Model Output Discussion:

[SP1986]

Right now due to the current set up the science of weather modeling is virtually impossible - If you look further than about 24 - 48 hours you are probably wasting your time cause it'll all be different on the next set!

To be honest despite the latest twists and turns I can't really see any else other than either a southeasterly, southerly or southwesterly happening, it's which one that's the question. The majority of the ensembles favour a southwesterly, and to be fair perhaps this is more likely in the near term, but there's no reason why an easterly won't setup in the medium term.

As someone said a few days ago, It'll probably end up taking the 'middle of the road' approach, rather than the two extremes that have been predicted in the models over the past week.

[aspire27]

As the models flip from one output to another the only consistant theme is the METO. They are still going for a cold period coming up and have not back tracked one bit as far as I can see.

Am I correct in saying this?

Due to the poor models (i dont mean for cold, or for mild) I think the experience and human touch of the professionals with their science over at the METO will be interesting to watch.

I think the METO are still against a mild outlook.

Anyone agree?

EDIT:

Wasnt lasts nights fax very different to the model output also?

Edited February 2, 2010 by aspire27

[Bobby]

GFS Op mean at +180

http://91.121.94.83/modeles/gens/run/gens-21-1-180.png?6

GFS Parallel mean at +180

http://91.121.94.83/modeles/gensp/run/gens-21-1-180.png?6

Paralell mean is better, more of an easterly flow, and as the parallel is the new upgraded ensembles it should be better.

Edited February 2, 2010 by Barb-

[karyo]

An unfavourable development from the MJO! It has now moved back westwards to Phase 6! We need it to get towards phase 8 (east of the dateline)!

Karyo

[No Balls Like Snow Balls]

The GEFS 06z control at T180 is virtually a carbon copy of the ECM 12z at T216

[nick sussex]

Looking at the UKMO further outlook in relation to the models that implies shortwave energy disrupting from troughing to the west and heading se'wards with high pressure to the ne. If we look at the models even the ones not following the UKMO a small change to the tilt of the jet would provide this scenario.

So its a plausible forecast by them, key areas to look at this evening are what happens to the shortwave near northern Norway and how far north the main upper trough is in the Atlantic.

[yamkin]

An unfavourable development from the MJO! It has now moved back westwards to Phase 6! We need it to get towards phase 8 (east of the dateline)!

Karyo

The ensemble members (yellow lines) and the ensemble mean (green line) are hovering between Phases 7 & 8 IMO. Please correct me if I'm wrong.

Edited February 2, 2010 by yamkin

[karyo]

The ensemble members (yellow lines) and the ensemble mean (green line) are hovering between Phases 7 & 8 IMO. Please correct me if I'm wrong.

I forgot to post the link showing the current state of the MJO: http://cawcr.gov.au/bmrc/clfor/cfstaff/matw/maproom/RMM/phase.Last40days.gif

As you can see, it has now gone back to Phase 6. Your link shows the forecast and it is good to see it is still expected to head for Phase 8 soon. However, the MJO forecasts are extremely unreliable so I always tend to focus on the current state rather than the predictions.

Karyo

[yamkin]

I forgot to post the link showing the current state of the MJO: http://cawcr.gov.au/bmrc/clfor/cfstaff/matw/maproom/RMM/phase.Last40days.gif

As you can see, it has now gone back to Phase 6. Your link shows the forecast and it is good to see it is still expected to head for Phase 8 soon. However, the MJO forecasts are extremely unreliable so I always tend to focus on the current state rather than the predictions.

Karyo

Thanks karyo. Do you know what phase(s) the MJO was in during the very cold periods in December 2009 and January 2010?

[karyo]

Thanks karyo. Do you know what phase(s) the MJO was in during the very cold periods in December 2009 and January 2010?

It went to Phase 8 for a time on both occassions, at least for a time.

Karyo

[Guest North Sea Snow Convection]

The MJO 'like other factors, is not the be all and end all on its own. There is actually an argument, I would propose, to suggest that if it doesn't progress too quickly it might help cement a cold spell in terms of allowing time for the downwelling of the warm stratosphere negative anomalies right down to the lowest layers of the troposphere. There is an issue in terms of this happening soon enough to coincide with the other factors like the MJO and GWO orbits. On that basis slightly later timing of the MJO to the dateline would perhaps be most especially effective in terms of assisting solid northern blocking that might be less transistory and with the best chance of being in a favourable location for the UK.

We will have to keep watching the modelling but a delay of a day or two, might not be a bad price to pay (only if it happens of course) in terms of ensuring that the next cold pattern when it arrives is more durable.

Edited February 2, 2010 by North Sea Snow Convection

[nick sussex]

All eyes towards the shortwave near Norway, we want this weakened and pushed east to allow better ridging from the NE, this will allow a better jet tilt to the lows approaching.

[nick sussex]

Not playing ball again nick.

GFS is not going to back down,ukmo will surely have to now?

Its the shortwave that appears later,that current shortwave is modelled even by the UKMO.Its around the 96hrs mark onwards. Crucial time coming up, the shortwave ejecting from the trough needs to clear se without leaving any energy behind, we want a clean break here.Unfortunately this looks a poor run, I would go to plan B but thats already out of the window! I can't even think of a plan C!

Edited February 2, 2010 by nick sussex

[Shunter]

I forgot to post the link showing the current state of the MJO: http://cawcr.gov.au/bmrc/clfor/cfstaff/matw/maproom/RMM/phase.Last40days.gif

As you can see, it has now gone back to Phase 6. Your link shows the forecast and it is good to see it is still expected to head for Phase 8 soon. However, the MJO forecasts are extremely unreliable so I always tend to focus on the current state rather than the predictions.

Karyo

Totally agree, I cannot EVER recall the MJO forecast veryfing, its always incorrect just a question of how much !!

[Cecil Hogmanay Melchett]

Too much energy off the atantic and that blinkin azores high is ridging NE meaning the energy is moving NE.

I hope im wrong but it doesnt look like a backdown from gfs to me?

[BurwellWeatherWatch]

GFS not looking too great for coldies ATM but don't think ukmo is going to back down tonight if indeed at all. Would be good to get some consensus from ECM though too

[Bobby]

Awful GFS.

It's not backed down because it wasn't supporting it in the first place...

[nick sussex]

The UKMO is not as good as this morning at 96hrs but still holds the upper trough energy much further west.

[cooling climate]

The UKMO is not as good as this morning at 96hrs but still holds the upper trough energy much further west.

Have to disagree there having just looked at this mornings t96 on wetterzentrale.

[nick sussex]

Not what i wanted to hear nick,any sort of backtrack from ukmo is bad news for an Easterly.

Unfortunately I think we've come to the end of the road here, without the shortwave cutting se'wards its all downhill from there. By the time the upper trough starts to weaken its too late as theres nothing to stop it moving ne wards and this elongates into a poorly tilted trough. It looks like a western based negative NAO with high pressure to the se. A pretty horrible looking 144hrs UKMO, a Freddy Kruger special!

Edited February 2, 2010 by nick sussex

[The Weather Dragon]

West based negative NAO becoming established - mild S/SW for us - block is diminishing to the East. Welcome to a mild & wet February.

[Mark Bayley]

UKMO is not as good as this morning, and seems to have trended towards the GFS with winds from the South/South West. Awaiting the T144 chart now. Will be interesting to see what the ECM does. Not looking good though! Still, it fits in with the teleconnection forecast. a -NAO and -AO, the NAO being west based.

T144 chart out, no easterly with the winds from the South West instead, doesn't look to mild to my eyes. But certainly not cold

Edited February 2, 2010 by mark bayley

[Bobby]

And the UKMO +144 is the final nail in the coffin.

Just watch the ECM pull out a stunner now, lol.

[nick sussex]

The Norwegian shortwave plays its role here in causing the poor output, this feature stops a better ridge from the NE, unfortunately remnants of the Scandi trough refused to leave that region and this is at the end of the day what caused the no show easterly fiasco of last week and also the disappointing evenings output so far.

If the models finally agree on this outcome then its a long road back to cold with that elongated troughing to the nw.

Edited February 2, 2010 by nick sussex

[Thundery wintry showers]

There is still an outside chance of this easterly coming off in a week's time IMHO, but only an outside one. The Atlantic is proving a bit strong, and we do look headed towards a January 1969 style blocked setup with blocking in the right places to bring mild south-westerlies to the British Isles- probably a cloudy wet mild spell coming up, even though many of us may not want it.

However it continues to be the case that towards a week's time we still have the jet on quite a southerly track and reasonably high pressure around Greenland/Iceland. I think this may give us a brief cold shot from the N or NE towards midmonth.