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Nick has written an in depth synoptic analysis blog, looking at the active and potentially stormy weather this weekend. http://www.netweather.tv/index.cgi?action=news;storyid=7246;sess=

The past three GFS runs for Friday 25th, in chronological order: The theme of height rises near Scandinavia was already picked up on a couple of days ago, but with the undercut of the jet taken too far. This has since been refined, with the idea of that high retrogressing being put back in time. In terms of the airmass, we have tended to be near or on the boundary between unseasonably warm air to the south, and rather cold air to the north. Now the same treatment with the ECM output: The upgrade a few weeks back doesn't seem to have helped the model out in this situation - assuming the Scandi height rises do turn out to be the way forward. The disruption of the troughs as the jet heads down into Europe has taken until today to be captured. It's an interesting setup, and all the more so when there is no attempt to flatten the high in the 9-10 day range such as GFS goes for. In this respect the 12z GFS seems to be a bit of a rouge run, with previous runs keeping the high at higher latitudes and maintaining the potential for both warm incursions from the S/SE and cold incursions from the N/NE. Notable is the lack of westerly components to those possibilities.

Gfs op and para have been keen on the height rise to our north/northeast in week 2 for quite a while. For one run at least, ECM op comes on board.

ECM going for a distinctly chilly start to April.

Not more 'potential'? I haven't yet managed to dig myself out of last winter's 'potential', yet!

I'll be saving hard for both

My EX is called katie. If its anything as bad as her, hold on to your hats!

Yes, it looks like the SE will get battered by some quite dangerous winds on Monday sadly Plenty of rain too. Must be a Bank Holiday?!

Any chance of it turning to snow on its northern edge

The uncertainty in the models and the Fax charts remains this morning. All now seem to have decided against any possibility of it staying south over northern France. The idea of it exiting somewhere between the Humber and the Thames estuary that seemed favourite yesterday has been shift by all 3 main models to north of the Humber, currently around Newcastle looking the most likely. The T_84 Fax chart issues by Met at 0547 this morning gives their latest ideas. Just north of the Humber centre 969mb from its value of 1001mb on Sunday 00Z around 47N32W, so a fair amount of deepening expected. This helps turn it left of its track and looks okay looking at the 300mb predicted flow with it embedded in the jet and exiting in what looks like the left exit region.

Not sure how much we can trust any particular model at the moment, but the GFS-based 2m anomaly maps for days 6-10 and 11-15 caught my eye on tropicaltidbits.com; Amazing that the U.S. is the only continent with notably below average conditions affecting more than a % or two of the landmass. Essentially, all of the cold air ends up focused over the U.S., as yet another major cold wave (relative to average) affects the region. Many recent winters have featured such events - for some reason the polar heights have been tending to align in a way which favours such a thing, though usually there is an export to the Asian side too, which is notably lacking this time around. Conditions are looking pretty crazy at the other end of the scale across most of North Africa by the 11-16 day period. Such a widespread early build of heat puts me on European heatwave alert for late spring and the summer, not so much in terms of their likelihood but their potential severity should the broad scale pattern allow them in the first place. Yet even that can't compare with the anomalies shown over Greenland, which are a reflection of the idea of height rises in the vicinity of Scandinavia which then slowly retrogress, this being something GFS/GEFS seem very keen on while ECM has not really been there but appears to have moved toward to some extent with the 12z effort. I'm not sure, but this might be just about the worst case scenario for the Arctic sea ice during the first 10-14 days of the melt season. By exporting so much cold air to just the one region at this time of year, the door is left open for imports from a generally well above average rest of the N. hemisphere landmass. Meanwhile there are interesting implications for the UK; there is an abundance of unseasonably warm air to tap into, which means that an exceptionally warm day (e.g. mid-20's across a wide area of the south) is a lot more achievable than unusual. It just needs the right alignment of the troughs and ridges ahead of the retrogression of that Scandi High- assuming such even comes around; the models (both det. runs and ensembles) have seemed a bit too keen with that sort of thing over the past few months. If it does happen though, we could see both a date record maximum and a date record minimum in the same month. I believe such a thing has actually happened quite recently - in July last year?

Comparing past winter with the last super nino winter of 97/98, we see ho much stronger the eastern nino regions were in 97/98. we can also see how this winter we had much cooler Atlantic, from the tropics all up to the north. And if we look at March so far, last 23 days mean, we see the Atlantic difference even more, with a very "-AMOish" signal appearing when comparing it to 1998. But it is also generally cooler north of tropics when compared to last year. And March so far this year. And last 7 days of March versus first 7 days. we can see SSTs have cooled off a bit north of tropics. But what stands out the most is the typical positive IOD phase signature.

