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The huge low pressure system in the Atlantic, with very cold uppers, is giving rise to a lovely convective 'rash' on satellite presentation.

Sorry but its not pointless, if you had read what I said about the charts I posted tie in with the hints from the pros at Exeter regarding mid / late March..all to play for!

We are entering the time of year when we can see quite a difference in conditions across the UK as the Polar and Tropical air masses battle for supremacy.The coming few days are quite interesting from this pov especially with an active Atlantic jet tracking around our latitude. A few images from the GFS 06 z for this coming Wednesday for example There's the jet running across the south,the 850hPa temperatures and the surface temperatures modeled at that time clearly illustrating the differences between north and south. We can see dramatic changes between locations at this time of year from say blizzards in upland Scotland to double figures and bright periods in the far south depending on where the dividing line(the jet)is.These differences further emphasised by heights above sea level in any polar incursions. I think the following week or two could well turn up more of these sort of scenarios with the current Northern Hemisphere pattern being shown.

For the next ten days the GFS remains unsettled with temps around average. perhaps a tad above, with a strong jet continuing to pour forth from the southern states , This morning Ewan forms west of Ireland and quickly runs NE and deepens to be 977mb over Wick by 1800z. So briefly some strong SW/W winds in the north west and some snow. This quickly slips away to the NE as the amplification out west gets underway as the Azores ridges and the deep low between Iceland and Greenland tracks south east over Britain as it fills establishing a large complex area of low pressure over the UK and points east, including another intense little low that has spawned in the circulation bringing some more wind and rain. This low quickly moves away SE followed by some very brief ridging before the next complex low pressure area arrives bringing periods of rain next weekend. Albeit it's relatively warm rain. There is some brief ridging as this area also fills and moves away before the next system arrives at the beginning of next week. It will certainly be a "get in there" from Sidney when he sees the latest GEFS

Although there is indications of the pattern change with tonight's anomalies there is no agreement on the nature and timing of this, In the 6-10 period they are all on the same page with the intense vortex N. canada, Siberian ridge and the the high cell over Greenland with the negatively tilted trough into the Atlantic. This still leaves a strong westerly and jet leaving the states but with the gradient weakening in the eastern Atlantic and perhaps some influence of the high cell to the north of the UK there would appear to be an indication for things to become a little quieter for the UK This becomes a little more complex as the aforementioned changes are underway during this period and by T240 the vortex has become more diffuse over the Pole introducing some very cold air, particularly in Alaska accompanied by the Atlantic trough becoming more neutrally orientated and thus some ridging in the vicinity of the UK. I think we can safely say a pattern change is looking like a probability but as to where it will end up is still in doubt. Temps still around average, perhaps a tad higher but tending to some N/S bias

Some snowfall surprises for a few I suspect from tomorrow afternoon through to Tuesday morning, especially those located further west across the UK where most of the precipitation will be being exposed to the Atlantic. Sub 528 dam engulfs the UK & Ireland Dew points at or below freezing With low heights, the cold atmosphere and ever increasing sun strength there will be some big wintry showers tomorrow late afternoon with rain, sleet, hail stones, increasing snowfall and thunder as convection peaks inland. Could be some decent coverings in the west overnight even to low levels!

Scope for some wintry showers pushing S/E Monday night, As temps drop into the evening under a chilly N/W wind. As shown by the in-house NetWx-SR Model.

Yes tomorrow looks an exciting day weatherwise with some big wintry showers and surprise accumulations, beautiful cloud formations..beats the boring MLB dry, dull dross we had for most of the winter!..enjoy!

I think that there might be a few surprises for a lucky few on Monday night and into Tuesday, could have some settling snow particularly on higher ground. Always remember the Birmingham snow in -3c uppers and the late October snowfall in the home counties only a few years ago. I love surprise snowfall its the best.

Nice spell of spring-like anticyclonic weather in the extended range on the Gfs 12z..very pleasant in the sunshine.

Casting the net out further into March, there are some wintry signs from the GEFS 6z which would tie in with the met office hints at cold outbreaks with snow in places during mid / late March which to me is exciting considering how insipid the last three months have been..this isn't the time for coldies to throw in the towel with charts like these!

The Gfs 6z shows some wintry ppn during the coming days / night's, especially further north and with elevation although later tomorrow there is even a risk of snow in Ireland, Wales and the southwest.

First proper Greenland High maybe for a long long time???

County Kerry today

Might be interesting, but probably not, but the gfs is trying to interrupt the Atlantic influence by introducing the idea of more permanent ridging in the vicinity of the UK as a result of some renewed amplification

Was in Reykjavik this morning they had 51cm of snow over night...... unbelievable sight

The Gfs 6z turns more spring-like temperature wise during low res as winds become more southerly in direction pumping milder air up from southern europe / azores.

