06z model discussions - wet and windy soon?!

[Jude_foster]

What you have to remember though Jude is the GFS is in disagreement with the other models currently. When there much disagreement between each models you have to wonder at the accuracy of all these models even those that are showing what you want. Im not sure any of the models have the correct solution at the moment so it's a case of just viewing more runs until we do find the correct solution.

Worth pointing out about the GFS is that the pattern on the 0Z,06Z was actually shown on some of yesterdays GEFS ensembles but there was far more scatter and this is why the GFS looks to have downgraded because what you saw yesterday was some of the colder ensemble members on the GEFS ensembles atlhough not literally but synoptically.

Lets hope once viewing more runs that the correct solution is for some great snow to fall over the BI.

[Just Before Dawn]

This event is within 4 days now though.

True, but we've had significant changes in the models within 18 hours of the event this winter - the Early winter southerly storm that was progged until 24 hours out and never really happened being the best example I can think of off the top of my head. As I said earlier, we still don't know where this run lies within the ensembles - until then it's all rather academic.

[The Eagle]

I dont think people should be taking any model too seriously atm. Remember the UKMO fax charts at 48hrs even are really different to the GFS and even to an extent the ECM. Another worry that does not seem to have been noticed is that if the UKMO was in anyway certain of its output I would have thought early warnings would already be out. It is possible that the UKMO is completely wrong given both the ECM and GFS output.

However I think over the last year we have seen a marked decrease in the performance of the 3 generally. Im not sure why this is but couldnt possibly go unoticed that looking at 144hrs with any amount of confidence atm is really impossible.

So only 48hrs out and there is disagreement. I doubt the 6z ensembles will shed new light either tbh.

[TEITS]

It maybe worth noting that gfs had light snow for central england for tonight into tomorrow on yesterdays 6z gfs this has now faded into nothing in 24 hours. So it does show how quickly thing's can change.

Not sure why it was predicting that!.

The latest Sat picture shows very clearly the cold front which is currently sitting between Lincs to N Wales and is slowly moving S.

http://www.metoffice.gov.uk/satpics/latest_uk_ir.html

http://www.wetterzentrale.de/pics/bracka.gif

Now note the fronts/trough to the N now they will bring wintry showers to NE Scotland and then towards E Coastal counties later on today. I wouldn't actually be surprised if N Norfolk recieves a few light snow flurries by tomorrow morning.

Certainly going to be cold tonight with mins reaching -6C in places.

[Harsh Climate]

http://212.100.247.145/ensimages/ens.20070.../t850London.png

lol, how people can see an esemble like this and say that the mild/cold battle is in the balance beggars belief!

[Duane S.]

Not sure why it was predicting that!.

The latest Sat picture shows very clearly the cold front which is currently sitting between Lincs to N Wales and is slowly moving S.

http://www.metoffice.gov.uk/satpics/latest_uk_ir.html

http://www.wetterzentrale.de/pics/bracka.gif

Now note the fronts/trough to the N now they will bring wintry showers to NE Scotland and then towards E Coastal counties later on today. I wouldn't actually be surprised if N Norfolk recieves a few light snow flurries by tomorrow morning.

Certainly going to be cold tonight with mins reaching -6C in places.

Well, I really am the eternal optimist but happenings over the past 24 hours have convinced me that this will be a no-show snow event for the south of the UK. Without a half-decent block to the east then even if a short wave does develop and run across the channel there no way of it pulling in any decent cold. Rare for me to say it but for the time being at least, it ain't going to happen.

[January Snowstorm]

Yet another over ramped event.

WIB is about the only one on here who gives realistic forecasts.

The gfs has obvious flaws that are becoming more obvious year by year

[Simon SWales]

http://212.100.247.145/ensimages/ens.20070.../t850London.png

lol, how people can see an esemble like this and say that the mild/cold battle is in the balance beggars belief!

Look interesting mid feb though, almost -15hpa

[The Eagle]

Hi JS, you could not possibly rule anything in or out yet. However your right to be pessimistic because anyone who is getting 'excited' (with the exception of those in Scotland) about the prospects is probrably a little foolish atm as the possibility of a letdown is higher today then it was yesterday.

