January CET

[Thundery wintry showers]

The first third of January 2010 didn't feature any exceptionally cold upper air- the 850hPa values rarely got below -10C over most of the country. In contrast the severe episodes of January 1987 and February 1991 both had 850hPa values around -15C or below for a time.

The cold spell earlier this month was most notable for persistence of sub-zero temperatures over a long period of time, rather than any particularly outstanding individual temperatures. But the persistence was certainly unusual, giving rise to the coldest first 10 days of January for 116 years.

[Cymro]

The first third of January 2010 didn't feature any exceptionally cold upper air- the 850hPa values rarely got below -10C over most of the country. In contrast the severe episodes of January 1987 and February 1991 both had 850hPa values around -15C or below for a time.

The cold spell earlier this month was most notable for persistence of sub-zero temperatures over a long period of time, rather than any particularly outstanding individual temperatures. But the persistence was certainly unusual, giving rise to the coldest first 10 days of January for 116 years.

I dont know mind a few records were broken, Trawsgoed being -15 for a coastal area in Western Wales that sure is cold. Also didnt manchester and Carlile record some really low tempreatures.

[Optimus Prime]

The SW recorded a low of -16.0c. That's exceptionally unusual and the lowest since 1979...possibly on record.

During the winter of 1962/1963 the lowest was -22.2c. This winter has just beaton what that harsh winter could manage at -22.3c.

Part of the reason why 63 didn't get any lower temperatures were because the highlands and northern uplands of Scotland were exceptionally dry due to a persistance of easterly winds.

[Eugene]

Disastrous current CET value for January we might have to put up with a monthly CET of just above 1C

If i forecasted a month that cold nobody would of believed me just a month ago thats for sure

[Snowly does it]

Hadley at 1.7 (1.73 rounded down) to the 29th

Last night was a chilly -2.1 so today will probably see a small drop - but probably not enough to get us to 1.6.

Tomorrow will probably also see a slight drop so finishing figure likely to be 1.6 before adjustments.

Manley is on 1.3

After adjustments perhaps 1.3 - 1.5?

60/40 in favour of the coldest month since Jan 87, definitely the first sub 2 since Feb 91

Coldest Dec/Jan since 81/82, I believe the fourth coldest since 62/63 (after that 76/77, 78-79 and 81-82) but am about to check....

Edit - third coldest Dec/Jan since 62/63 if Jan comes in below 1.7, behind 78/79 and 81/82

Another edit - if 1.5 this will be the 8th coldest Dec/Jan since 1900 - behind the above 2, 62/63 and the 4 'wartime' colds of 1916/1917, 1939/40, 1940/41 and 1944/45

[Weather-history]

11th December - 29th January CET: 1.6C

This is a 50 day period

Question: when was the last occasion we had a 50 day period as cold as this?

I suspect as a guess centred around February 1986

[The PIT]

Surprisingly warm tonight at -0.4c and refusing to fall further not all that windy either. I expect the cet to stay overall where it is at the present time.

[Nick L]

Surprisingly warm tonight at -0.4c and refusing to fall further not all that windy either. I expect the cet to stay overall where it is at the present time.

Fell down to -4c here earlier, risen up a bit now as some cloud has rolled in I think.

[reef]

Can we cut out the arguing. Thanks.

[Mark Bayley]

Surprisingly warm tonight at -0.4c and refusing to fall further not all that windy either. I expect the cet to stay overall where it is at the present time.

And yet down the road its -1.2c, seems to be rising though

Seems my C.E.T guess was a tad on the high side, somewhere round 3.6c was it ??

[Snowly does it]

Well, the update for Hadley has us at 1.7 exactly to the 30th with last night -3.3

If today's maxima are 3.5 or thereabouts it will finish unadjusted at 1.6, any higher and it will finish unadjusted at 1.7

Manley is at 1.2 to the 30th

Finishing, adjusted figure 1.4?? Maybe 1.3.

Or will Hadley and Manley be very different?

[Weather-history]

Here is something interesting, the highest daily CET mean for this January is currently 5.3C, now this could change but look at this list.

At the moment, it is the "lowest" highest daily CET mean for the month of January since 1963, its very close to the 1979 value, so its touch and go whether its is higher or lower than this when its been through the quality control wash

Highest daily CET mean for January over the years

2010: 5.3 (provisionally)

2009: 7.5

2008: 11.2

2007: 10.8

2006: 9.4

2005: 9.2

2004: 9.1

2003: 10.4

2002: 10.3

2001: 7.7

2000: 10.3

1999: 10.0

1998: 10.7

1997: 6.4

1996: 9.6

1995: 8.4

1994: 8.3

1993: 10.3

1992: 10.1

1991: 6.6

1990: 10.8

1989: 9.3

1988: 9.3

1987: 7.5

1986: 9.6

1985: 7.4

1984: 9.3

1983: 10.0

1982: 9.7

1981: 8.6

1980: 6.5

1979: 5.4

1978: 7.2

1977: 8.2

1976: 9.9

1975: 9.4

1974: 8.9

1973: 8.7

1972: 8.4

1971: 10.3

1970: 7.9

1969: 10.2

1968: 9.3

1967: 9.4

1966: 10.2

1965: 9.3

1964: 8.1

1963: 2.4

[Snowyowl9]

MR Data thats another remarkable stat

Well, the update for Hadley has us at 1.7 exactly to the 30th with last night -3.3

If today's maxima are 3.5 or thereabouts it will finish unadjusted at 1.6, any higher and it will finish unadjusted at 1.7

Manley is at 1.2 to the 30th

Finishing, adjusted figure 1.4?? Maybe 1.3.

Or will Hadley and Manley be very different?

1.4c sounds like a very good bet to me could be 1.3c Manley should drop to 1.1c by the 31st.

Coldest month since January 1987??

Not just coldest January since 87.

Edited January 31, 2010 by Snowyowl9

[Weather-history]

Here are the Januarys and their highest values that were equaled or less than that provisional 5.3 and amazingly January 1795 is not on that list because it recorded a daily CET mean of 6.0!

2010: 5.3 (provisionally)

1963: 2.4

1941: 3.9

1940: 5.0

1895: 4.6

1881: 5.3

1871: 4.9

1850: 5.3

1842: 4.5

1830: 2.8

1829: 5.3

1815: 4.7

1814: 0.8

1780: 3.9

Edited January 31, 2010 by Mr_Data

[Nick L]

Here are the Januarys and their highest values that were equaled or less than that provisional 5.3 and amazingly January 1795 is not on that list because it recorded a daily CET mean of 6.0!

2010: 5.3 (provisionally)

1963: 2.4

1941: 3.9

1940: 5.0

1895: 4.6

1881: 5.3

1871: 4.9

1850: 5.3

1842: 4.5

1830: 2.8

1829: 5.3

1815: 4.7

1814: 0.8

1780: 3.9

Jan 1814 was a bit chilly :)

[Optimus Prime]

Here are the Januarys and their highest values that were equaled or less than that provisional 5.3 and amazingly January 1795 is not on that list because it recorded a daily CET mean of 6.0!

2010: 5.3 (provisionally)

1963: 2.4

1941: 3.9

1940: 5.0

1895: 4.6

1881: 5.3

1871: 4.9

1850: 5.3

1842: 4.5

1830: 2.8

1829: 5.3

1815: 4.7

1814: 0.8

1780: 3.9

And the CET outcome for each and every one of them months;

2010 1.4c (?)

1963 -2.1c

1941 0.5c

1940; -1.4c

1895 0.2c

1881; -1.5c

1871; 0.5c

1850; 0.7c

1842; 0.6c

1830; -0.2c

1829; 0.3c

1815; 0.3c

1814; -2.9c

1780; -0.9c

Now that's interesting!...2010 comes in higher out of that selected series. Almost tropical in comparison to most of them.

Should have been colder?

[Nick L]

I think this January will be remembered not because of the depth of the cold, but the longevity of it and the lack of any mild muck - makes a refreshing change.

[ukmoose]

And the CET outcome for each and every one of them months;

2010 1.4c (?)

1963 -2.1c

1941 0.5c

1940; -1.4c

1895 0.2c

1881; -1.5c

1871; 0.5c

1850; 0.7c

1842; 0.6c

1830; -0.2c

1829; 0.3c

1815; 0.3c

1814; -2.9c

1780; -0.9c

Now that's interesting!...2010 comes in higher out of that selected series. Almost tropical in comparison to most of them.

Should have been colder?

Yes indeed - that is what I suggested in the cold spell discussion thread yesterday.

[Weather-history]

Now that's interesting!...2010 comes in higher out of that selected series. Almost tropical in comparison to most of them.

Should have been colder?

I think it would have been if it wasn't for that easterly spell. If it had gone the GFS route and had high pressure over the UK rather than in that cloudy and non-descript easterly flow, it would have been relatively sunny and of course with continuing sharp frosts.

Edited February 1, 2010 by Mr_Data

[Tom D]

So the NW temp tracker number is 1.66 - agonisingly close to my prediction of 1.6c

Do we have to wait for verification etc for the official number from the MO?

[reef]

Hadley is 1.65C provisionally. Yesterday came in at just 0.1C.

http://hadobs.metoffice.com/hadcet/cet_mean_est_2010

It looks like they are currently in the process of adjusting the values:

http://hadobs.metoffice.com/hadcet/cet_mean_2010

[AderynCoch]

The first ten days are looking even colder - the 7th has been downgraded to -4.6C (from -3.9C).

Some days have been increased (the 5.3C maximum is now up to 5.5C), but a slight reduction looks on the cards.

Edited February 1, 2010 by AderynCoch

[chionomaniac]

I was really surprised when the 7th came in at -3'9ºC and with both the minima (-7.5ºC) and maxima(-0.2ºC) recorded. The min and max temperatures being recorded in the CET zones by members on the day seemed a lot lower than Hadley has provisionally come out with. I was also checking the hourly met office updates for the CET sites on the 7th and I can't remember one of them getting that high! Perhaps there will be some downward correction here.

The first ten days are looking even colder - the 7th has been downgraded to -4.6C (from -3.9C).

Some days have been increased (the 5.3C maximum is now up to 5.5C), but a slight reduction looks on the cards.

I knew that day wasn't right all along! No real surprise there.

[Kentish Man]

Climate UK (Manley) have issued their January stats:-

CET: (Jan 1-31): 1.2°C (-3.0 degC)

E&W Rain: (Jan 1-31): 67.6mm ( 72 per cent)

E&W Sun: (Jan 1-31): 67.6hr (122 per cent)

© Philip Eden

[AderynCoch]

E&W Rain: (Jan 1-31): 67.6mm ( 72 per cent)

E&W Sun: (Jan 1-31): 67.6hr (122 per cent)

© Philip Eden

Uncanny!

Has anything like this ever happened before?