Stu_London

looks like 3 days of solid rises to come after today, medium term looks to be of a tropical maritime nature so we may have seen the low point for the month, although not possible to rule out a sharpish fall near the month end as the potential for lower daily outcomes increases

I can't remember when it was but the forecaster was Ian MaCaskill....he said the air behind this front is cold, but the air behind this one is 'REALLY' cold. We had trough to our east and we had some true arctic air pile down from directly NNW/N. It dumped a good amount of snow. A virtual pint to anyone who finds that forecast and/or synoptic set up as I think we''ll be hearing some of that IF I goes how I've been thinking all winter with PV utterly disrupted by the SSW [Mini, Minor or half]. December 7th 1990, chap. Can't find it on you tube, but the archive charts show it nicely BFTP

Rare post from me. Don't see a significant cold spell evolving in the first half of January. Bit of a cool zonal set up - nothing blow torch and decent enough for the Scottish Ski industry (although looks quite blowy up there a lot of the time). I'd be surprised if there is much in the way of lowland white stuff in that timeframe.

The GEM has been consistent. Not a guarantee of success but a positive sign nonetheless.

slightly disappointing 0z GFS for coldies Cold is delayed into southern parts until the low res part of the run and then the uppers run out of steam after a short while Some ropey operational runs were inevitable given the ensemble split that has been prevailing and with the overall NH profile looking decidedly dicey this may prove to be a first bite of the cherry scenario as often happens with easterlies. Taking a positive spin on matters, there could be a decent enough battleground situation with possible snow events for some parts in about a week. Additionally, a rather tame easterly effort (or one that even collapses completely) can be followed up by a more sustained cold spell later as happened frequently in the 80s and a couple of times in the mid 2000s, although the latter ones ran into the later part of the season where it all got a bit marginal, something that isn't a problem for us, yet. Edit: Deep FI offers the prospect of a reload of sorts, however the Azores High becomes something of a spoiler and needs to do one. In any event, no point stressing too much over +300 hour output, but something to monitor on future output.

A pleasant turn around with the models over the last 24 hours for those looking for cold (nearly everyone on here lol!) Some words of caution. The NH pattern still looks like it has a lot of variables to overcome before the pattern being shown is locked. Cross model agreement is great but a complete implosion can't be ruled out just yet, although this is looking more unlikely than not. The other thing that 15 years of winter model watching has taught me is that more often than not the really stellar charts are in the 96-144hr range - frequently there are upgrades to this point. As we enter the realms of what can be considered the very reliable timeframe, sometimes there are very small stepped downgrades in terms of upper and surface temps and ppn. In this case some small last minute downgrades shouldn't be a problem if they do occur, as it should still be a reasonably potent cold snap at worst and some people will likely see some snow. Whatever your weather preference, some respite from the battering we have got from the Atlantic should be welcomed universally.

Happy with my guess and the methodology behind it - so far!

ECM continuing with last year's theme of being the 'rampers' model of choice. Even if it did outperform the GFS. I can outperform my wife at running, but doesn't mean I'm any good at it. edit: actually that's not fsir - she would probably win

I'll come wherever it is, health permitting.

6.6C Have a feeling that the MLB we currently see will eventually sink south east into continental Europe. this will open the door for a westerly or south westerly mobile regime. High minima would be the driving factor if this above average prediction were to verify.

10,000,000 mark breached on IJIS (22nd November 2013) The 6th latest date that this mark has been reached. The years when this milestone was reached later are: - 23rd November - 2008 & 2011 26th November - 2012 28th November - 2010 2nd December - 2007 So, whilst we a generally comparing a little more favourably than recent years, we are still quite a long way off historical levels. In fact in most years on this date in the 1980s and 1990s, ice extent had grown to over 11,000,000 sq km

Even if the high does position in a way to give us a colder shot, the jet profile doesn't really support anything other than any brief transitory events as high latitude blocking looks a long way off at present. Mid latitude blocking looks the form horse with high pressure close to the UK for an extended period. Fog, frost and slightly below average temps look likely, all pretty standard for late November / early December. When the pattern does change, cold weather fans do not want to see the high drift south east into Europe, as that will open door for the zonal train for god knows how long.