On balance I think the UKMO is probrably wrong and in the context of the ECM I think the front will be further North and that undercutting depression will probrably not be that obvious. Good to see the ECM backtrack a little bit with better prospects but the GFS with two downgrades in row is really starting to become a thorn in the side this far out. I think if the 12z is the same or worse again then the 6z, then yes, you would have to favour that outcome. However certainly we are none the wiser atm.

[Supercell]

Awoke this morning to an 06z that only further fuels the cynic in me. I am sure many will be disappointed, but it is to be expected these days. The models always bring with them modifications and flaws as T 0 hrs approaches.

[The PIT]

True, but we've had significant changes in the models within 18 hours of the event this winter - the Early winter southerly storm that was progged until 24 hours out and never really happened being the best example I can think of off the top of my head. As I said earlier, we still don't know where this run lies within the ensembles - until then it's all rather academic.

I think you're referring to the Storm that never was. The Storm was removed earlier than that but Meto continued to go on about it even to the point of ignoring there own fax on the day concerned. Twas a fun night though on these forums.

It's rare for models to change this much at such a short time at T60 it's normally pretty well nailed in. Hopefully they'll change back.

[TEITS]

Yet another over ramped event.

WIB is about the only one on here who gives realistic forecasts.

The gfs has obvious flaws that are becoming more obvious year by year

Why is it Friday and has the event already happened.

A realistic forecast for this week would be "Sorry I don't have a clue"!.

What some need to remember is in these situations there are bound to be some locations that miss out whereas others have plenty of snowfall. If you look at these battles between cold vs mild then your location never does well due to being always in the mild side. By what I remember in the past these battles always bought snowfall to Midlands/N England/Scotland but rarely to S England/Ireland and I think this will be the case this time.

[snowmadchrisuk]

I see the Jet wants to trvel back north and back over us by next weekend. A possible cause of the downgrade?

[memories of 63]

Today's o6z is depressingly similar to the charts we had at the beginning of Novembef (can anyone dig these out?) where we had a trio of LP's circling arounf the BI and not really going anywhere. It seems the end of Winter is going to be just like the start.

[Harsh Climate]

http://www.wetterzentrale.de/pics/Rtavn661.png

I think it all goes wrong here when the little channel low/low doesnt develope, this was the cause of the winds turning easterly and maintaining the cold..

Although it would be ignorant to ignore the recent output, there is still allways the chance of the unexpected.

We really need to see a good GFS12z (that redevelopes that small low) and a good ukmo, then things should be back on track.....

[Pennine Ten Foot Drifts]

Yet another over ramped event.

WIB is about the only one on here who gives realistic forecasts.

The gfs has obvious flaws that are becoming more obvious year by year

What is 'ramping' ??? All I have seen over the last few days is people discussing the model output as it has looked at that time, and it is only human nature to respond to that output accordingly. I haven't seen many posts talking about how much snow we were definitely all going to get at any specific time or location - in fact generally speaking it has all been very circumspect.

The fact the models are now showing a different outcome does not make the discussions of the past three days invalid. If individuals have chosen to build up their own hopes too much then that is their own look-out !

Edited February 5, 2007 by Pennine Ten Foot Drifts

[snowingtequila]

What a depressing lot you all are! No analysis of the models in this thread just people going oh dear wasn't it a let down!

[Just Before Dawn]

I think you're referring to the Storm that never was. The Storm was removed earlier than that but Meto continued to go on about it even to the point of ignoring there own fax on the day concerned. Twas a fun night though on these forums.

It's rare for models to change this much at such a short time at T60 it's normally pretty well nailed in. Hopefully they'll change back.

I think you're right upon recollection - the downgrade of that low-pressure system began around T-60 hours but I still remember receiving UKMO fax charts at work up to 48 hours out that still had a LP system of some (though reduced) concern - it then dwindled to nothing as we continued to receive updated warnings.

