Watching The Channel Low

[MR EXTREMES]

Just to say exellent video and a quality update, 10/10. Whens the next update, tomorrow morning would be ideal just to see if we are still on track.

Who's voice over is it, is it you Paul?

yeah i agree great video cheers for that.

[stoke weather watch]

The return back on Monday may possibly be cancelled, if not it will be very rough indeed.

Although the passenger operators on the UK-Spain routes (I think there are 3) usually put the bigger vessels out, designed to withstand the Bay of Biscay.

The ship they use is the Pride of bilbao and she is not good in bad seas!!!

[wellington boot]

The ship they use is the Pride of bilbao and she is not good in bad seas!!!

I sailed on the Pride of Bilbao a number of years ago during the summer. We just missed a big storm (by a couple of days) and had sunny skies and calm waters all the way down, but heard tales from passengers travelling their return leg of horrendous conditions coming the other way...

And to get back on topic... the sad fact (for me in Oxford and other southerners... ) is that all the models have trended towards the gfs to the extent that they're all showing pretty much the same scenario now. I can't see this low suddenly changing track and going south. With agreement this broad, one has to think there is less doubt than usual.

Of course, snow might be possible at some point, but in general I suspect this might be an underwhelming couple of days for the south. Not more than a few inches in favoured areas I'd think.

There, now let's hope my pessimism will tempt the snow to come and prove me wrong.

[Roger J Smith]

Will be posting an extensive update at about 0500 GMT. Just wondering if anyone has seen the buoy report from the Brittany buoy at about 47N 8W showing sudden increase to 62 knot winds SSW.

Suspect data error is possible since this report (03z) fails to mention air temperature in contrast to previous reports.

Satellite imagery does not show that much intensification (yet) ... and there are no other ship or buoy reports to support this.

However, this is a minor point in the evolution of the system, checking latest model runs and will report back on the ongoing developments.

[Roger J Smith]

UPDATE _ 0445z Mon 9 Feb

_____________________________

Low appears to be following the GFS evolution and on the 00z model run deepens to about 968 mbs south of the IOW by around midnight. Full moon is at 1450 GMT. This factors into the potential impacts, as lunar perigee just passed on 7th (20z) will have all high tides running 1-2 m above normal where strong winds are onshore. This will be complicated as the low approaches with strong ESE winds likely and departs with strong NNE winds likely. Would expect some overtopping of south coast seawalls and harbour installations at the mid-day high tides and possible high water on the east coast of England at the midnight to 0200 high tides. There may also be cases of unusual low tide situations around 1800-2000h where strong NW winds are blowing behind the low centre.

Getting to the weather interest, the low appears to be winding up to become intense by 1200h and especially after 1500h.

First of all, France is going to take a direct hit as with the earlier storm two weeks ago, but this time the strongest winds will be further north towards the Loire valley and across much of northern and central France inland. If this low were to stray off the predicted track through the Channel, any part of southeast England happening to lie on the south side of the track could also get into this very strong SW wind event (expecting sustained 50-70 mph winds with gusts 90-110 mph in France and potentially over some parts of the Channel towards the French side ... this would include the Channel Islands).

Too close to call from my perspective whether the low centre could veer the small amount off course to include places like Shoreham, Brighton and east Kent in this extreme wind zone, but would say the odds against it are about 2:1.

Even so, winds will be very strong from the SE ahead of the low centre, not as strong as the SW'lies to the south of the track, but strong enough, at 55 gusting to 80 mph. The further east you are along the south coast, the more likely you are to see gusts above 70 mph which should be about the starting point for Cornwall, so as the low tracks along the south coast, it will intensify during the evening and induce these even stronger winds, with the slight potential of seeing the maximum gusts expected in France.

Inland over southern England, the winds will be generally about 35-60 mph from the east, backing to NE then N during the night. Exposed higher elevations could also see gusts to about 70 mph.

Now, the all important question, rain, sleet or snow?

