This Week's Storms - FORECAST, MODEL DISCUSSION ONLY

irish1967

Maybe it's time to start a thread for Thursdays potential storm before the 2 storms start to get muddled up on this thread

maquiladora

leahyl wrote: »

Lads from reading the last few posts it seems that both storms are shifting further north - are the winds likely to not be as severe in the south?

Thats right, but these almost always trend further north/left so it is to be expected.
Track not nailed for either storm yet though.

leahyl

maquiladora wrote: »

leahyl wrote: »

Lads from reading the last few posts it seems that both storms are shifting further north - are the winds likely to not be as severe in the south?

Thats right, but these almost always trend further north/left so it is to be expected.
Track not nailed for either storm yet though.

Ok - well I hope we get something memorable down here anyway! It could become known as the big wind of 2011 :-D

maquiladora

No big change on the 06Z GFS for Tuesday. Strong winds look confined to the north and northwest on that run.

JanuarySnowstor

maquiladora wrote: »

No big change on the 06Z GFS for Tuesday. Strong winds look confined to the north and northwest on that run.

No, storms for the North and West, strong winds elsewhere is what I see.

As for Thurs night.....

whiteandlight

For once I'm desperately praying for lots of downgrades for the system later in the week! Im getting married in mayo and a large group of people are travelling. Tuesdays one can do its worst so long as it leaves my church and hotel alone lol

WolfeIRE

Monday/Tuesday's storm doesn't look as potent as last night but Fridays storm has intensified further and is centred just north of the midlands . potentially a very dangerous and destructive storm

leahyl

WolfeIRE wrote: »

Monday/Tuesday's storm doesn't look as potent as last night but Fridays storm has intensified further and is centred just north of the midlands . potentially a very dangerous and destructive storm

We were saying the same thing about Tuesdays storm a few days ago though so that will prob move further north as well

Su Campu

As I said in the original post, strong bombing cyclones have a tendency to veer left (north) of the models' projected paths. It's called the Rosenbloom Rule.

The strong blast of freezing Arctic air from Baffin Bay is what is building the very strong jet streak which will feed this cyclone. The exact upper dynamics can be hard to get bang on so hence the wide variation in forecast intensity as well as track.

maquiladora

I know this thread is for Tuesday, but just had to share the 06Z output for that second system.







:eek:

(In before the downgrades )

leahyl

maquiladora wrote: »

I know this thread is for Tuesday, but just had to share the 06Z output for that second system.







:eek:

(In before the downgrades )

Sweet mother of divine jesus!!! :-O

munsterlegend

leahyl wrote: »

Sweet mother of divine jesus!!! :-O

would want a strong umbrella that day...

munsterlegend

WolfeIRE wrote: »

Monday/Tuesday's storm doesn't look as potent as last night but Fridays storm has intensified further and is centred just north of the midlands . potentially a very dangerous and destructive storm

But likely to veer further left and north like Monday/Tuesday modelled path now?

Sponge Bob

GFS setting up two further storms for 23rd and 25th december...they should be showing 940- core pressures by monday next as is traditional.

maquiladora

The updated yellow alert from the UKMO just posted a few minutes ago suggests that the forecasters there are not expecting Tuesday's storm to go any further north (at the moment anyway).

Monday:


Tuesday:


North of England/Scotland not included in the alert area. Though they do say :

At this stage there is some uncertainty and the public are advised to monitor forecasts to keep up to date with this warning.

munsterlegend

maquiladora wrote: »

The updated yellow alert from the UKMO just posted a few minutes ago suggests that the forecasters there are not expecting Tuesday's storm to go any further north (at the moment anyway).



North of England/Scotland not included in the alert area. Though they do say :

interesting! are models programmed to include the effect referred to by Su Campu?

only one

Sky news are showing snow in the south east and south west on Wednesday after the wind event

sunbabe08

only one wrote: »

Sky news are showing snow in the south east and south west on Wednesday after the wind event

south east of ireland or england?

only one

sunbabe08 wrote: »

only one wrote: »

Sky news are showing snow in the south east and south west on Wednesday after the wind event

south east of ireland or england?

Ireland. It was on their long rage forecast on ye red button on sky

Deep Easterly

What the guys at Exeter are thinking at this stage for Tuesday noon:



Gusty and more in line with its own UKMO run as well as GFS. Interesting that the ECMWF have it further north with slacker gradient over Ireland on both the op and en mean. Once off or start of a trend? .

maquiladora

Deep Easterly wrote: »

What the guys at Exeter are thinking at this stage for Tuesday noon:



Gusty and more in line with its own UKMO run as well as GFS. Interesting that the ECMWF have it further north with slacker gradient over Ireland on both the op and en mean. Once off or start of a trend? .

ECM has been showing that now for the last two runs.

Who will bow to who? :pac:

12Z's will be interesting...

Deep Easterly

maquiladora wrote: »

Who will bow to who? :pac:

12Z's will be interesting...

The actual 84hr fax shows something slightly different for the same time period: (Tuesday noon)



a bit more in tune with the ECMWF projection with the low centre being more 'complex' in structure but still packing a punch wind wise over Ireland.

Yep, all eyes on the 12z. Swings and roundabouts!

maquiladora

Deep Easterly wrote: »

The actual 84hr fax shows something slightly different for the same time period: (Tuesday noon)



a bit more in tune with the ECMWF projection with the low centre being more 'complex' in structure but still packing a punch wind wise over Ireland.

Yep, all eyes on the 12z. Swings and roundabouts!

955mb low right on the NI coast. That probably explains the UKMO warning for the highest winds to be in the southern UK then.

Ahorseofaman

maquiladora wrote: »

955mb low right on the NI coast. That probably explains the UKMO warning for the highest winds to be in the southern UK then.

and therefore southern Ireland as well?

ninebeanrows

Just before the 12z,

The 6z did look quite blowy for much of Ireland on Tuesday

Widespread gusts from 60-70 knots

irish1967

Lol. I love the use of that phrase.... "quite blowy" that's my kind of technical phrase

M.T. Cranium

This thread could probably use an upgraded title to reflect the severity of two storms. It's starting to look like a five-day siege of stormy weather with two peaks of intensity, as there may not be any great let up in wind speeds between Tuesday and Thursday night. Also this inter-storm period could be producing its own brand of disruptive wintry showers.

I think the UK Met warnings are influenced by the upper pattern being so cold that only a southward shift could be logically expected, and they are buying fully into the idea of a southern energy centre which will tend to reduce wind speeds for Scotland as the double-centered low approaches (but it will still be very windy there, just below warning criteria in that scenario). Personally I would put the whole of the UK under the same level of alert at this point and extend the same alert to Ireland. This thing looks intense and I don't think there will be much variation north to south for Ireland. In any case a fairly significant part of the storm comes in the warmer period late Monday so that alone would justify an alert, regardless of how strong the colder westerly portion proves to be.

I'm only starting my day so going back to get a better handle on how this is evolving off eastern Canada now. If there's a continuation of model trends on the 12z then I think our task here switches from speculation to outright warning as we might expect the other sources to be a little more hesitant -- people need to know this is coming especially given that it's a weekend and Monday looks very unpleasant to be outside trying to deal with preparation issues in a driving rain.

For a new thread title, I would suggest something like

Severe windstorms, wintry showers from late Monday 12th to Friday 16th

or anything that alerts to a long-duration, severe set of events.

ninebeanrows

M.T. Cranium wrote: »

This thread could probably use an upgraded title to reflect the severity of two storms. It's starting to look like a five-day siege of stormy weather with two peaks of intensity, as there may not be any great let up in wind speeds between Tuesday and Thursday night. Also this inter-storm period could be producing its own brand of disruptive wintry showers.

I think the UK Met warnings are influenced by the upper pattern being so cold that only a southward shift could be logically expected, and they are buying fully into the idea of a southern energy centre which will tend to reduce wind speeds for Scotland as the double-centered low approaches (but it will still be very windy there, just below warning criteria in that scenario). Personally I would put the whole of the UK under the same level of alert at this point and extend the same alert to Ireland. This thing looks intense and I don't think there will be much variation north to south for Ireland. In any case a fairly significant part of the storm comes in the warmer period late Monday so that alone would justify an alert, regardless of how strong the colder westerly portion proves to be.

I'm only starting my day so going back to get a better handle on how this is evolving off eastern Canada now. If there's a continuation of model trends on the 12z then I think our task here switches from speculation to outright warning as we might expect the other sources to be a little more hesitant -- people need to know this is coming especially given that it's a weekend and Monday looks very unpleasant to be outside trying to deal with preparation issues in a driving rain.

For a new thread title, I would suggest something like

Severe windstorms, wintry showers from late Monday 12th to Friday 16th

or anything that alerts to a long-duration, severe set of events.

Thanks MT, you are free to set up any threads you wish!

I will set up a thread maybe this evening after the outputs.

Thanks as usual for your excellent analysis.

ninebeanrows

12z GFS perhaps looking for ECM esque with the low set up, but i have no grasp over how this thing makes its moves.

pauldry

Thread title : Severe Windstorm turning out not to be as bad as anticipated as it goes too far south and sends the shallow part of the low over us and then fills a bit more as it passes us and the winds just are blowy and then the second storm goes too far north of us and we are left with just a couple of windy days and the wintry showers are hailstones.

Or is that too long for a thread title