Storm Katie is the latest named storm, this time named by the Met Office. It's due to arrive late Easter Sunday and into Easter Monday with the main impacts, expected to affect southern Britain. More info here: http://www.netweather.tv/index.cgi?action=news;storyid=7247;sess= And excellent blog here by Nick, with an in depth look at the synoptic setup this weekend. http://www.netweather.tv/index.cgi?action=news;storyid=7246

If only we would keep BST all the year round?

It could well be short-lived in that setup though, ECM also shows quite a dramatic shift to warm conditions by the Sunday.

Yes Blue the Scandi. heights starting to show from around days 8/9 on both this evening and supported by the GFS mean. It looks like after the Easter low fest the Atlantic stalls out west as pressure rises towards the end of the week.Maybe a few days of drier easterlies with some sunshine but again the N.Sea cloud could be a problem depending on the exact surface wind direction.

https://www.netweather.tv/forum/blogs/entry/4927-alps-ski-and-snow-forecast-blog-issued-25-march-2016/ The latest Ski Blog has now been completed for the Easter weekend. A good Easter seems likely on the slopes, after this fronts pushing in from the west with snow on higher slopes, and at times on lower slopes. Thereafter a battle between cold to the north and very mild to the south, some indications that the mild will win out, especially for southern parts of the Alps. But a lot of uncertainty.

Here Comes La Niña--Or Does It? What History, Models, and Experts Tell Us https://www.wunderground.com/blog/JeffMasters/here-comes-la-niaor-does-it-what-history-models-and-experts-tel

You may well be right Daniel. This afternoon's NMM and Arpege output, whilst differing in timing, both have some very, very strong wind gusts for the South coast. With NMM now in range it's supporting yesterday's Arpege forecast of 120 km/h (75 mph). But today's forecast from Arpege is worrying, with what looks like gusts of 150 km/h (93 mph)!! NMM Mon 05.00 Arpege Mon 08.00

Already have both set in our sights to do. If you take the eclipse you could also do a lightning session in Arizona, what a great way to enjoy, eclipse plus lightning, mmm mm... It is possible to get from the eclipse path with a couple of days driving into Arizona for the lightning & haboob season, thus making it a great visit.

It's a shame the blog does not offer a 'like' option - that is definitely a post worthy of up votes. Edit to add .... 06Z Arpege takes the low in a little bit further north - nasty swathe of gust potential on the southern coast.

5.4c to the 24th 0.1c below the 61 to 90 average 1.0c below the 81 to 10 average

I wonder if the Met office will give this low a name even if we are now no longer in winter. Looks to have the potential for nasty impacts on a densely populated area in the middle of the day. Talking of winter, probably as well that the winter crew have departed - how frustrating to see synoptics as shown in the low-res GFS. ... the long awaited effects of the MMW (or is it now classed as the final warming) are being seen at last.

Well the sky is completely clear of cloud, it should be a mostly sunny and pleasant day. Well one out of 4 isn't bad.....

I can't see it going there looking at the predicted T+96 on all 3 models. Looking at the 500mb flow, as it is now, also the Fax chart showing it at 987mb and the direction of the warm sector isobars. All suggest it somewhere over E/SE England during Monday. Hard to say where it will exit into the N Sea, anwyhere between the Humber and Thames estuary is the best I could suggest at the moment. As with most lows the worst winds will probably occur in its SW sector. An interesting forecast dilemma for another 24 hours maybe 36 or so?

It's still the outsider, but the GFS has once again pulled a spring-like scenario out of the general pattern in its latter stages:

Yellow Alert of Wind for Wales Yellow Alert of Wind for Wales : Isle of Anglesey, Flintshire, Gwynedd, Powys, Wrexham, Carmarthenshire, Ceredigion, Pembrokeshire, Blaenau Gwent, Bridgend, Caerphilly, Merthyr Tydfil, Monmouthshire, Neath Port Talbot, Rhonnda Cynon Taff, Swansea, Torfaen, Vale of Glamorgan, Cardiff, Newport, Denbighshire & Conwy valid from 0600 Sat 26 Mar to 2100 Sat 26 Mar

Minimum today is 5.0C, while maxima look like reaching the high 9s, so an increase to 5.3C is likely on tomorrows update. After that, the 06z GFS has the CET at: 5.4C to the 24th (6.8: -0.6) 5.5C to the 25th (8.3: +1.0) 5.6C to the 26th (8.9: +1.7) 5.7C to the 27th (7.7: +0.6) 5.8C to the 28th (8.6: +1.4) 5.9C to the 29th (8.2: +1.0) 5.9C to the 30th (7.5: -0.1) 5.9C to the 31st (5.9: -2.1) A finish of between 5.5C and 6.3C is now likely before corrections, and 5.1C to 6.3C after corrections.

Mechanisms determining the winter atmospheric response to the Atlantic overturning circulation http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0326.1?af=R

Gower, Swansea