Yes to all three. But mainly, this will be rain for the south coast and southeast England, snow for central and some parts of northern England, and Wales, while sleet will mix in at times along the transition zone. I don't think the dynamics favour freezing rain at many locations but there could be a pocket of that as well. Snowfall amounts will depend as much on elevation as on regional considerations. Higher parts of southwest England could see the rain changing to snow as soon as the low centre has gone past to the south, and this could be topped up by sea effect from the Bristol Channel across Dartmoor for example, to 20-40 cms. Other higher areas like the western part of the Salisbury plain could see 10-20 cms. Further east in southern England, only the higher ridge tops are likely to see much snow although it could be snowing down to sea level near the end of the event giving a coating of 1-3 cms. Meanwhile, the rainfall in southern England could be as much as 50 mms in places, and there is a real risk of urban and small stream flooding when snow melt is factored in. Temperatures will briefly rise to about 8-10 C accelerating the snowmelt.

From south Wales across the Midlands, I expect the storm may begin with sleet, change to all rain at lowest and southerly locations briefly, then over to all snow, and the totals could be 10-20 cms in a near blizzard as winds howl in from the North Sea at 40-60 mph especially over higher portions. This will tend to taper off to 5-10 cms in similar conditions, with less chance of sleet and little chance of rain, in Yorkshire and the northeast, as well as central Wales and the northwest Midlands.

If the UKMO track verified and the storm was GFS-intense, then we might be looking at a more widespread snowstorm including larger parts of southern England, but I should stress, even on the GFS track and evolution, the snow currently on the ground is tilting the balance towards snow due to evaporative cooling of the lower layers. I think that snow may become heavy in many parts of inland south central England after midnight. Don't concentrate on the conditions ahead of the low, the potential for snowfall in the south lies in the second half of the event when the warm advection phase is over and not only off to the east, but also weakening in the system in general.

Amidst all of that this may not be too clear, but the south coast near sea level is likely to see a mixture of rain and melting snow near the end of the storm as temperatures start to fall back to 1-2 C. Inland at any sort of elevation it will be a completely different story with heavy accumulating snow, wind-driven and drifting badly over open areas.

[Snowcheeks]

Thanks Roger - sounds interesting - just wondering why the French meteo isnt putting out any advance weather warnings - why do you think that is?

aaaaah it changed Meteo France it was all yellow last time I looked

[mettalfabrik]

Nice one RJS

WOUK50 EGRR 090352

GALE WARNING MONDAY 09 FEBRUARY 0347GMT 22

WIGHT PORTLAND

SOUTHERLY GALE FORCE 8 EXPECTED SOON, VEERING NORTHWESTERLY SEVERE

GALE FORCE 9 LATER

SHANNON

NORTHERLY GALE FORCE 8 EXPECTED SOON

http://weather.gmdss.org/image/metarea2.jpg

WONT50 LFPW 082047

A

SECURITE ON METAREA 2, METEO-FRANCE,

WARNING NR 85, SUNDAY 8 FEBRUARY 2009 AT 2040 UTC

GENERAL SYNOPSIS, SUNDAY 8 AT 1200 UTC

LOW 1004 43N27W, MOVING RAPIDLY NORTHEAST AND DEEPENING, EXPECTED

994 46N20W BY 09/00 UTC, THEN 984 48N13W BY 09/12 UTC, THEN 979

49N03W BY 10/00 UTC.

NEW LOW EXPECTED 982 51N49W BY 19/12 UTC, MOVING NORTH EXPECTED 972

54N51W BY 10/00 UTC, WITH ASSOCIATED TROUGH REACHING WEST OF

FARADAY.

HIGH 1027 27N25W, WEAKENING GRADUALLY.

NEW HIGH EXPECTED 1026 35N38W BY 09/12 UTC, THEN 1027 39N27W BY

10/00 UTC.

FARADAY

CONTINUING TO 09/06 UTC

IN EAST: CYCLONIC 8. SEVERE GUSTS.

