Storm Dylan : Sat 30th PM / Sun 31st Dec 2017 AM

ninebeanrows

GFS has edged a bit further northwest

A severe storm

ninebeanrows

More impressive on the HIRES GFS- a dangerous storm approaches the west coast towards midnight....

Gaoth Laidir

Meteorite58 wrote: »

Anybody with any experience of how reliable the Europe Swiss HD 4 *4 ( 3 day Model ) , Europe HD Flash and Europe Britain HD are ? ( found on the weather.us site)

The Europe Swiss HD 4x4 is their hi-res COSMO model for Europe, the HD flash is I think the Hirlam and the Britain HD is the Euro4.

Meteorite58

Yes they are starting to align better I think.

Oscar Bravo

Mace Head around 0400 Sunday should be gusting fairly high!

Neddyusa

Which hi-res model had the positioning of this evenings weather fronts most accurately shown yesterday?

Answer might give an indication of which model is most reliable RE tomorrow nights path.

Meteorite58 wrote: »

Some split in the models, this could come down to the wire before the track is known proper ( if that is possible !)

I think the ARPEGE is probably too far North ?



The GFS possibly too far South ?



WRF again maybe too far South ?



Would lean towards the ECM as the most consistent over the last few days but maybe a track a bit more South ? ( cant upload the ECM charts atm )


ICON again taking it more South. Might be more towards this track or a bit further North ?

Meteorite58

Which hi-res model had the positioning of this evenings weather fronts most accurately shown yesterday?

Answer might give an indication of which model is most reliable RE tomorrow nights path.

I think the ICON had a better handle on it than the GFS or WRF, the HIRLAM has been quite consistent too.

Meteorite58

Going by the ECM 12Z pressure charts I make out that when the wave first makes an appearance in the 09.00 chart it has a reading of 990hPa and by the time it deepens to a storm off the W coast at 03.00 it has a reading of 957 hPa. That is a drop of 33 hPa in 18 hrs.

Explosive cyclogenesis otherwise known as a weather bomb I would think.

Jaycornyn

Is there a chance some counties might see a red warning by tomorrow evening?

Meteorite58

Jaycornyn wrote: »

Is there a chance some counties might see a red warning by tomorrow evening?

IMO if the storm's track brings the winds in over land then I think there is a good chance of a Red Warning for some counties.

stephenjmcd

With orange warning in effect from 9pm, and looking at the charts albeit at a very novice level, would I be right in saying perhaps red level for the West coast from say 11pm or around mid night until 9/10am ??

Meteorite58

Meteorite58

stephenjmcd wrote: »

With orange warning in effect from 9pm, and looking at the charts albeit at a very novice level, would I be right in saying perhaps red level for the West coast from say 11pm or around mid night until 9/10am ??

Met Eireann updated there forecast a bit : Saturday night will be wet and very windy after a mainly dry start. Storm Dylan will track close to Connacht and Ulster coasts overnight generating mean wind speeds of 60 to 80 km/hr with gusts of up to 120 km/hr in parts of Conancht and Ulster with the strongest winds in coastal counties. Please check Met Eireann website for updates of warnings in operation.


The timing something around then or a bit after. Met Eireann sticking to there guns for now, they have more time to see how this pans out I would say as it is happening overnight on a weekend so less traffic on the roads etc.

The models have changed their track more towards the ECM so important to see what it does on the next run which will be out in the morning for the public.

Rock Lesnar

Am i right looking at the chart above that north meath could take a bit of hit from this or am i reading it wrong

stephenjmcd

Meteorite58 wrote: »

Met Eireann updated there forecast a bit : Saturday night will be wet and very windy after a mainly dry start. Storm Dylan will track close to Connacht and Ulster coasts overnight generating mean wind speeds of 60 to 80 km/hr with gusts of up to 120 km/hr in parts of Conancht and Ulster with the strongest winds in coastal counties. Please check Met Eireann website for updates of warnings in operation.


The timing something around then or a bit after. Met Eireann sticking to there guns for now, they have more time to see how this pans out I would say as it is happening overnight on a weekend so less traffic on the roads etc.

The models have changed their track more towards the ECM so important to see what it does on the next run which will be out in the morning for the public.

That's what I was thinking with it being mainly an overnight event that they may not increase the warning to a red level.
Heading to Galway myself on the train tomorrow evening due in at 10 so that should be interesting

Meteorite58

Rock Lesnar wrote: »

Am i right looking at the chart above that north meath could take a bit of hit from this or am i reading it wrong

On the WRF model and on this run yes, I think the different models are getting more in line with the 12Z ECM . Met Eireann is still talking about Conancht and Ulster and they must have their reasons being the professionals ?

MJohnston

There's a secondary wind impact that potentially hits in some of the models around NYE 10pm that should be carefully monitored, I think - it could be a danger to folks out celebrating in the south-west. Saturday overnight will be less of a danger in a sense as a lot of people won't be out because of NYE.

M.T. Cranium

Dylan looks quite compact and the extent of severe gusts may be confined to exposed locations north of Galway Bay around to Malin Head with diminishing impacts further south and east.

I may change my view on that as the storm rapidly develops later today and we can get a better handle on details, but most of the guidance seems to indicate severe winds limited to those counties and in particular coastal Mayo, north Sligo/Leitrim and west/morth Donegal. Gusts to 70 knots or 130 km/hr could occur (0200-0500h).

Galway Bay might briefly see similar intensity when winds are due west but if the current guidance is correct, exposed locations in west Munster might peak closer to 55 knots, Dublin around 52 knots.

Will underscore the uncertainty in my forecast and alert readers to watch for updates -- but that's how I plan to start my forecast response.

Meteorite58

The ECM keeping the strongest winds along coastal counties in the W, NW and N. Perhaps some strong winds in the SW for a time. Seems to be the most consistent and accurate performing model.

Meteorite58

The other models have come more in line with the ECM. Still time for them to drift more N on next runs taking more of the stronger winds off shore.

Meteorite58

Met Eireann current forecast:Tonight, rain will spread northeastwards with strengthening south to southeast winds. From around midnight onwards, it will become stormy in the west and northwest with severe or damaging gusts of up to 120 km/hr. and very windy further east with very strong, gusty southwest winds.

Sunday morning will continue very windy or stormy over the northern half of the country with very strong, southwest winds and severe gusts of up to 120 km/hr. In the late morning and afternoon, winds will gradually ease from the west.

Oscar Bravo

Update 0800
STATUS ORANGE

Wind Warning for Connacht, Cavan, Monaghan, Donegal, Longford, Louth, Westmeath, Meath and Clare

Update of warning
Tonight and Sunday morning storm Dylan will track northeastwards close to Connacht and Ulster coasts. The biggest impact from the storm will be in western and northern counties with west to southwest winds reaching mean speeds of 65 to 80 km/h with gusts of 110 to 125 km/h. High seas along the west coast too with the risk of coastal flooding.

Issued:

Saturday 30 December 2017 08:00

Valid:

Saturday 30 December 2017 21:00 to Sunday 31 December 2017 10:00

dmc17

Fairly high tides and big swells off the west coast early Sunday morning also

JCX BXC

Clare added to the orange warning, fun

Debating whether or not to bring in my Davis, I'm not happy with its current setup.

squarecircles

Anticipating Dylans arrival tonight in West Mayo, we're well used to these winds though.

Any chance the wind gusts could go higher than 125 kmh ?

Gaoth Laidir

https://twitter.com/MetEireann/status/947059494441439233

amandstu

That latest MetEireann gif seems to be pushing the winds quite a bit further away from the West coast.

Seems to be very windy weather coming up a few days later though.

Gaoth Laidir

ICON seems to be overdoing the gusts a bit, with >160 kph at Belmullet.

Meteorite58

Interesting that the Met Office keeps the track closer to the coast.

https://twitter.com/metoffice/status/947062044611809281

Meteorite58

The 9Z Icon further off shore again.