December CET

[Stratos Ferric]

See above about the 18:30 forecast 7c to 9c in the south on Xmas day. This will halt slide somewhat helped by cloudy nights.

I'm inclined to agree that we're probably through the coldest of this mush now, and in any case, as the current average drops with the passage of time, so it becomes mathematically more difficult to drop further. I don't know how cold it's stayed down south today, but I've got to assume Stonyhurst got up to at least 7 or 8, as that's what I've had and I'm about 30 miles E thereof. Self-interestedly I'd be happy to see the outturn fall below 6.0, but I still can't see it. The projection I posted last Monday still looks fairly tidy, and once we get more breeze in the S over the next couple of days temps geenrally will recover somewhat.

As SM says, the end of the month is still important, but it looks far more likely to be on the mild side than anything else.

[Snowly does it]

I'm inclined to agree that we're probably through the coldest of this mush now, and in any case, as the current average drops with the passage of time, so it becomes mathematically more difficult to drop further. I don't know how cold it's stayed down south today, but I've got to assume Stonyhurst got up to at least 7 or 8, as that's what I've had and I'm about 30 miles E thereof. Self-interestedly I'd be happy to see the outturn fall below 6.0, but I still can't see it. The projection I posted last Monday still looks fairly tidy, and once we get more breeze in the S over the next couple of days temps geenrally will recover somewhat.

As SM says, the end of the month is still important, but it looks far more likely to be on the mild side than anything else.

Certainly the East did not get above 2 today but I don't know about places further west, tonight is round about freezing, pretty much identical to the last 3 nights (which bottomed around -2 in my location).

Yes, mild favourite for post 27/28th, the next few nights will be critical - how much cloud in the system?

[West is Best]

Don't think we're too far from agreement actually Tamara there. But I do think the GFS is really under-estimating temps in this breakdown. The upper air temps will come into play as the inversion loosens its grip. I think we've had a whiff of that last night with temps generally in the range 0C to 2C across southern England (I've seen one -1C and a few above 2C but generally that was the range), whilst the GFS even on the 0z was progging -4C. The 0z run now has much higher temps for next week, but I still think it's under-calling them. Much depends on how close the Bartlett gets to us. At the moment it is still shown over northern France. However, unless it comes right back over I doubt we'll see inversion so the upper air temps become much more significant again.

The official (but provisional) Met Office CET up to 18th Dec was 7.9C http://hadobs.metoffice.com/hadcet/cet_info_mean.html

Edited December 23, 2006 by West is Best

[Roger J Smith]

Wouldn't it be fun if it warmed back up to about 10-12 C and the monthly mean went back up to about 8?

For me that would be fun.

But I think the gradient will have to get stronger than what I'm seeing on the 00z GFS run, either that or include the western Isles in the CET.

I would say more, but I am looking for my shoes.

[West is Best]

Wouldn't it be fun if it warmed back up to about 10-12 C and the monthly mean went back up to about 8?

Well BBC are certainly progging those sorts of temps by the middle of next week, at least to the north-west of London. The GFS still goes for something much cooler on its 2m guestimates. I think double figures are a near-certainty at some stage next week with these upper air temps.

However, I can't see the CET climbing back up to 8C. I'll be lucky to hold on to my 6.8C!

[Snowly does it]

From the link Richard provided in the Nove CET thread, the Hadley would appear to be a little behind Phillip on the 18th? Probably means its about 6.7 now to 6.8 or so for Phillip at a guess.

Certainly looks like the CET will fall, but slowly from now until the 27th and then we will see.

Low 6s look good to me now

[Roger J Smith]

Hey, the only mild ramping I can remember was August, which I mistakenly thought would continue the July pattern, not exactly a rookie mistake when you look back at the records, but an outcome which should help my research a lot when I get around to studying the reasons (not finished with that assessment yet). My CET predictions for Sept, Oct and Nov were all between normal CET and the actual higher values, so no ramping here for those three months. In July I said 17.5 in my seasonal forecast (that wasn't placed in the CET thread) so that's hardly a ramp, is it? Missed that sucker by 2.5 C, something I would have guessed would have been in the other direction had I been told in advance.

June was like October, I was below the actual quite high value slightly in my punt. May was like this month, I went for a near-record and saw it cut short by the last ten days. April was similar, I think in general I was expecting the near-reccord warmth of summer and autumn to dominate spring as well, perhaps not that bad a concept but the numbers show a more sedate warmth; in March I said 6.6 at a point when five days of zero CET were locked in, the actual result was not quite that high but my prediction was structurally sound, it stayed cold to the 23rd and then warmed up. Before that, I was somewhat of a cold ramper last winter,my February actually happened in the first half of March. So don't get SACRA on my case, thanks. Those people leave nasty bruises.

[The PIT]

If it keeps dropping my punt of 6C maybe right.

[Stratos Ferric]

Here's my last projection for this month. As others have argued in other threads, this HP has persisted longer than projected a week or so ago: the slippage in the upturn in the CET following the HP led cooling illustrates this. Not easy to project temps for the next 2-3 days, though I'd reckon this latest set is conservative on the low end. An outturn in the low 6s now looks likeliest: as PP mentioned, closer to the monthly norm than seemed likely a week or so in. That means the annual value will likely be around 10.8C.