Certainly looks like a classic 'kitchen sink' situation both Monday and Tuesday with some heavy showers around bringing snow quite widely over higher ground even in the south.

The problem with a southerly tracking jet when Greenland heights are not strong is that it just leaves much of the UK under the influence of successive Atlantic lows,thus a wet and windy regime with frequent frontal systems traversing the country. Really only the Scottish highlands are likely to see meaningful snowfall in the chilly air up there. The real cold is locked to our north down to about 60N where the -6/8C uppers lurk No sign of northern blocking strengthening sufficiently to bring a taste of Winter any further south so we are looking at a mobile westerly unsettled spell going into early March. My least favourite set up,wet and chilly at times but nothing out of the ordinary temperature wise.I think after a week or possibly two of this i will be willing the return of some mid-latitude blocking around the UK.

Thought I'd start a new thread as other one was rather long and started back in September. Monday looking rather lively across many areas convective-wise, as a cold vortex originating from southern Greenland drops SE over UK and creates rather steep lapse rates atop of moist maritime flow which will be weakly heated in the increasingly strong sunshine as we head into early Spring. Enough CAPE and wind shear forecast for me to warrant a marginal risk of severe weather toward SE England and E Anglia - primarily for isolated strong/damaging convective gusts in heavier showers/storms, but a brief isolated tornado can't be ruled out with veering winds and increasing strength with height. Storm & Convective Forecast Issued 2017-02-26 23:12:52 Valid: 27/02/2017 00z to 28/02/2017 00z CONVECTIVE / STORM FORECAST - 27TH FEB 2017 Synopsis Upper low/cold vortex, that broke away from Polar Vortex over Greenland over the weekend, moves SE across the U.K. During Monday, steepening lapse rates and creating an unstable airmass across the U.K. A surface low, just NW of EIRE at noon Monday, will drift east across S Scotland in the afternoon / evening, a cold front will clear E Anglia and SE England early afternoon followed by troughs moving through in the increasingly cold but unstable SWly veering Wly flow. ... EIRE, N. IRELAND, ENGLAND, WALES, W SCOTLAND... Increasingly cold air spreading east aloft (500mb temps <-35C across western U.K.) will create steep 850-500mb lapse rates (31-32C fall with height) atop of moist maritime airmass which will be weakly surface heated in sunny spells. As a result, models simulate 200-400 j/kg CAPE by early afternoon / peak warmth, this will support heavy showers and scattered thunderstorms which, given low heights / freezing levels, will produce hail, sleet and snow over hills (and lower elevations in heaviest cells) and also strong convective gusts. A low risk of localised severe weather does exist on Monday in association with more organised areas/band of storms that develop along cold front moving east across England and Wales during the morning and also one or two troughs following into the afternoon, particularly across the southern end where stronger winds aloft near jet and veering with height may allow forced convective updrafts along to organise. More organised bands of convection/storms would be capable of drawing strong winds aloft down toward the surface as isolated damaging gusts - perhaps 50-60mph inland and 60-70 with exposure in heaviest showers/storms. Also, winds veering and increasing with height may allow updrafts to rotate into a few funnel clouds or even isolated brief tornado/waterspouts. Therefore have issued a MARGINAL risk for southern counties + E Anglia where overlap of CAPE, wind shear / stronger winds aloft are enhanced. Issued by: Nick Finnis

As others have started some possible snow showers over high ground tomorrow even in the south and wintry showers widely at lower levels, some accumulations may be possible. Snowy surprises maybe????

Update for the week to February 25th The current 5 day trailing average is on 14,360,000km2 while the 1 day extent is at 14,362,000km2. (All the following data is based on a trailing 5 day average) The daily anomaly (compared to 81-10) is at -1,102,000km2, an increase from -1,091,000km2 last week. The anomaly compared to the 07, 11 and 12 average is at -293,000km2, a decrease from -330,000km2 last week. We're currently 3rd lowest on record, down from 2nd lowest last week. The average daily change over the last 7 days was +17.4k/day, compared to the long term average of +19.0k/day, and the 07, 11 and 12 average of +12.1k/day. The average long term change over the next week is +5.9k/day, with the 07, 11, and 12 average being +19.0k/day. The extent increase so far this February is the 12th largest on record. To achieve the largest increase, a gain of at least 58.8k/day is required (at least +146.4k/day with with single day values), while the smallest increase requires a loss of at least 191.4k/day (loss of at least 478.9k/day with single day values) and an average increase requires a loss of 31.1k/day (loss of 78.8k/day with single day values)

Yes story of this winter, always out at D10, sometimes D8 or D9, and then gone! Look at all that cold just to our east though at D10. You never know though we might get lucky this time, it was ECM that spoilt the last party if I remember correctly in early February, maybe this new one will be the real deal!

