bobbydog

so... to sum up the information at hand so far, we have the NWP showing some fairly decent cold weather on the way. various options of the cold getting to us but mainly from the east, with some form of blocking showing up, scandi, greenland or any combination of the two. however... this is (apparently) without the influence of the SSW which is not showing up in the output as yet. so basically, the wintry weather would have been predicted anyway. now, if an SSW increases the chances of cold in a favourable set-up, then (theoretically), we have that in place already therefore what we should (again theoretically) see are short term upgrades to any cold weather predicted by the models as the data becomes available for input (theoretically) happy days!!

looking at the ensembles, i don't think we're any the wiser really. i couldn't tell you where FI starts but it's no later than +144. we have a shortwave minefield to get through first and after that..... who knows....

aye... but will the weather follow the UKMO........?

its not bad but half an hour after you've looked at it, you want to have another look.....

i take it from that, that the anwer to my earlier question- was 'yes'

that may be the case, but isnt it true that the effect on the troposphere is extremely variable and relatively hard to model, especially at longer range? if that is the case (and i could well be wrong- i'm no expert) would we not be looking at a very dynamic and evolving situation even at short range?

that's the point really, as of now, the models are chugging along as if there is no warming. as the effects become more apparent, the models will change accordingly. theoretically at very short timescale as the situation evolves, therefore even the usual "reliable" timeframe cannot be relied upon.

can i just ask, at what point do the models factor in data from the SSW (which has only just begun today) and in turn, reflect this in their output? does anyone actually know and is this even an answerable question?

great, thanks for that

hi WM, do you have a link to that chart?

to be fair though ian, you can't really compare the 'usual' model output, of which we are all aware of the pitfalls, to the current output. as i'm sure you are aware, we are at the beginning of an SSW which as well as increasing our potential for cold weather and northern blocking, throws a huge amount of uncertainty into the models. i doubt we will see much model agreement until the warming becomes well established. in the meantime, there is some decent agreement in the earlier timeframe for a shot at cold on which the GFS and the ECM both agree- GFS ECM both showing heights over scandi and an easterly at +144

Ian S??

but ian, that chart is at +240 aka FI. it leads to this at +348- your theory is not really too worrying is it.....

i suppose on the positive side, it shows us starkly different ways of being hit by copious amounts of snow!

time for bed after some interesting model viewing- but a word of caution is required - mind you don't slip over in the snow....

well, models looking good so far tonight. i wonder if the real weather agrees with the models.....

i 'can't remember' who used the argument that none of today's output was showing a cold solution, therefore showing a degree of 'agreement' between the models and to be honest it doesn't matter who said it. its just a shame the 12z ECM wasn't out at that point- this chart at +192 might have tempered the mood a little...

maybe the black hole will eventually take the shape of a wardrobe with a gateway to narnia....

EY! EY! calm down!!

i dont see how anyone can be worried by, or have any faith in, any one run at the moment. with ensemble scatter like that, i'll be putting sledge runners on my sun-lounger, to be on the safe side...

not an ideal run steve, but under the circumstances, with the SSW data only just starting to filter into the model output, do you honestly think it will look like that in 6 days time?

hopefully, in ten days time, steves dongle will be frozen......

but this is not a situation we're in 'fairly often'. ian said only yesterday that the Meto's own model is "unconvincing" at t144

IGNORE EVERY RUN FROM EVERY MODEL AFTER 144HRS alternatively, ignore every post from ian ferguson which contains information from a world class professional forecasting organisation....

never go to beachy head with him....