Edited December 24, 2006 by Stratos Ferric

[osmposm]

An outturn in the low 6s now looks likeliest...

...and I'm delighted (and amazed) to see that my +6.2 lies bang in the middle of your upper and lower projections.

Edited December 24, 2006 by osmposm

[Snowly does it]

Phillip has the average at 6.65 (6.7 rounded up of course) to the 23rd. To achieve 7 an average of 8 for the remaining 8 days necessary, which looks very unlikely until at least Thursday/Friday.

So low to mid 6s still a favourite (and winning me back my lost steak from November!)

[West is Best]

Phillip has the average at 6.65 (6.7 rounded up of course) to the 23rd. To achieve 7 an average of 8 for the remaining 8 days necessary, which looks very unlikely until at least Thursday/Friday.

So low to mid 6s still a favourite (and winning me back my lost steak from November!)

Yes, possibly!

On the other hand just as it's easy to think when it's mild that it will never again get cold, I think it's easy to be lulled in this spell into thinking temps won't rise: they will. There's also still over a week to go. However, I think above 6.7C is unllikely, albeit not impossible. The night-time minima are key I suspect.

Edited December 24, 2006 by West is Best

[Snowly does it]

Yes, possibly!

On the other hand just as it's easy to think when it's mild that it will never again get cold, I think it's easy to be lulled in this spell into thinking temps won't rise: they will. There's also still over a week to go. However, I think above 6.7C is unllikely, albeit not impossible. The night-time minima are key I suspect.

Certainly today is warmer than I expected and so was last night.

Looks like we may be fighting over 0.1 degrees again!

Yes, nightimes key and how quickly the Atlantic comes in, on the 06z it was really restricted to the 30th and 31st as far as the CET zone goes for a rise.

If it goes over 7 from here I would be astonished, if below 6 equally astonished.

[Stratos Ferric]

Certainly today is warmer than I expected and so was last night.

Looks like we may be fighting over 0.1 degrees again!

Yes, nightimes key and how quickly the Atlantic comes in, on the 06z it was really restricted to the 30th and 31st as far as the CET zone goes for a rise.

If it goes over 7 from here I would be astonished, if below 6 equally astonished.

It's 6.4!

[Snowly does it]

It's 6.4!

huh? What is? The CET right now?

My astonishment would come from the projected temps from here... looks like hovering in the low 6s until the Atlantic comes back in....

[kold weather]

A slow down in the drop of the CEt will occur from now on though, so it won't get much lower then it is now, maybe a drop of say 0.1C for every day we keep this cold set-up for, which still looks to me like being flushed away by the 29th, though granted we are probably out of the coldest part of this set-up.

By the 29th I suspect maxes will rise neatly and like West said, i wouldn't be suprised to see quite a mild 30th/31st, though by this time of the month they probably won't raise the CET by that much unless they really are record breakingly mild which is highly unlikely.

[West is Best]

Yes KW - rather surprised to note that the NW tracker has actually risen slightly through today, implying a mean maximum temp higher than 6.7C in the CET zone. I think the mins are now key. I suspect they won't be that low, but they will determine the outcome from here because we're not likely to see really big maxima until close to the end of the month.

[The PIT]

Shouldn't really alter much from now on although it'll get a push upwards towards the end of the month. Thats if FI warm arrives.

[West is Best]

Shouldn't really alter much from now on although it'll get a push upwards towards the end of the month. Thats if FI warm arrives.

Yes, if the 12z scenario is right then there could be a marked lift towards the end. Somewhere between 6C and 7C seems likeliest I'd have thought. Still in with a very slight chance of getting my 6.8C!

[Don]

My prediction of 5.6 for December isn't looking too good, much like the rest of winter infact!

[MP-R]

From my recordings I'd estimate it to be about 6.4C so for the a country average I'd say about 5.5-5.7C.

[West is Best]

Philip's figure is currently on 6.5C up to this last night http://www.climate-uk.com/graphs/0612.htm

It looks to me as if the fall may well have bottomed out. I'm finding the last week very difficult to judge, mainly because I think the GFS is under-estimating surface temps again, as it has done for the last 48 hours. Even if it's right the figure may not now be much below the current level. Something between 6.7C and 6.9C looks about right to me, although if temps do start rising sharply (as I think they may) 7C is still not completely out of the question.

It's looking like the mildest December certainly since 1994 (6.4C) but possibly 1988 (7.5C).

Merry Christmas everyone!

Edited December 25, 2006 by West is Best

[The PIT]

Getting closer to my 6.0C prediction. Whoah.

[stormchaser1]

getting alot closer to my 6.4c

nigel

[Guest Mike W]

max 11, min 9 on Friday, max of 14 min of 12 on Saturday for Bristol according to BBC 5 day. My 8.5 prediciton not far out by the looks of things, maybe.

Edited December 25, 2006 by Mike W