AGAIN FROM 09/21 UTC TO 10/06 UTC AT LEAST

IN WEST: SOUTHWEST 8. SEVERE GUSTS. HIGH SEA.

ROMEO

CONTINUING TO 10/00 UTC

CYCLONIC 8, THEN INCREASING 9 OR 10 SOON, DECREASING NORTHWEST 8 OR

9 FROM WEST LATER. SEVERE GUSTS. HIGH SEA.

ALTAIR

CONTINUING TO 09/06UTC

CYCLONIC 8 OR 9. SEVERE GUSTS. SEA BECOMING HIGH.

AGAIN FROM 10/00 UTC TO 10/06 UTC AT LEAST

IN FAR NORTHWEST: SOUTHWEST 8. SEVERE GUSTS. HIGH SEA.

CHARCOT

CONTINUING TO 09/21 UTC

SOUTHWEST 8 OR 9, INCREASING 9 OR 10 IN NORTH, AND VEERING

NORTHWEST 8 OR 9 FROM WEST. SEVERE GUSTS. HIGH SEA.

NORTH OF ACORES

CONTINUING TO 09/06 UTC

NORTHWESTERLY 8 OR 9, LOCALLY SOUTHWEST IN EAST AT FIRST. SEVERE

GUSTS. HIGH SEA.

NORTH OF JOSEPHINE

IMMINENT AND CONTINUING TO 09/15 UTC

SOUTHWEST 8. SEVERE GUSTS. HIGH SEA.

PAZENN

FROM 09/03 UTC TO 10/03 UTC AT LEAST

SOUTHWEST 8 OR 9, INCREASING 9 OR 10 SOON, TEMPORARILY 11, AND

VEERING WEST OR NORTHWEST FROM WEST. SEVERE GUSTS. SEA BECOMING

HIGH OR VERY HIGH.

FINISTERRE

FROM 09/03 UTC TO 10/03 UTC

SOUTHWEST 8 OR 9, VEERING WEST OR NORTHWEST LATER. SEVERE GUSTS.

SEA BECOMING HIGH.

CANTABRICO

FROM 09/06 UTC TO 10/06 UTC AT LEAST

SOUTHWEST INCREASING 8 FROM WEST, THEN INCREASING 9. SEVERE GUSTS.

SEA BECOMING HIGH.

IROISE, YEU, ROCHEBONNE

FROM 09/06 UTC TO 10/06 UTC AT LEAST

SOUTHWEST 8, INCREASING 9 OR 10 SOON, THEN VEERING WEST OR

NORTHWEST 10, TEMPORARILY 11. SEVERE GUSTS. SEA BECOMING HIGH OR

VERY HIGH.=

Edited February 9, 2009 by blackdown

[West is Best]

The overnight runs have the low running right along the channel, or if anything a shade further south.

I think we can expect blizzard conditions to the north of the low, and snow down to low levels in the south as it pulls away. This could be quite severe.

[mettalfabrik]

looking at the MET-O Radar latest ,that s pretty intense heading into the SW i,ll expect that very soon here

very calm here at the moment ,with a hellva lot of lying snow about

eh up just started raining but no wind as such

Edited February 9, 2009 by blackdown

[hilldweller]

Just posted this on the model discussion thread but its more applicable here.

A trend is emerging from the models especially the UKMO to track this LP further N.

Now this could change and to be honest anyone N of the M4 and away from the E coast is at risk. However I expect the BBC forecasts to change somewhat tomorrow and will move this risk of snow further N. I also expect the BBC forecasts to change for the Midlands with the precip starting as rain but turning to snow during Monday night rather than starting as snow. However in the area I highlighted it could start and remain as snow especially on higher ground.

If I had the money I would book myself into a B&B in Buxton, Derbyshire to witness an almighty blizzard!

Thanks for that TEITS

Edited February 9, 2009 by keviwal

[Roger J Smith]

Estimate the low centre to be 983 mbs near 48N 15W, the K1 buoy somewhat to the northeast of that location has continued to report NE winds ... in this early stage, rain is spreading into coastal regions as far north as Wales ... the circulation has not intensified yet, and when it does, air mass mixing will probably result in some decrease in T/dp values around South Wales, Bristol and Thames valley, once the colder air still present over the east Midlands begins to enter the circulation.