31st December 1978 Could not comprehend how torrential rain that I went to bed to could turn into a foot of snow by 8am the next day

The only one we can be certain of is the Daily Express, provided there is room in between the house price ramping, Maddy suspect and Diana stories. Much of the remainder of the question may depend on how Solar Cycle 25 pans out. If we are at the start of a grand minimum and SC24 was not a one-off dud, then we might well start to see the effects of localised cooling in North America and North West Europe as was seen during the Dalton minimum some 230 years ago. It probably wont be anywhere as cold as then as we are starting from a much higher base, however we might expect severe winter weather on a more regular basis as perhaps we are becoming used to over the last 5 years, but not necessarily every winter as other factors will sometimes over-ride. We might also get a few surprises (they will become less of a surprise over time) outside of the winter months along the lines of October 2008, April 2009, November 2010, March 2013. Not all bad news if you don't like the cold, grand minimums are also known for short warm fine summers. In fact there were more summer months over 17C in the Dalton Minimum than there were in the last 30 years which were supposedly a warm period in recent climate histories. Summer 2013 might be a good analogue match. You will notice that I have perhaps suggested some anecdotal evidence that the process I have described is already under way, however for this to continue we need SC25 to be as quiet or quieter than the current cycle

Bit of a slowdown with only a 6K increase to the 3rd. Enough to take us up to 7th Lowest as we have now overtaken 2006. http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

Another decent rise for ice extent on IJIS to 8.82sq km . Still 6th lowest, but we will almost certainly rise above 2006 in the coming days, with 2002, 2003, 2005 and the average for the 2000s perhaps all for the taking too.

Refreeze continues steadily if unspectacularly. - Up over 8.6million sq km. Haven't looked at the prospects for the next week, but if the current trend continues we could overtake 2006 again to move up to 7th lowest. Overtaking the 2000s average remains tantalisingly close, but just out of reach it would seem. All based on IJIS data.

Based on IJIS data, we have actually fallen behind 2006 and 2008 in the last few days, so perhaps the refreeze isn't quite as impressive as some think. We are still 1.72 million sq km ahead of 2012 but I expect that gap to close rapidly in the next few days. 2012 gained 1.4 million sq km in the corresponding week ahead last year, which might well be the fastest rate of refreeze over 7 days ever observed.

Interestingly, the 17th September 2013 was recalibrated down to 9.9C, so we are not looking for our first sub 10C day of the Autumn/winter period.

You have to remember that those are average temperatures. DC is right in the battleground area between the sub tropical air coming up Florida and the cold continental air from Canada. I suspect that a maritime influence also contributes to keeping average temperatures higher than more central areas at the same latitude. For me that makes things all the more interesting - in February for example you could easily go from a pleasant 20C to a bone chilling -10C and being buried in snow within a matter of a couple of days. Our climate averages might not be that different for winter, but we have a much more homogenised version thanks to that pesky gulf stream

Had the 16th been sub 10C (and it might be after adjustments as it is currently 10.1C), it would have been the earliest sub 10C day since 1986. 1986 ended up at 11.3C and is the 15th coldest September in the series.

The 06gfs, should it come off exactly, would give us 13.7 or 13.8 before adjustments. Some very mild nights right at the end however, which probably happen, so there is probably more downside risk to that figure. Although the upcoming period looks very pleasant there are probably only 2 days where the CET will be greater than 15C as cooler nights at the start and end of the settled spell may offset the warmth of the days. Outside chance of tomorrow giving us a sub 10C CET day - depends on how low we get tonight and where temps in the zone get supressed tomorrow. If the warmth pushes east a little, we could easily be well over 10C

Somewhere like Virginia or DC in the states would be interesting. Warm summers, cold winters, occasional tornado and hurricane threats. The east coast of South Korea is not dissimilar however a bit wetter and more humid in summer and probably a bit cold in winter.

Looking at the 18z, you couldn't rule out sub 13 categorically. Seems the weekend heat has been downgraded and shortened a little. However it's only one run and a lot of the period to the end of the month is still la la land when it comes to NWP output

CET is 13.8 to the 16th. Yesterday came in at 10.1C. Last night was a little milder than expected at 8.4C, so sub 10C unlikely today. Looks like a fall through until Thursday, with temps rising again over the weekend. I don't expect sub 13C for the month, however it's unlikely to stay too far above average for long enough for anything over 14C to been that likely either.