Any month that is between 0.5*C below average and 0.5*C above average is clearly in the close to average category. For the cold category you need to be talking about a month being 1 to 2*C below average; equally I would not call a month only fractionally above the long term mean as mild / warm. Certainly I would call a Jan like 2010 cold; even Jan 2009 was still on the cold side with 3.0, but to say that Jan 2013 is in the cold category at 3.5 is stretching it a bit, when it was only 0.3*C below the 1961-90 mean, it was still in the close to average category.

[Don]

Certainly I would call a Jan like 2010 cold; even Jan 2009 was still on the cold side with 3.0, but to say that Jan 2013 is in the cold category at 3.5 is stretching it a bit, when it was only 0.3*C below the 1961-90 mean, it was still in the close to average category.

Well, compared to the 71-00 mean and more especially the 81-10 mean, January 2013 was in the rather cold category being 0.7C and 1C below normal. It may not have been in the cold category compared to the 61-90 mean, but compared to many January's of the last 15 years, it was certainly on the cold side. That was the main point of my earlier post.

Edited February 2, 2013 by Don

[reef]

Well, compared to the 71-00 mean and more especially the 81-10 mean, January 2013 was in the rather cold category being 0.7C and 1C below normal. It may not have been in the cold category compared to the 61-90 mean, but compared to many January's of the last 15 years, it was certainly on the cold side. That was the main point of my earlier post.

Indeed, Ill never understand why people are using an average that is now 23 years old! Why 1961-1990, why not 1921-1950? They're both pretty irrelevent now.

As you say, compared to the most recent average its a decently cold month at 0.9C below average.

[Thundery wintry showers]

I think the main reason why some prefer the 1961-90 average is that it is more representative of the 20th-century average, which makes sense when running a long-term climatological analysis (though personally I would rather use the twentieth-century average for that purpose, or maybe 1951-2000 if the records from 1901-1950 are relatively sparse/questionable.

But when judging a past month's weather relative to "normal" it makes far less sense to compare with an out-of-date reference period. The current editors of Weather share this view and have pushed hard to get 1981-2010 installed as the default reference period for their Weather Log data. Of course, comparing with different periods need not be mutually exclusive- for example Philip Eden in his Weather Log entries will sometimes point out that a month was slightly colder than average relative to the most up-to-date 30-year mean, but that more than half of the previous 100 were colder.

Edited February 2, 2013 by Thundery wintry showers

[ScottSnow]

Not sure whether this is in the right thread but where can I get a list of monthly CET's ?

[BornFromTheVoid]

I used the 61-90 average because I was discussing years going back well into the 20th century. If someone is only mentioning the last 2 years, then fair enough, use the most recent 30 year mean. But when discussing a range of decades, there little point in using the mildest 30 year period on record for meaningful comparisons.

Not sure whether this is in the right thread but where can I get a list of monthly CET's ?

You can download the CET data here http://www.metoffice.gov.uk/hadobs/hadcet/data/download.html

[ScottSnow]

I used the 61-90 average because I was discussing years going back well into the 20th century. If someone is only mentioning the last 2 years, then fair enough, use the most recent 30 year mean. But when discussing a range of decades, there little point in using the mildest 30 year period on record for meaningful comparisons.

You can download the CET data here http://www.metoffice...a/download.html

Thanks

[J10]

5 players got it spot on this month.

mulzy, Skeggy blizzard, Ben_Cambs, godber and TomSE20

The overall 1-2-3 in the overall comp is mulzy, TomSE20 and Muffelchen

The overall 1-2-3 in the winter comp is mulzy, Rybris Ponce and seabreeze86

Full Scores to be uploaded here later.

Edited February 2, 2013 by Jackone