Extratropical Storm Ophelia - Technical Analysis Only - MOD NOTE post #1

savj2

JJJJNR wrote: »

Could this bring about a cold snap once it heads north ?

I think it's going to north then east. Models showing a ridge just after the storm passes then back to westerlies.

Pangea

Will Ophellia be renamed according to the Met Eireann naming system?

M.T. Cranium

This concept of extratropical transition was not as developed in the 1960s or 1970s as it is now so that both Faith and Debbie (1961) were probably classified as hurricanes longer then compared to what would happen today.

Also the transition is not some instant development, no doubt if these models verify there will be remnants of the old tropical organization visible on satellite and radar but the wind field will definitely start to expand rapidly after 45N and fronts will rapidly develop, the GEM model for example has an upper low of 536 dm capturing Ophelia and that's going to result in very rapid occlusion. This will become the focus of the strongest winds with reinforcements rotating around the southern quadrant of the low into the dry slot feature.

Strong mid-latitude cyclones have eye features so the process will be for the eyewall to lose its localized intensity, rather than for the eye to disappear. I am almost certain there would be an eye visible in the storm as far north as 55N or beyond.

savj2

M.T. Cranium

The 06z GFS is very intense but not quite on the same track as other models, brings the strongest winds across outer Kerry then along Clare and Galway coasts. Pretty much the same track as Debbie took in 1961. Localized level 3 alert material with widespread level 2 south coast and inland.

Places like Newport, Westport and Clifden are now in a situation where a track difference of 30-50 miles could mean a huge difference in wind speeds, but Kerry, Clare and Galway (city) appear to be more certain to see severe winds. Cork to Limerick quite likely but some model tracks worse than others for them.

I have not seen any guidance yet that would be much more than 60 knot gusts for Dublin which is bad enough, but so far not a major impact.

Plenty of time for details to change and entire country needs to be on high alert.

Meteorite58

As above

davo2001

Is the above gusts or sustained wind speeds?

savj2

Meteorite58 wrote: »

As above

Sustained kph I think

smodgley

Would it be advisable to close schools yet especailly the rural ones as travel will be dangerous if event happens ?

Meteorite58

davo2001 wrote: »

Is the above gusts or sustained wind speeds?

gusts

pad199207

Meteorite58 wrote: »

gusts

We have had worse in these parts

Meteorite58

All charts subject to change but an idea of what it could look like

hatrickpatrick

davo2001 wrote: »

Is the above gusts or sustained wind speeds?

savj2 wrote: »

Sustained kph I think

Wind gusts and barbs, in knots per hour or kts (not to be confused with km per hour, which I think is what kph means)

Meteorite58

National Weather Warnings

STATUS YELLOW

Weather Advisory for Ireland
On Monday, an Atlantic storm from the remnants of Hurricane Ophelia will move northwards close to Ireland. There is still a high degree of uncertainty regarding the exact track and evolution of the storm. However, storm force winds, heavy rain and high seas are threatened. Met Eireann will continue to monitor this storm and will issue appropriate warnings as required.

Issued:Friday 13 October 2017 08:00
Valid:Monday 16 October 2017 06:00 to Tuesday 17 October 2017 06:00

savj2

hatrickpatrick wrote: »

Wind gusts and barbs, in knots per hour or kts (not to be confused with km per hour, which I think is what kph means)

Thanks. Wasn't sure.

Coax

smodgley wrote: »

Would it be advisable to close schools yet especailly the rural ones as travel will be dangerous if event happens ?

Yes it would.

There is a framework in place for this but I feel it needs improvement.

Meteorite58

https://twitter.com/weerenradar/status/918787123423178753

Meteorite58

10m wind speeds (kt)

Kermit.de.frog

A little bit of weakening of intensity in the projections but the zone of potential disruption is a bit wider too.

Still changes to come.

Iancar29

Friday midday and the forum is buzzing! :pac:

Storm 10

Surprised that ME would not at least have an Amber warning in place, they put up yellow for a small Gale yet they are saying storm force winds for Monday.

irish1967

Guess it’s time for my first visit since last winter. Hello from Donegal. 10meters from shoreline of Donegal Bay. 🌊

MJohnston

Storm 10 wrote: »

Surprised that ME would not at least have an Amber warning in place, they put up yellow for a small Gale yet they are saying storm force winds for Monday.

People were saying that it's about how far out the storm is - that even if nothing changes with the predictions by tomorrow that they'll bump it to an Orange warning or perhaps higher.

jasper100

Storm 10 wrote: »

Surprised that ME would not at least have an Amber warning in place, they put up yellow for a small Gale yet they are saying storm force winds for Monday.

Bit early putting out warnings for something that may miss us by 100 miles.

They have flagged that a storm is a distinct possibility but I don't expect them to make rash calls prematurely.

my3cents

jasper100 wrote: »

Bit early putting out warnings for something that may miss us by 100 miles.

They have flagged that a storm is a distinct possibility but I don't expect them to make rash calls prematurely.

But do you believe it will miss us by 100 miles?

Malayalam

Iancar29 wrote: »

Friday midday and the forum is buzzing! :pac:

I have the page open and regularly refreshing...weather possibilities like this brings out the islander in us all I think.

jasper100

my3cents wrote: »

But do you believe it will miss us by 100 miles?

I don't know, we will have to wait and see. But there is, from what I can see, still a good chance that this could be a damp squib causing minimal damage.

MJohnston

jasper100 wrote: »

Bit early putting out warnings for something that may miss us by 100 miles.

They have flagged that a storm is a distinct possibility but I don't expect them to make rash calls prematurely.

That's reasonable enough, but there is some context to consider here - for example the schools may not have enough time to react if a Red warning is put out over the weekend, and then come Monday they'll have to scramble. Same with elderly folks picking up the correct supplies.

Nothing might come of this, but if ME are still being vague about this tomorrow, I would consider that more reckless than putting out an 'overhyped' warning.

Gaoth Laidir

Latest visible satellite image and recent SSMIS 37GHz microwave image, showing it losing the western half of its eyewall.

pad199207

Gaoth Laidir wrote: »

Latest visible satellite image and recent SSMIS 37GHz microwave image, showing it losing the western half of its eyewall.

EWRC?