It was a fun night at work too - much wailing and nashing of teeth.

[The Eagle]

. By what I remember in the past these battles always bought snowfall to Midlands/N England/Scotland but rarely to S England/Ireland and I think this will be the case this time.

TEITIS this is quite wrong from my experience in my location. The charts on the ECM and UKMO are snow charts for us. The GFS is not, well it is for a time but quickly erodes. It is also not as uncommon as that in places as far south as Cork. This time out I still feel confident for the Northern half of the country especially in the midlands (Ireland). So JS is probrably right to be a little disappointed however given the orientation on the GFS of the low snow that far south looks unlikely. Sleet possible though.

[Thundery wintry showers]

http://212.100.247.145/ensimages/ens.20070.../t850London.png

lol, how people can see an esemble like this and say that the mild/cold battle is in the balance beggars belief!

Because those are the GFS ensembles, and the UKMO and ECM both look entirely different to anything on the GFS ensembles.

If the UKMO and ECM fall into line then I see cause for the current Doomsday feeling, but as it stands all this worrying over one run is almost laughable; how do we know that the GFS is right and the UKMO and ECM are wrong? The GFS has certainly changed dramatically, but so has the ECM- which of them have picked up on the right trend, especially given that they're essentially showing what each other showed yesterday?

May be worth checking out the GFS 12Z (the run of the GFS I mainly use) with how its own 12Z was yesterday, and of course seeing if the UKMO and ECM at 12Z fall into line with the GFS.

[yamkin]

Yamkin, its quite a downgrade, and close to the event too......thats a bit more of a worry than upgrades/downgrades in FI.

I notice on every model run you come on and say "more upgrades to come", what do you base this on?

You are basing one model run as a downgrade. I got my fingers burnt badly last year in a matter of speaking regarding info I receive on model outcomes. Sorry if this is not a 'prove it model' response PT.

I'm still positive that we will have a good battle between Cold v Mild this week with wintry showers extending just anywhere.

[johnholmes]

not sure how well this will be received but my latest 'take' is about to come out in blog 8. Its as I see it from the 3 main models this morning, having sat on the fence last night.

It may need another issue later today or tomorrow IF the models change their minds again but I rather doubt it.

enjoy if you can!

[VillagePlank]

lol, how people can see an esemble like this and say that the mild/cold battle is in the balance beggars belief! :lol:

A little bit disingenuious, I feel, and certainly a bit unfair.

A cold/mild battle happens whenever there is a frontal boundary I think that the likelihood for snow happening this week is what is in the balance. Even if that's not what has been said, that is certainly what is meant.

Incidentally, snow shower forecasts (those being caused by convective activity alone from an unstable surface boundary) are always well forecast by the models, and their human counterparts. That is, of course, their existence: the problem in those situations is the distribution of such showers leading to the 'Will it snow in?' Which has it's summer counter-part: 'Will I see lightning in?'

Snow caused by frontal systems is always going to be marginal because a front marks the difference between cold and warm air masses so you are always going to have warm(er) air around. These setups are notoriously hard to to predict; and, as I understand it, there is no notion of numerical certainty that can supply a method to produce a good forecast in marginal situations. I read, somewhere, that the existence of showers is forecast with an accuracy of 75%, and frontal snow, currently stands at 20%.

It may indeed be a case of watch the big picture, let the cold air come in, and see what happens on the day.

In fact, I'm almost certain of it.

Edited February 5, 2007 by VillagePlank

[Snow storm]

Wow UKMO really has a mind of its own.

http://www.wetterzentrale.de/wz/pics/Rukm961.gif

http://www.wetterzentrale.de/wz/pics/Rukm1201.gif

[Harsh Climate]

''but as it stands all this worrying over one run is almost laughable''

Im not baseing it on one run, its the progression from the last few runs that is most worrieng (GFS)...

Also, the Ecmwf has performed poorly this winter and is generally all over the shop (so dont take any heart from that) but as you say, the UKMO is very promising so theres still hope yet.. :lol: