Atlantic Lows - general discussion

[The PIT]

Although this feature seems to have been mostly downgraded from the pressure charts the forecast is still for a windy period for NI and Western Scotland 60 to 70 gusts possible later today.

[Zenarcher]

The 06z GFS run shows some very windy weather for next Thursday and Friday,

[Zenarcher]

Still looking bad for Monday. I would the North West of Scotland will see very windy weather but Orkney and Shetland will see the worse of it.

Looking ahead to the next day Wednesday looking bad again,

[Zenarcher]

12z run was an upgrade in wind speeds for tomorrow however the worst of it looks to be in the sea but Orkney and Shetland will get some of it,

As for Wednesday no real big changes in terms of wind speeds just a position change and it's still a similar path to Mondays storm,

Shipping forecasts have warnings out for a violent storm 11 in the far North West.

18z run will be out soon.

[Zenarcher]

Very windy morning in Western Scotland gusting to 51mph here and up to 58mph in Stornoway. Also Orkney and Shetland are expected the worst of it this afternoon into the evening with Shetland getting the worse. If Stornoway is hitting 58mph already I expect Shetland will surely get much higher later.

As for the Wednesday and Thursday storm it looks like it's been downgraded but pushed further South giving the entire UK windy weather.

[Zenarcher]

Wind has picked up here to 61mph gusts and Stornoway 64mph gusts.

Edited October 3, 2011 by weathermaster

[ZONE 51]

Could someone make a thread up on the Ex-Hurricane for mid week, should spark some interest! not an exact track yet, but somewhere is in for a rough ride..

Edited October 4, 2011 by ElectricSnowStorm

[The PIT]

Looking like a windy spell coming up for North Western and Western Scotland Southern Scotland, North and North east England during Thursday with Gusts up to 60 perhaps a little more making it tricky for high sided vehicles. As ever weakened structures and trees may have a slight problem. The track may alter slightly in the next 24 hours so worth keeping an eye open.

[Liam J]

A very windy period Thursday afternoon and evening which could cause problems for the rush hour, GFS 6z upgraded the wind speeds further. I'm not sure about the thinking behind the METO yellow warning when quite clearly areas further north from the rather limited yellow shading will be impacted from the winds - I think the whole area is to far south and about 80% of the impact area is over the sea!

Gale to severe gale force westerly winds veering NW'ly as indicated by the models impact my neck of the woods quite significantly when they occur. I'm sure parts of Western and Southern Scotland will also be feelin the brunt of the winds.

GFS predicted wind speeds Thursday afternoon on the chart below which can be massively under estimated in some locations due to other factors like funnelling winds and bouncing over the pennines etc - for that reson I have included NE England in the area that could expect to face some disruption tomorrow afternoon.

Edited October 5, 2011 by Liam J

[The PIT]

GFS 12 oz has moved it further south into South west Scotland Northern Ireland and North Wales and North West England. Winds down a wee bit as well which is good news if you don't winds. Still should be fairly lively though.

[Liam J]

GFS 18Z has a slight upgrade in wind speeds for Thursday afternoon, I expect local reports of disruption will occur tomorrow with the risk of minor damage to trees and buildings.

Northern Ireland will feel the force of the gales first before these transfer eastwards towards Southern Scotland then NW England around mid - late afternoon. Be aware of the risk for falling branches and debris at the least.

[Zenarcher]

Here's a map I made for Thursday,

[Cookie]

hasn't been to bad here today, further south has been worse affected especially on the south west coast of Scotland!

[The PIT]

Just outside the reliable time frame T111 to T123 the gfs 06oz develops a wave into quite a brief wind storm for Northern England North Midlands and North Wales. Gusts just under 70 mph predicted on Tuesday 18th.

[wimblettben]

If it verify's TP then that would probably mean at least 30 to 40mph winds down here for the southwest!

Not damaging I know, but still fun to watch.

[The PIT]

If it verify's TP then that would probably mean at least 30 to 40mph winds down here for the southwest!

Not damaging I know, but still fun to watch.

That's the problem these have the tendency disappear fairly quickly. I wouldn't be surprised if the 12 oz removed it altogether.

[The PIT]

Yup gone on the 12 oz

[Liam J]

Very strong winds shown on the 12z for North wales and NW England Monday afternoon, perhaps gust exceeding 70mph in exposed areas with mean speeds approaching 50 knots.

[The PIT]

Yes it's return again. Still a lot of chopping and changing even this close in as these little critters are difficult to predict.

[Liam J]

I think this feature may still yet have the odd trick up it's sleeve with further analysis from the models over the coming hours needed to nail on the final result.

The shortwave which is rapidly developing approaches SW Ireland around 6am Monday morning with a pressure of around 1004mb, current guidance shows it deepening 20mb to become 984mb within 15 hours and dropping 28mb in under 24 hours. This is called bombogenesis the term used to describe a depression under going very rapid cyclogenesis.

The interaction with a jet streak of some 150knts+ along with an area of high vorticity to the west of Ireland creating perfect synoptics to aid rapid intensification of this storm feature, also the 850 temps will drop some 6 degrees during the passage from +3c to -3c this could fuel T-storms on a line of convection along the cold front along with extremely strong gusts of wind.

What we can be certain of is a period of severe weather will affect Northern England, Southern Scotland and part of Wales during Monday as this feature starts to impact the UK. Curently no warnings have been issued highlighting the potential wind speeds directly, perhaps the forecasters are holding back until later this afternoon or evening as their is still a degree of uncertainty as to how severe this will be.

Currently wind gusts could reach 70-75mph with very isolated 80mph a small risk, mean speeds over exposed and coastal areas of Northern parts of NW England could be around 50mph+ and 35-40mph further inland quite a distance with gusts 60mph, Expect damage and some disruption to transport.

Bearing in mind that it wouldn't take much to push this low into being a major wind event, so any upgarde on future runs could be cause for concern for areas to be affected and. I think the chances of this being downgraded are pretty slim given the current set up and model guidance.

These features can be notoriously difficult to predict even within 24 hours, all the ingredients are there for a very intense depression to form.

Edited October 16, 2011 by Liam J

[Aaron]

I'm hoping the Pennine Lee wave winds come into play here like they usually do, otherwise nothing of interest to me.

[wimblettben]

If non of the forecasts such as Met Office or BBC bring out a warning for the areas that are going to be worst effected by this feature for tommorow then I will be utterly shocked at how bad there warning systems are currently!

[Liam J]

If non of the forecasts such as Met Office or BBC bring out a warning for the areas that are going to be worst effected by this feature for tommorow then I will be utterly shocked at how bad there warning systems are currently!

I do find the new Meto warnings quite poor, the previous warning system had a good explanation and detailed look at the expected severe weather and areas to be impacted. very sparse now and not very clear imo.

[syed2878]

Bbc has a yello worning for rain and strong wind. Nw england scotland and island.

[Liam J]

Meto shipping forecast for the Irish Sea tomorrow, rough.

Wind Southwest 5 to 7, increasing gale 8 or severe gale 9 later, perhaps storm 10 later.

Sea State Moderate or rough, becoming very rough.

Weather Rain or squally showers.

Visibility Good, occasionally poor

Edited October 16, 2011 by Liam J