Model Output Discussion 30/06/2012

[shedhead]

Nice ECM run this morning, it eventually brings the ridge to the east of us!

Angular momentum has stalled, however the rise alone should help reduce heights to our north. The GWO has backtracked into phase 2, heading for phase 1, not great for longer term prospects and the MJO is in phase 2 heading for it's central core.

The mixup of these elements show a mixed August yet again but if angular momentum can maintain its levels and perhaps rise a tad then maybe some better weather will be experienced at times.

Agreed. Looking at the overnight data I think there is now very good grounds for optimism that things are going to improve significantly into the 4th week of July, with Summer finally set to show it's hand, especially across England and Wales. However, there is now a major question mark arrising over whether this change will represent the start of a protracted spell of better weather, or will it just be a blip in the overall pattern, with more unsettled conditions returning in late July/early Aug. Personally I'd love to think it's the former, but given the points you've highlighted re the GWO and MJO, along with the signals coming from the 500mb anomoly charts I'd suggest the latter currently looks more likely - tho just how unsettled it becomes again looks very unclear.

Edited July 16, 2012 by shedhead

[Summer Sun]

Nice ECM this morning its ensemble run gives it support as well

[tinybill]

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=204

morning from now to deep FW to me there no sign of summer , now you read in the paper the the beach volley ball girls will might have to cover up ,can the weather get any worse

[Methuselah]

http://www.meteociel...?mode=2&ech=204

morning from now to deep FW to me there no sign of summer , now you read in the paper the the beach volley ball girls will might have to cover up ,can the weather get any worse

What's 'FW'?

[shedhead]

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=204

morning from now to deep FW to me there no sign of summer , now you read in the paper the the beach volley ball girls will might have to cover up ,can the weather get any worse

Taking GFS in isolation I suppose it's hard to argue. The model that was pushing Summer the farthest north across the UK is now the one effectively keeping it down over France. ECM does look considerably better tho and I think few would conclude that their 240hrs chart is not a decent one for Summer weather, but whether it ultimately verifies of course is another matter altogether.

Edited July 16, 2012 by shedhead

[tinybill]

What's 'FW'?

fantasy world

[AWD]

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=204

morning from now to deep FW to me there no sign of summer , now you read in the paper the the beach volley ball girls will might have to cover up ,can the weather get any worse

I think we need two different threads. One for what the models actually show and one for what people with glazed eyes and humps of negativity think they show.

All 3 models show much welcomed improved weather from this weekend onwards. This weekend will be predominantly dry in the south with warm temps. Battle north does remain unsettled a little longer.

Next week looks like the best week of summer proper so far. Plenty of dry, respectfully warm weather around, and good sunny spells. Yes, the far north is still prone to rainbands around the HP, but that's about it.

Even into FI, whilst it may turn a tad more unsettled, it's nothing compared to what we have endured so far. Still plenty of dry interludes between any rain, these longest in the South, and even a very warm day or two mixed in. I wouldn't rule out rain at the Olympics yet, as there is still well over a week to go, but it is looking like there will be more sun than rain at this stage.

No heatwave, but some very welcome British summery weather is on its way.

[valledym]

Is it me? (I do hope it is) but has the GFS gone 'off on one' this morning promoting a more Southerly Jet and the continuation of more unsettled weather?

The ECM still holds firm with a significant improvement post weekend and into the following week, but as I say the GFS is having none of it?

Would be interesting to hear peoples view on this and whether this could just be a blip by the GFS or could it be onto something? Let's hope not, as I for one am enjoying seeing those deep reds infiltrating our shores!

[forecaster]

The ECMWF deterministic at +10 days looks good with the omega situation developing near the UK, but the ensemble mean is much blander as you would expect at such timeframe, so I wouldn't get too excited yet.

The surface patterns both suggest decent weather over the British Isles, but the deterministic is the only one that has potential for proper warmth.

[Bobby]

NAEFS has the blue anomalies returning towards the end of the month with blocking over Greenland returning too

[shedhead]

Unable to post charts atm, but the 06 GFS has an interesting evolution between T+96-120hrs, with LP now shown to bring heavy rain to the southern half of England and Wales. Is this the start of what might prove to be a model sea change for the weekend?

[Backtrack]

BBQ anyone?

ECM gives a heatwave in a week's time.

[Bobby]

Unable to post charts atm, but the 06 GFS has an interesting evolution between T+96-120hrs, with LP now shown to bring heavy rain to the southern half of England and Wales. Is this the start of what might prove to be a model sea change for the weekend?

Some of the ensembles have been showing this feature lately, ie

[Frank Trough]

Some of the ensembles have been showing this feature lately, ie

....i would take the wash out saturday for a better sunday and for what the 06z then goes on to show - much more postive in the mid/long term and more akin to the ECM this morning.

it's the 06z remember - in winter we would be told not to worry too much, wouldn't we?! let's see where it all sits in the ensembles. Frankly, i won't worry about that low for the weekend until the UKMO shows it, though.

[shedhead]

....i would take the wash out saturday for a better sunday and for what the 06z then goes on to show - much more postive in the mid/long term and more akin to the ECM this morning.

it's the 06z remember - in winter we would be told not to worry too much, wouldn't we?! let's see where it all sits in the ensembles. Frankly, i won't worry about that low for the weekend until the UKMO shows it, though.

I wouldn't, I'm off to the Oval...

[Robbie Garrett]

Even August is looking mighty fine.. for once!!

[Milhouse]

A mere 2 out of the 20 ensemble members for the 0z showed the low for southern England on Saturday. The 6z op obviously is one of those members that choose to pick up on this little feature. It has not been shown by any other model at all and only now its appeared on the GFS. I do not think its cause for concern.

[shedhead]

Even August is looking mighty fine.. for once!!

Depends what chart you choose to look at really.

[Bobby]

A mere 2 out of the 20 ensemble members for the 0z showed the low for southern England on Saturday. The 6z op obviously is one of those members that choose to pick up on this little feature. It has not been shown by any other model at all and only now its appeared on the GFS. I do not think its cause for concern.

Looking at the 06z a lot more members go for this feature, maybe 1/3 now.

Shows up on the precip mean nicely

[Robbie Garrett]

Depends what chart you choose to look at really.

Doom and gloom or Summers Bloom!

To have a fairly decent blue hot summers day in August will be pretty impressive IMHO compared to the last 6...., maybe 9 years.

[Weather Boy]

Some of the ensembles have been showing this feature lately, ie

I find the 6z somewhat puzzling to pick out this feature for Saturday that has never been picked up before and is absent from the other models (although the UKMO does have a little kink in it that suggests that there is almost something there on Friday, but it's gone by Saturday).

Given those two factors plus, as Milhouse says, the lack of support from ensembles, I would be inclined to think that it's most unlikely to verify, but if it persists with it in coming runs, I may have cause to doubt that.

Oddly, thereafter, the models are as one in giving us a fine spell for at least a number of days, it's just very odd that the GFS 6z seems to want to give southern parts a bad day on Saturday before falling in line with the other models which I think would see most with good weather from as early as Friday.

[Thundery wintry showers]

Indeed, I've noticed this little low on the GFS 06Z for Friday/Saturday. If it doesn't materialise we have a straightforward case of sunny intervals and progressively declining shower activity between Thursday and Saturday, and with light winds probably feeling warm in the sun though cool out of it. If it does, some central and southern parts may end up cloudy with some light rain.

My feeling is that we probably will get a little shortwave but that the GFS is overdoing it somewhat- we might just get a little feature drifting along the English Channel perhaps leaving the vast majority of the country with sunny intervals and declining shower activity.

For those looking for a few days to a week of warm dry sunny weather with largely clear skies, you can't really get much better than the last few frames of the ECMWF operational run, and the ensemble mean is quite similar. A brief tropical maritime incursion brings relatively cloudy anticyclonic type weather on Sunday/Monday but then a brief polar maritime incursion on Tuesday is followed by a stronger build of pressure, and an anticyclone breaks off from the main Azores high and settles in the North Sea allowing drier, stable continental air in from the SE. I recall that this particular synoptic progression was a common feature of summer 1996, leading into the anticyclonic spells which hit around the middle part of all three summer months. The GFS doesn't look quite as clear-cut into FI, highlighting the fact that we can't take the above for granted at this range, but the evolution is entirely plausible.

[camiscool]

Is it just me or are the metoffice incredibly bias towards the GFS?

[nick sussex]

The ECM seems to be developing a western based negative NAO at 240hrs, now this can get a bit dicy but also can bring some hot conditions, it really depends where any troughing sets up.

This is the first operational run that its going for the likely hot variety so we best wait and see if this trend develops further.

[Alex]

Is it just me or are the metoffice incredibly bias towards the GFS?

No just being careful with the Olympics coming up, they only really use the GFS for reference and mainly use the ECM and MET models.

I would add caution to the medium/long term as the teleconnections aren't that impressive as I described above.