New thread...

Agree with the comments in the previous thread about model accuracy. The outlook isn't looking great at the moment with many model runs showing a cooler north / northwesterly flow across the UK and higher pressure to the west.

The problem is the positioning of this low pressure at the end of next week, which currently is shown hanging around Ireland for a few days then planting itself in the North Sea and dragging down northerlies while the AH sits out in the mid-Atlantic. I'd been hopeful the models would start taking the depression further North and flattening the flow but that's clearly now not happening - it's too late for such a big change. The remaining hope is for the low to dive further South, get cut off and for high pressure to sneak back up on us from the East.

After the flip-flopping there's been in the model output over the past 3-4 days, I don't think that at the moment we can say with any great certainty what things will look like come the end of next week. As Moomin alkuded to last night, anything beyond the middle of the coming week is very much open to question right now, and I don't think it is out of the question that the models could yet change their mind wrt the positioning of the LP later next week.

That's my thinking too; there has been what seems to me like an unusual degree of switching, adjusting, regressing and retrogressing of late. The GFS in particular doesn't seem to stick to its guns for long.

I think the way the general pattern is being forecast this morning (just going by the ECM) that the GFS, which in previous runs had a relatively more mobile regime taking hold in the medium term, seems to have been more on the ball generally speaking.

I am sure, like many others, that the first port of call for me regarding NWP forecasts is the ECM; but lately I have started to question whether the ECM really is all that much better than the GFS in its ten day outlooks?

From what I've read here this summer, it seems the models don't want to us to have a good summer and only reluctantly show good weather when it's imminent. 

I have been hoping that the Azores High would finally move in and sit either over us or just to the south and give a spell of 4 to 6 weeks of warm and sunny weather.

Seems like from latest comments that will elude us sadly.

Must have missed this from further up the page:

"The models are ALWAYS "flip flopping" and showing uncertainty - this pretty much happens 52 weeks of the year, not just high summer or mid winter and it is why MO beyond 3/4 days is fruitless task. There is no such thing as output being nailed on. It's always pots of gold at the end of the rainbow, or in our case, stepping in cowpats on the path to chasing that elusive pot."

The latest GFS proves my point (or, rather, DMPs point) about GFS- the low at the 7-10 day range now slips south and fills enough to allow warm uppers further NW in Europe, and by day 11 this starts to advect in a NEly towards the UK.

By day 12 http://www.theweatheroutlook.com/twodata/chart.aspx?chart=/charts/gfs/06_288_mslp850.png?cb=649

there is a brisk NEly with a low just to the east of us, in 10C+ uppers. This warmth consolidates over the following couple of days.

Now I'm not naïve enough to think this is what will happen at this range; nor would I entrust the 00z run any more at this range. But I certainly wouldn't be casting my line out into the mid-stream of mid-summer. The main point is, that if the GFS makes changes like this on a 6-hourly scale, why are the lamentations coming out because of the recent threat of a Scandi low setting up into FI?

Looks pretty likely that a cyclone will be within close proximity to the UK later this week, however with such a slack pattern I'm hoping a few more twists can come....

If that cyclone can get stuck to our west...

I'm absolutely furious with the 12z GFS op.

So, so annoying. 

:-( 

A brief warm spell before some potentially very unsettled conditions. The low wants to stick to the UK like a limpet. 

It looked so, so good! 

Even those in the south manage to join in the party this time. 

http://old.wetterzentrale.de/pics/Rtavn1684.gif

Just lovely. 

Yep. Bit of rain for the gardens, then back to decent sunny spells I reckon.

http://www.theweatheroutlook.com/twodata/chart.aspx?chart=/charts/gefs/gefsens850london0.png?cb=327

That's just hedging. Come on, the start of the chart is up and down, and even in a less up-and-down jet set-up you don't get a flatline for that long. Surely it's obvious that the nearer to now, the more undulating the models predict? That's because undulating is the reality, and clustering at FI is a fantasy. I think I might just get a KS1 pupil to predict the 10-15 day line with some different colours, thin paint brushes. I bet it would be nearer the delivered outcome.

ECM looking fairly decent next Friday: HP ridging close to south coast, lp over Iceland

and by next Saturday could be settling down nicely in the S. I feel the ECM has got this about right, time will tell.

One wonders if some kind of pattern change may be afoot, Kieren. I have seen people comment in here in the past that sometimes the models struggle a lot, including the normally trusted ones, if they are picking up the beginnings of a change in pattern.

One thing is for sure, which is that after all the volte-faces we have seen in the past week alone, I'm taking the output with a rather larger pinch of salt that I would do normally, and I'd advise all regular followers of the output to do likewise if they want to retain their sanity!

Good to see that the 12z ECM is WAY better