I think that despite the usual reliable model performance at 12-18h nowadays, there is a slight uncertainty left with this track and I would not want to rule out a track that crosses some part of southeast England. This is going to be a day of nowcasting for sure, the thing I should stress with this system is potential for rapid development and change, in part due to the snow cover interacting with the moisture flow.

As to France and weather warnings, they may be discounting the GFS, but I tend to rely on it in windstorm development situations, occasionally you get burned but usually it is the best performer on that stage. If the GFS verifies, France will have a high impact windstorm across the north. Channel Islands may be included in it too.

[mettalfabrik]

Wight, Portland, Plymouth

Southerly 6 to gale 8, veering northwesterly 7 to severe gale 9, perhaps storm 10 later. Moderate or rough, occasionally very rough later. Rain or squally showers. Moderate or good, occasionally poor

Biscay, FitzRoy

Southwesterly veering northwesterly gale 8 to storm 10, perhaps violent storm 11 later. Rough, becoming high or very high. Rain or squally showers. Moderate or poor

jersey met latest take on the track of the low

Summary:

Rain and drizzle clearing this evening.

STRONG WIND WARNING:

At the time of issue there was a Strong Wind Warning in force for the Channel Islands Area.

General Situation:

At 9 pm, low 995 milliabars 700 miles west of Biscay expected to move NE passing close to the Channel Islands in the early hours of Tuesday.

Forecast from 1 am Monday to 1 am Tuesday

Wind: W’ly F3 to 5, backing SE by morning and increasing F6 to 7, veering SW in the afternoon, possibly touching gale F8 for a time, becoming cyclonic variable towards midnight.

Forecast: Fair becoming cloudy with outbreaks of rain around dawn, persistent and heavy at times in the afternoon.

Visibility: Good becoming moderate to poor.

Sea State: Moderate to rather rough, becoming rough to very rough in the afternoon.

Swell: Becoming confused with total waves 6 to 10ft.

Sea Temp: 7°C

Forecast from 1 am Tuesday to 1 am Wednesday

Wind: Cyclonic variable soon becoming NW gale F8, perhaps severe gale F9 for a time, decreasing F5 to 6 later on Tuesday.

Forecast: Rain clearing to fair periods and isolated wintry showers. A further period of rain possible Tuesday night.

Visibility: Moderate to poor in rain, otherwise good.

Sea State: Rough, becoming very rough for a time, moderating later on Tuesday.

Data from Jersey Met, last updated on Monday 9th February 2009 at 05:59

centre 50N-2W by midnight

WONT50 LFPW 090543

A

SECURITE ON METAREA 2, METEO-FRANCE,

WARNING NR 87 , MONDAY 9 FEBRUARY 2009 AT 0539 UTC

GENERAL SYNOPSIS, MONDAY 9 AT 0000 UTC

LOW 994 46N19W, MOVING NORTHEAST AND DEEPENING, EXPECTED 983 48N12W

BY 09/12 UTC, THEN 973 50N02W BY 10/00 UTC. ASSOCIATED TROUGH

CROSSING BAY OF BISCAY LATER.

[TEITS]

Due to the GFS proving to be exceptional at this range I thought I would take a close look.

http://www.wetterzentrale.de/pics/Rmgfs273.gif

http://www.wetterzentrale.de/pics/Rmgfs272.gif

http://www.wetterzentrale.de/pics/Rmgfs274.gif

http://www.wetterzentrale.de/pics/Rmgfs278.gif

Main bulk of precip remains around Midlands/Wales/Lincs/Humber/S Yorks.

However what a nightmare upper temps are around -3C,DP 1C, temp 1C. Now heavy snow can fall in these conditions but towards Lincs/Humber this is more likely to fall as rain.

Just an observation but looking at the sat pics and it appears to me the centre of the LP is slightly further S than the models prog.

[Kiwi]

Just an observation but looking at the sat pics and it appears to me the centre of the LP is slightly further S than the models prog.

Latest forecast on Sky seems to have the low running much further south than I'd expected with the cut-off for any precipitation being the north midlands.

Should be an interesting day.

Edited February 9, 2009 by Kiwi

[kold weather]

Certainly not easy to forecast where it will snow, possibly alot of local variation. Already 5-10mm in the south coast before the heavier and stronger front comes in during the afternoon. Where it does snow temps may well drop far enough for it tobsettle even if the ground is a little wet beforehand.

[nick sussex]

Orange warnings out on meteo France for the Bordeaux area ne wards into Northern France, winds gusting to between 130/140kms an hour on the coast and 100/120 inland,thankfully no warning down here for the Pyrenees Atlantique which comes as a relief. I'm hoping as I'm right on the eastern fringe of this dept I may escape any drama.

In terms of snow potential for this low as Roger S says the early stages are unlikely to produce snow away from the northern flank of the low and north of the occlusion, its as it clears eastwards thats when the interest increases more generally.

http://www.wetterzentrale.de/pics/brack0.html

As the low centre passes eastwards at midnight the sw is out of the mild sector and its at this time if theres going to be back edge snow we will see reports coming in from the sw of England. Although looking at the fax chart we see the warm front clearing earlier there is still a hangback of milder air in the centre of the low however even at this stage things are subject to change so its really down to nowcasting.

Edited February 9, 2009 by nick sussex

[TEITS]

Latest forecast on Sky seems to have the low running much further south than I'd expected with the cut-off for any precipitation being the north midlands.

Should be an interesting day.

Taking a look at all the models I would agree the N extent is around N Midlands possibly getting into S yorks.

The BBC seem to be suggesting rain turning to snow rather than starting as snow. However we have already seen these past few days how the GFS can be ahead of the BBC at this range. I think the rain turning to snow is most likely but after my experiences this week I wouldn't be surprised if some parts see this start and remain as snow especially in N Wales/NW Midlands.

[nick sussex]

Taking a look at all the models I would agree the N extent is around N Midlands possibly getting into S yorks.

The BBC seem to be suggesting rain turning to snow rather than starting as snow. However we have already seen these past few days how the GFS can be ahead of the BBC at this range. I think the rain turning to snow is most likely but after my experiences this week I wouldn't be surprised if some parts see this start and remain as snow especially in N Wales/NW Midlands.

I'd agree Dave those areas you highlighted look to have the best chance for an all snow event,its funny how the ukmo have the northernmost solution since it began as the most southerly track of the low.

[Coast]

I'm expecting torrential rain (as has started already this morning) possibly turning sleety overnight. I will also be keeping an eye on the winds sweeping in later.

[Yeti]

Taking a look at all the models I would agree the N extent is around N Midlands possibly getting into S yorks.

The BBC seem to be suggesting rain turning to snow rather than starting as snow. However we have already seen these past few days how the GFS can be ahead of the BBC at this range. I think the rain turning to snow is most likely but after my experiences this week I wouldn't be surprised if some parts see this start and remain as snow especially in N Wales/NW Midlands.

Dave, every single model shows at least some precip making it into N Yorks, the UKMO and ECM especially so! Even if the GFS came off, it would be heavy for a time where I am. E Yorks more so.

[TEITS]

I'd agree Dave those areas you highlighted look to have the best chance for an all snow event,its funny how the ukmo have the northernmost solution since it began as the most southerly track of the low.

I must admit Nick since this cold spell began with the exception of the streamer the BBC/UKMO haven't really done very well at this range.

My immediate concern is flooding in my area. At the moment we still have around 6inches of lying snow and together with the rain/snow this could cause further problems. The other problem is I look at the GFS and the conditions its progging i.e DP,uppers,surface is pretty much the same as I have seen since the last snowfalls. I do wonder however what warming effect the N sea will have as the LP pulls away because despite the colder temps the influence of the N sea could see this remain as rain for my area.

