Uncle_Barty

Also worth looking at the WV images too. The presence of a dark streak (i.e. dry, cold air} behind the developing storm 'head' could be fuel for the 'bomb'. This was clear as Bawbag developed last week.

The 2120 reading from Southampton Airport a few miles along the M27 from you is 993. Should be a pretty good guide. Not looking forward to the daily drive to Whiteley tomorrow morning if this keeps up... Hamble Bridge will be treacherous.

I'd be very suspicious of that ECM operational for now.. as things stand it is completely on its own relative to all the model output and its own previous runs over the past two days WRT Thurs/Fri. Lets see if the other models (and its own later runs) fall into line with the ECM by this time tomorrow..... Definitely a case of 'more runs needed'.......

THursday/Friday will be Bawbag Mk II according to GFS, MetO have it less intense and further south.

While there is no change in the general upper air pattern, it's hard to see any change from zonal, be it average-cold or average-mild. I can't see much change from what we have now for the forseeable future. Just like last summer!! That's not to say it will stay like this till mid-Jan or beyond, no-one can say that for sure, but experience suggests that continuation of the present pattern is the form horse as these patterns can be locked in for many weeks. If things do change, we may not get much more than a week's notice unless it's in the form of a SSW or some other big changes in the various teleconnections.

Just gone through here in Bournemouth. Nothing too spectacular really.

Seen it spelt both ways! It's a somewhat crude expression, thats all I'm saying!

Some of the Scots at work are calling this "Hurricane Bob Agg!"

Just looked at a WV image and there is a very dark area to the rear of the low.. indicates dry rapidly descending air which may lead to a sting jet scenario. Good write-up on such a scenario here: http://www.eots.co.uk/reports/bomb/bomb01.htm

What model is showing that? Looked at the three main models and there is no sign of height rises to NE.. OP - no sign of any height rises to the south. Just an almost static zonal pattern with temps average to maybe a little below average is what it looks like to me.

Not necessarily - it's where the high pressure sets up, and the orientation of the jet. At the moment it is negatively tilted, i.e. NW-SE whereas it is more often positively tilted (SW-NE, leading to milder or very mild weather). A few days ago, the models were leaning towards the latter scenario but is it is I don't think anyone can tell what will happen 10 days from now with the general pattern, other than it will most likely still be zonal. On another note - I would be surprised to see any lowland snow down south. One for Mr. Data - any recorded instances of widespread lowland snow in the South from a PM N-westerly?

Cold strat most likely to lead to strong polar vortex. makes high lat blocking (often a key ingredient to sustained cold weather) much less likely, and zonal conditions much more likely. Doesnt necessarily mean blowtorch southwesterlies though.

C - have you tried using a web proxy to get to the site? Looking at the 06z ensembles, high pressure building down here seems to be the form horse, supported by most members by this time next week.

Why?

Very good agreement on the ensembles down here to the 7th.. but op is among the coldest members 10th onwards.

WB.. for much of the south the -5 air only just makes it, and then only for a short time. WE have a couple of shortwaves to come through before then so a lot can change. In any case even -8 air has produced rain rather than snow here. I would be genuinely shocked if we got any (never mind heavy) snow down here in the next week or two as we rarely get any in a NW'ly..

HC.. probably, as we'd need - IMO - the greeny high needs to be supported by the building of heights there. An upper ridge towards Greenand would be shortlived as it would likely soon be swept aside by the jet with the strong PV in place.

F1 isn't until next March. I don't think it will downgrade as much as you say and it looks like Scotland is in for a few days of colder weather even if things downgrade quite a bit as I said a couple of pages ago.

Years of experience watching the models, particularly the GFS (and its prdecessor the MRF) where time and again a cold spell/snap is shown, then as time gets nearer, it gets further and further downgraded to the point that by the time it arrives it is a short-lived damp squib. This is especially true when it comes to strong PV setup/northwesterly outbreaks and topplers as the next shortwave pushes things further east. I am not saying that will happen this time (though it's a likely scenario for the South) but it's a likely outcome IMO. It does look unsettled with temps a little below average down here and colder further north for the next week or so, beyond that who knows whether it will continue in that vein or whether heights build to the south assuming the PV stays strong.

I cant see anything in that chart to interest the coldies. And who on earth is Mark Vogan?

A lot of it will most likely be marginal though away from high ground, and the continuing strat pattern/PV makes it likely IMO that the cold will get downgraded as the pattern eventually flattens out. Would put FI at 120 hours for that reason. I do not think there will be any snow south of the M4 except on the highest ground, personally. No real sign of a reversion to the very mild conditions of most of this month at the moment however.

Ohh.. ok!

WS, What is the link to those charts please?

Looking zonal/cool zonal for the foreseeable with some agreement that it may turn more settled in the South in FI. Standard early winter fayre and still no sign of any sustained cold, and probably no snow for the vast majority.

madsnowboarder - thats at least partly because the high over Greenland is a surface one and and not supported with good heights. We need to see the yellows start to appear over Greenland as well. The general upper pattern is not conducive to heights at high latitudes at the moment.