Sums it up Frosty! my favourite chart on ECM is always at 240, no exception here

Interesting Ecm 12z with a colder first half to the week with wintry showers and night frosts, then the cold air retreats north as complex slow moving trough (s) move across the uk and temps recover for a time but then once it's finally cleared away to the E / NE the cold air (still in situ across the far north) spreads south again as a ridge extends southwards from iceland and at the same time, the azores high ridges NE and they merge at T+240 which looks chilly and increasingly anticyclonic with pleasant sunshine and frosty nights..plenty going on..an unsettled spell but ends on a high note. :- )

There's a surprise, 2000+, 'winter' month above average, well I never

I was looking more at the intensity but you're correct - North Wales could receive an short heavy period of snow as it passes through the afternoon.

The Gfs 12z shows snow around later tomorrow, especially nw england, wales, ireland..even southwest england! Overnight it turns frosty with icy patches.

Certainly windy across west Wales, southeast Ireland, Irish Sea currently with widespread gusts of 50 - 70 mph. Wind. Recent gust of 75 mph Capel Curig.

The GEFS 6z mean shows a generally unsettled outlook for the next few weeks although just for a time, high pressure tries to ridge up from the south but on balance, doesn't succeed..it looks like typical early spring weather with the lowest temps in scotland and closer to average further south..hints of a possible cold snap later with mid atlantic ridge and scandi trough.

Yet another winter with a positive NAO. The Finnish guys with the research are proving right. Declining solar activity -> Positive NAO. http://onlinelibrary.wiley.com/doi/10.1002/2013JD021343/abstract So, this is the final winter with this correlation for a while.

Oh THAT F word. Lol

Wheres all the Snow? Looked at the Braemar snowgate web cam, No Snow. We have had some very mild sunshine down south with all the daffs out and the grass growing already, another early Spring. Coming up to Scotland in April, love your part of the world, you are very lucky to live in such a nice unspoilt part of the world. Good Health to you all.

12C Last sub 2C March in 1883. Last sub 3C, last sub 4C, last sub 5C and last sub 5.5C March in 2013.

I also think it's a great idea, particularly when we get a conveyor belt of storms, even if it's just to say to your neighbours we best repair the fence Doris mashed up! Though Ewan isn't supposed to impact on us in CS England, the fact he's on his way has spurred me to get outside and dispose of some of the debris from Thursday before it goes on another journey!

The Met Office never did name Doris early in Feb, that was certain newspapers jumping the gun, in their own usual hype to sell copy. http://www.netweather.tv/index.cgi?action=news;storyid=7978;sess= . They were very quiet this week when real Doris appeared. The level of severe weather warning Yellow/amber or red, and so naming of storms relates to the impacts of the wind not just the strength of wind/amount of rain or snow. I think the name storm process with Doris worked amazingly well, it was an ideal event for it. The next name is Ewan with an 'a', the list was made last autumn. The Met office is using Ewan, the list and how the naming process works is here http://www.netweather.tv/index.cgi?action=news;storyid=7682;sess= A storm will only be named when an amber alert is issued (orange in Eire).

Indeed it isn't that unusual. April 1989, late March and early April 2008 gave snow to a fair few places and there are plenty of other examples, too.

Gales look to hit southern Ireland, Irish Sea, clip NW Wales. Just windy later as low heads up over Scotland and away, maybe affecting far north of England too. Lot of uncertainty about development of this low. Not a repeat of Doris for Midlands or eastern England.

Well after your February prediction for a washout/wettest ever/widespread flooding, we have no reason to doubt you'll be correct.

It's been a long time since we last had a jet stream shifted south yet remaining quite strong and sending lows across the UK. With a few tweaks and occurring in the depths of winter it can be a snow-lover's nirvana - but on this occasion, due to the time of year plus quite possibly the overall warmer state of the climate, this will only ring true for up on the mountains in the north, and even there perhaps only intermittently. We have a fairly strong bit of MJO activity in the IO at the moment, in terms of wind signals - convection is lacking. The odd run here and there has toyed with moving the ridge from our N to our NE seemingly by way of response, but it seems to me that with signs of the GWO nosing into phase 4, the models are finding too much of a subtropical ridge + flat westerly signal to let this really take shape. Whether that 'too much' is down to model judgement remains to be seen - I've often seen an MJO signal rise up to seize the day having initially been underestimated... but that was back before the winter of 2016-17 which if anything has displayed the reverse tendency, catching a fair few forecasters/climatologists out - including me of course; the MJO enthusiast. Still - I believe the blocking high to our N should start to be able to exert a more direct influence in the 8-16 day range, though from what location exactly is hard to say. If the models keep trending toward MJO phase 3 to follow phase 2 then a failure of the blocking to move to our E/NE could mean that it sticks around to our N for a long time. Increasingly I worry that with GWO orbiting negative - albeit weakly - the jet might keep on firing across under such blocking to bring about an exceptionally unsettled and wet March. We could really do with the hints of El Nino in the Pacific forcing a bit of a kick in GLAAM to hold up the Atlantic lows. Hopefully a Kelvin wave will turn up to help things along.

4.8 ta

Jma to the rescue? I guess there's a first time for everything.

5.3 here please.

The JMA says no to spring and has the Jet running across the far south with Greenland heights establishing

Cloudy and breezy day here in Haverhill Suffolk. Not quite as mild as the west Country so feeling distinctly chilly in the gusty winds. An unsettled week ahead for East Anglia with a strong 200+ mph jet stream overhead. I do expect another potential wind storm next week, so will be watching the models with interest. Everything but the kitchen sink possible for the next 7 days with sunshine, heavy showers, thunder, hail and gales at times. No early signs of Spring this year.

The above post from Nick is well supported by the 500 mb anomaly charts I inferred yesterday. They have not been consistent which is why I have hesitated to post them about a week ago. Latterly though they are coming to a more reasonable concensus to the ridging developing in the upper air pattern to the north west of the UK. See the links below for how they show this in the past 24 hours. NOAA 6-10 link and the 8-14 is very similar, hence my comment 24 hours ago that it may be a spell of colder weather say 5-10 days or so. http://www.cpc.noaa.gov/products/predictions/610day/500mb.php and the ECMWF-GFS output this morning now supporting this view, with regard to the ridging positioning.. http://www.cpc.noaa.gov/products/predictions/610day/500mb.php On both sets of charts the actual height of the contour immediately south of the UK looks to be about 552 DM so not desperately cold for early March at height and with a very long sea track. Remember though these are 'average' charts and individual charts over a 24-35 even 58 hours could well be from a more NW area and thus colder. One thing it does not look like being a 'warm' 2 weeks which is what some of us would prefer!

I too worry about the halocline over our side of the basin? The open water is obviously now just normal ocean with no halocline present at all but how far did the wave/swell pass under the ice front? We saw the ice retreat to past 85N in December so we must expect that there was some mixing in toward the pole? And is the extension of the N.A.D/gulf stream only able to occur now the halocline is gone? Bering appears to save the Beaufort side from similar mixing but if the ice is all gone by late June then weather over there will still mix out the fresh water lens over the gyre. We have now seen the majority of winter and it has been record warm throughout. What will we see over the first third of melt season?

Parts of a post I made last Monday looking ahead into early March and although model guidance is still fumbling around with the surface synoptics in the medium range they are generally converging on the upper/500mb pattern with the +ve height anomaly over Greenland and Iceland with troughing underneath as I highlighted from the EPS/GEFS mean 6 days ago. The lag effects of MJO P8/1 and the stratosphere warming / PV displacement IMO likely the precursor to the +ve heights around Greenland and Iceland. Although I have lost the appetite now to hunt for snow and cold + the operationals aren't overly keen on lowering heights / developing troughing further east across central/eastern Europe, which keeps low pressure to the SW and a milder S to SWly flow at times, there is scope for pushing low pressure systems further east into Europe to our south in the medium range, 00z EC high res attempts too days 7-8 before trough disruption stops it. 00z EC high res, at day 10 keen to extend Azores ridge NE toward UK, however the EPS z500 mean and the EPS mean and spread suggest perhaps emphasis towards lower heights to the SW than the high res In the shorter-term, upper low dropping SE across UK and EIRE Monday / Tuesday brings quite low heights across the UK. Fax chart for 12z Monday shows the 528 dam line moving into the west, steep lapse rates with the low heights/cold air aloft, so will be some heavy showers with hail, thunder and even some sleet and snow in the heavier burst across the north and west - as dew point lower from the west in the chilly Pm westerly flow 00z ECM on weatherbell indicating snow for western hills on Monday (Wales, NW England, western Scotland), then perhaps a more organised area of snow moving SE across southern Scotland and far N + NE England Tuesday morning which could be tied in with a trough / front moving S /SE as winds turn more Nly for a time So don't be surprised to see some snow flakes early next week across the north and west, though settling snow moslty confined to hills daytime, though some spots in the north may see brief settling to lower elevations Monday night.

The snowiest winters of the 1990s were generally 1990/91 and 1995/96. 1993/94 was quite a snowy winter in some regions, especially the north-east, despite not being particularly cold, while 1996/97 started off with some snow events in November and December but ended very mild. The other winters of the 1990s were, however, predominantly mild. Some winters had their moments (Bristol may well have been hit by the early March 1995 snow event for instance) but they were pretty rare.