Im basically planning for the worst today. Despite expecting rain im still going to get a few supplies in just incase my family, who I rely on, can't get to me tomorrow.

[snowking]

I still think even looking at the NMM this morning, the zone id expected to get the heaviest of any snow that does fall (north of the M4 up to brum) is the most likely area. Looking at the thickness values the coldest air starts to wrap itself around the low from around 1900GMT this evening, from south wales running right along the M4 corridor. The second heavier pule of precipitation then moves NW'wards to hit these areas from around 2200GMT. It could be around then we start to see the first of the snowfalls reported

As for accumulation, however, it will have to be very heavy after todays rain and snowmelt to settle.....although with the borderline nature of the event some large flakes i think can be expected

SK

[nick sussex]

I must admit Nick since this cold spell began with the exception of the streamer the BBC/UKMO haven't really done very well at this range.

My immediate concern is flooding in my area. At the moment we still have around 6inches of lying snow and together with the rain/snow this could cause further problems. The other problem is I look at the GFS and the conditions its progging i.e DP,uppers,surface is pretty much the same as I have seen since the last snowfalls. I do wonder however what warming effect the N sea will have as the LP pulls away because despite the colder temps the influence of the N sea could see this remain as rain for my area.

Im basically planning for the worst today. Despite expecting rain im still going to get a few supplies in just incase my family, who I rely on, can't get to me tomorrow.

I wouldn't rule out snow in your area as the low clears eastwards, I think its more immediate coastal regions that will have a problem with an onshore wind modifying the situation towards just rain. It will be intereresting to see which model comes out on top here, everyone knows I think the gfs has been very poor over the winter in the more medium term but seems to be not too bad with picking up some small detail at close range. Regarding the ukmo I have been a little disappointed with their general accuracy during the cold spell especially as they have a new 48hrs model called MOGREPS aswell as the existing one which is basically there to give more accurate forecasts within that time period.

Edited February 9, 2009 by nick sussex

[Terminal Moraine]

I'll be awaiting the Met' Office weather warning updates later this morning with interest. Due to time constraints the BBC Radio 4 forecast was suitably vague about the northern extent of the precipitation and seemed to indicate a 'rain turning to snow tonight situation' even as far north as the north Midlands, they then went on to mention the likelihood of snow as far north as northern England tonight but with maximum amounts of around 10cm.

If GFS is correct I'd be expecting more of a complete snow event here with perhaps 10-15cm, accompanied by a strong NE wind, later tonight.

A very difficult forecasting situation for the Met' Office.

[TEITS]

Dave, every single model shows at least some precip making it into N Yorks, the UKMO and ECM especially so! Even if the GFS came off, it would be heavy for a time where I am. E Yorks more so.

The trouble is the UKMO seems to track this further N than any other model and the ECM is designed as a medium range model. The areas I highlighted are the zones that show the heaviest precip which could be factor tonight due to evaporative cooling.

The models have always suggested the zone between Wales/Midlands being at greatest risk and this continues. After the performance of the GFS at this range im going to stick with this and the NMM.

NMM precip at midnight.

Even the BBC are suggesting these locations despite the UKMO having the track further N. Now im not saying you won't see snow but the area im focussing on is those in the main risk zone. Whenever a LP tracks along the channel these locations will always be in the main risk zone and always have been.

I'll be awaiting the Met' Office weather warning updates later this morning with interest. Due to time constraints the BBC Radio 4 forecast was suitably vague about the northern extent of the precipitation and seemed to indicate a 'rain turning to snow tonight situation' even as far north as the north Midlands, they then went on to mention the likelihood of snow as far north as northern England tonight but with maximum amounts of around 10cm.

If GFS is correct I'd be expecting more of a complete snow event here with perhaps 10-15cm, accompanied by a strong NE wind, later tonight.

A very difficult forecasting situation for the Met' Office.

Your in prime position IMO.

Do you have a spare room. :lol: