DaBrigg

Ive been lurking here, reading all the arguments on both sides. As I see it... (from an IMBY perspective in Eastern Ireland). ... the deep cold has been pushed back 48hours now from what the earliest runs were suggesting..still outside the reliable time frame. ..there are now higher 850temps progged for Monday than Saturday!! ..thickness are struggling to get down below 520 this far west until well into fantasy island, they remain fairly high through Tuesday, whereas sub 510dam air had been forecasted on many model runs. Those who are afraid of further downgrades have every right to be concerned. Its not a case of being spoilt after such amazing runs. It looks increasingly underwhelming from where Im sitting.

Suddenly there's lots of lightning and loud thunder from a cell about 10-15 miles east of the Dublin coast, came out of nowehere

Dew Points are hitting a muggy 18C around Dublin, with sunny breaks and southerly winds gusting to 30mph. Temp has been hovering around 23C for hours now. The rain from the cold front is less than 20 miles to my NW.

I know people are desperate for any sort of warmth, but heat from such a deep tropical Atlantic source could be quite horrible. High dewpoints, sticky nights, and the potential for lots of cloud. That sort of weather just makes everyone cranky and irritable, and as an athlete I find it disgusting. I

Over the last hour the remnants of this afternoon's storms that affected eastern Ireland have now flared up along the mid-Wales coast around Cardigan Bay. Some bright echoes, in there too. Quite unusual to see that happening at this time of year.

Just had a surprisingly electrically active thunderstorm, preceded by a gust front, here on the east coast of Ireland, 20 miles north of Dublin. It was very active until i whipped the camera out and started recording, there was no more lightning after that. Its been the first decent storm at this location since the convective Irish Sea thundersnow of late Nov 2010, in fact.

The continental air is now expected to brush eastern Ireland as early as Sunday Night. As the cold is closer to the surface than we're used to, we should pay more attention to temps at the 925hPa or 950hPa level, and the 850-1000hPa thicknesses. If the front stalls just a little further west it could get very interesting for some lucky people. http://expert-images...013000_2712.gif http://expert-images...013000_2712.gif

We also had a light but unexpected fall of snow that morning on the east coast of Ireland. A showery band of precipitation moved south around around dawn, after a hard frost, and landed on frozen surfaces. The covering only lasted a few hours but was perfectly timed to cause trouble during morning rush hour in Dublin, etc. Although it wasn't much, any snow covering here is highly unusual most winters. Funnily enough, I have an Irish TV weather forecast from the previous evening recorded on video.... predicting showery rain, with perhaps a bit of high ground sleet/snow mixed in. The snow was a nice surprise. Conditions were just on the right side of marginal.

I rarely post, but the latest developments in the models interest me. We should all keep in mind just how badly the models seem to handle blocking to our NE. Even if the overall pattern change is picked up well in advance, the models have been notorious for backtracking or changing the western and southern limits of the cold as late t+72 hours. The infamous scenario of frigid air ending up in Greece, seemed to happen all-to-often a few years back. The Arctic high ridging southward into Scandi around t+168 is an unusual pattern, rather like January 1987. It's very rare for such a scenario to deliver the goods here. Many easterlies have tended to come about from the text-book Russian high building westward, and some less potent easterlies even began with a mild mid-latitude or Atlantic high eventually drifting into Scandi. Whatever happens, a pattern change from the relentless wind and damp that we've had for weeks seems very likely to me. I've been keeping an eye on the SSW thread, keep up the good work guys.

We cant take too much notice of just one run, so speaking strictly hypothetically.... if the 18z came to pass, North Sea coasts would get a nasty back edge NW'ly, while the Channel still gets a tight SWly gradient as the storm passes to the north. It looks like Cornwall would get worse winds with this scenario. http://www.wetterzentrale.de/pics/Rtavn969.png http://www.wetterzentrale.de/pics/Rtavn1029.png http://www.wetterzentrale.de/pics/Rtavn1089.png

The 18z isnt a downgrade for some, the low still bombs, just later. It drops 20mb in six hours as it moves into the North Sea. It shouldn't be dismissed just yet.

The 18z has the secondary low centre from Tuesday's storm further south and west, bringing a second batch of strong winds into Ireland then Northern England instead of Scotland on Wednesday. Quiet a difference for some of us at only t+60.

One thing to note about the ECM enembles, most of them seem keen to keep the low centre in whatever form it comes reasonably far south. None at all throw it north of Scotland completely. There has been a slight southward shift over the last few GFS runs as well, I believe.

That was one ensemble member.

Meanspeeds at 10m above ground level, but the GFS may be overdoing it a little. Model run after model run shows the possibility an exceptional wind event. If highlighting what the charts actually show is considered hyping and ramping, so be it! What else can we do, bury our heads in the sand and ignore them? Most of us realize the track and intensity of the storm is subject to change, but it doesnt mean we cant discuss what the charts actuallly show right now!

Midnight Friday, parts of Northern Ireland lie under near calm conditions, while hurricane force 12 winds, in excess of 80mph sustained, covers a large swathe of the Irish Sea. Unbelievable. Northwest Wales gets clobbered.

I sometimes feel that storm is a little overhyped. For a relatively small area in the south of Ireland it was a rare event, but perhaps not quite as rare as it is often made out to be. It was a compact storm that hit out of the blue in the middle of an important afternoon, so will live down in memory. A short lived squall accompanying a cold front on Christmas Eve 1999 delivered stronger winds to the Dublin area. If, and thats a big if, some of the models verify, some places could easily experience the worst winds in living memory. We shall see.

Yesterday morning's ECM also had a very compact storm, with extreme winds over a smaller area, taking a similar similar track across the northern fringes of Ireland and into Central Scotland. Long time model watchers like myself are used to seeing the GFS occasionally overdoing storms at his timeframe, only to tone them down a little closer to the event, but this consistency from the ECM, along with reasonable agreement from the UKMet, is worrying. (or promising, depending on your viewpoint). Incidentally, Ive only just noticed those weatheronline charts apparently don't show pressures lower than 950hpa, perhaps I'm a little slow.

Fascinating. I have often seen those charts used in tropical weather forums. At least some of the energy behind this potential storm can be traced right back to the deep tropics.The low that eventually spawns the Thursday/Friday storm develops near Bermuda around Tuesday, feeding off a plume of deep tropical moisture, which from reading the forums on storm2k, appears to have produced nasty flooding rains in Puerto Rico and the north east Caribbean over the last couple of days. Bermuda weather service decribes this feature: http://www.weather.b...licExtended.asp Of course, its only when this gets into the jet stream and interacts with the cold air flooding out of Newfoundland that we get our explosive deepening.

My family must think I'm nuts, considering the expletives ive just been shouting at the PC. As others have echoed, by far the strongest winds I have seen (on the GFS at least). 18z GFS has 850hpa winds at Dublin airport at 21z on thursday hitting 135mph, with Liverpool and Manchester hitting around 125mph, 3 hours later (bear in mind the 850hpa level is down to below 1000m close to the storm centre, so the mountains in Snowdonia would easily hit these windspeeds, sustained! Dublin Airport: http://wxweb.meteost...0&submit=submit Liverpool: http://wxweb.meteost...1&submit=submit

Well, well! The 18z seems to have the second storm arriving 6-12 hours earlier, and as a result is further south! The worst winds now arrive in western Ireland as early as thursday afternoon, and by friday morning Scotland and northern & eastern England bear the brunt.

I wouldnt quite go that far, but it has certainly been many years since we've had this sort of pattern. This weather pattern, cool/cold zonality with severe storms, was fairly common in the early 90s when I was a child. This was the very weather I came to expect in December and January. For example, although a tad less extreme, the following charts are very similar to today's output. Not to mention the January 1993 "Braer" storm, which bottomed out at 916hpa north of Scotland, and delivered a few hours of lying snow to sea level here from a returning polar maritime WSWly! The late 90s/early naughties was pure mild zonal muck in comparison. This time last year I experienced more snow in 4 weeks than I had experienced in my lifetime, so Im satisfied for now. I certainly wont be obsessively analyzing the position of the 528dam line at t+384, for many years, thats for sure. This week's weather has the potential to be both exciting and scary, bring it on!

I notice there's been a slight upgrade of the intensity of the cold pool crossing Ireland tonight, if the GFS is to be believed.. 500-1000 thicknesses at Dublin Airport are now expected to fall to 529dam during the early hours of Friday morning, where as previous runs all week had been forecasting it to bottom out around 531dam. GFS sampled points- EIDW

Im across the Irish Sea from you, in a coastal town, and all too-often experience marginal conditions during easterlies or northeasterlies. I wouldn't be too concerned, unless you live close to sea-level or right on the coast itself. As long as the winds are blowing in off the sea, temps near the coast will stay above freezing. It will still snow, but theres a greater chance of it thawing at times. Its amazing what a short distance away from the coast, and little bit of altitude will do. There could be lying snow a mile or two inland at 50m asl, while closer to the coast you will get nothing but wet snow that quickly thaws. You may find that many of the showers will fall as soft hail rather than actual snow.

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