nav[aria-label="Primary Navigation"] { padding: 0; & ul { list-style: none; width: 100%; display: flex; flex-direction: row; justify-content: start; align-items: start; gap: 30px; padding: 0; & li { margin: 0; } & ul li { list-style: none; } } }

Child Item

Storm Ellen - 19th/20th August 2020

M.T. Cranium

I just finished my forecast prep and discovered that various models are toying with strong developments in the Biscay region within 24-36 hours affecting some parts of Ireland within 36-48 hours, but details vary from model to model so at this early stage it's not possible to give a very precise alert for which regions may see the strongest winds.

The developments are somewhat similar to a near-tropical storm scenario that I recall from this time of year several years ago. That one moved into the Irish Sea.

Impacts are likely to be winds of at least 60 to 90 km/hr and possibly a lot stronger than that, possibly in more than one wave around Thursday and Friday, and locally intense rainfalls rapidly increasing in totals to reach 30-50 mm.

My expectation is that some clarity and model consensus may emerge as early as the 12z model runs later today but it may not be that straight forward.

At the moment, the ECM seems to favour the southwest for peak development while the Arpege model favours the southeast. While the GFS and some other models have considerable wind and rain in their output, they don't necessarily pick up on these particular developments from Biscay, keeping more of a southwesterly origin for their trajectory and no discrete lows.

This may of course be a false alarm so at the moment I am going with a level 1 tag although if some maps verify we will definitely be seeing level 2 impacts at least.

Heavy rainfalls over several days will be falling on top of considerable rainfall that hit similar areas in recent days and this needs to be factored into flooding potential.

Find more posts tagged with

Quick Links

Comments

Graces7

adocholiday wrote: »

Slightly off topic but anyone know who you would call in the event of a tree falling down across a road? I have a number of mature trees all in leaf abutting a public road and any of them coming down would need emergency removal. Like is it a call emergency services situation? I've had a google but can't find anything on it.

999 is correct as it is a road threat. They will alert anyone who need alerting.

froog

Graces7 wrote: »

Good morning everyone. Although age-related health issues prevent my erstwhile participation, there is only one place to get up to date accurate info in weather like this. boards ie weather forum.

( I strive to keep my weblog alive as that covers weather, gardening, cats and many other aspects of island life)

Good to see familiar "faces"

All very quiet out here but darkening. Utterly silent. Ominous.

I read eg "Highest Astronomical tide" on reports.

I have seen the roads to the slipway flooded in "ordinary" "spring tides" so this is going to be phenomenal.

We are safe here; they all had the sense to build well above any possible tide reach. ( Fingers crossed!) and no real trees etc. And I have seen so many storms through in my years here. And never any damage done.

Stay safe!

Welcome back and glad you are well.

nthclare

juneg wrote: »

I saw those tents last week. Thats a wild spot to be in a storm. I hope they move.

I know it well enough,if it's coming from the east it'll blow down those hills behind and scoop up anything like a tent in second's.
While blowing onshore it's easier to get shelter from behind rocks etc...

munsterlegend

adocholiday wrote: »

Slightly off topic but anyone know who you would call in the event of a tree falling down across a road? I have a number of mature trees all in leaf abutting a public road and any of them coming down would need emergency removal. Like is it a call emergency services situation? I've had a google but can't find anything on it.

Your local authority should have an emergency number.

Graces7

Good morning everyone. Although age-related health issues prevent my erstwhile participation, there is only one place to get up to date accurate info in weather like this. boards ie weather forum.

( I strive to keep my weblog alive as that covers weather, gardening, cats and many other aspects of island life)

Good to see familiar "faces"

All very quiet out here but darkening. Utterly silent. Ominous.

I read eg "Highest Astronomical tide" on reports.

I have seen the roads to the slipway flooded in "ordinary" "spring tides" so this is going to be phenomenal.

We are safe here; they all had the sense to build well above any possible tide reach. ( Fingers crossed!) and no real trees etc. And I have seen so many storms through in my years here. And never any damage done.

Stay safe!

adocholiday

Slightly off topic but anyone know who you would call in the event of a tree falling down across a road? I have a number of mature trees all in leaf abutting a public road and any of them coming down would need emergency removal. Like is it a call emergency services situation? I've had a google but can't find anything on it.

munsterlegend

[Deleted User] wrote: »

Based on current model variance - something after noon tomorrow when we can see the trail of destruction

The afternoon/evening runs should be more specific and in line with each other. Of course that’s a bit late for a lot of people.

[Deleted User]

screamer wrote: »

Any idea when there will be more certainty around track and intensity?

Based on current model variance - something after noon tomorrow when we can see the trail of destruction

munsterlegend

KingdomRushed wrote: »

The ECM is very strange. Certainly you would have to take a view historically that it is unlikely such winds would occur in August.

In fact the scenario shown in the ECM this morning would result in massive economic damage, loss of life and unprecedented impacts on agriculture such as apple orchards and other crops.

Are the hi res models at this stage more reliable? ECM as others have said is probably overdoing it.

KingdomRushed

The ECM is very strange. Certainly you would have to take a view historically that it is unlikely such winds would occur in August.

In fact the scenario shown in the ECM this morning would result in massive economic damage, loss of life and unprecedented impacts on agriculture such as apple orchards and other crops.

screamer

Any idea when there will be more certainty around track and intensity?

Meteorite58

Uncertainty abounds. Will it shift more easterly I am wondering.

EURO 4 more like AROME

Reckless Abandonment

As a weather geek I love a good storm. As a gardener I'd prefer it not to be in the summer. Wind speeds anywhere near what MT/GL are talking about will do alot of damage to trees not to mention my sunflowers:( I'd advise moving anything in pots to a sheltered area

lolokeogh

Cheers for the updates and info folks..much appreciated

Gaoth Laidir

00Z UKMO analysis shows Ellen as a 999-hPa low just north of the Azores. By 00Z tonight they have it 966 hPa centred near Limerick, with the strongest gradient along the south and east.

The ECM is on steroids, with both the 18Z and 00Z runs both identical and showing a 1961 Debbie event, but it's also supported (to a lesser extent) by the Australian and GEM, which also show the >140-kph gusts along the south and east coasts. The ICON and GFS having none of it.

The discrepancies are most likely due to the complex setup and lack of aircraft upper-air data. The ECM forecast sounding show what appears to be a stingjet, with dry mid-levels, indicative of subsiding stratospheric air, but the speeds it's showing just don't seem reasonable at all. I would imagine a model consensus will be where things lie, with 130-140 kph into the south and southeast coast tonight, followed by 120-130 along the west coast tomorrow morning. 90-110 possible overland Leinster.

Here are the 00Z ECM run's gusts for the laugh...

M.T. Cranium

I took a weighted average of all guidance by reliability factor and the track is something like central Waterford for landfall to Leitrim and Donegal. The range (and not all models develop a separate low) is west coast to Wales. The maximum gust potential ranges from 60 to 130 km/hr.

The current location of developing centre is about 44N 16W.

Rainfall impacts could be underplayed so far, some local rainfall amounts over three days could be in the 70-100 mm range. In general terms, midlands, southwest and west are at most risk for flooding but there is one interval when east coast has heavy rain potential (late Friday). It could develop that tonight favours the east also but sometimes the heaviest rains with a tropical storm type of event are on the west side of the track.

munsterlegend

KingdomRushed wrote: »

More easterly impacting in my view this morning. Winds less severe but bigger impact for Dublin, Wicklow, Wexford

Thought these usually track more west!

KingdomRushed

More easterly impacting in my view this morning. Winds less severe but bigger impact for Dublin, Wicklow, Wexford

munsterlegend

DOCARCH wrote: »

Mod Note: Some earlier off topic posts removed (about a particular poster).

Just to say that the particular poster was never yellow or red carded in the weather forum!

Please keep discussion on topic....abut the weather. Thanks.

Thank grace I mean god for that.

Seems still a lot of uncertainty. Met Éireann latest forecast on website very general with little specifics as to wind speeds.

DOCARCH

Mod Note: Some earlier off topic posts removed (about a particular poster).

Just to say that the particular poster was never yellow or red carded in the weather forum!

Please keep discussion on topic....abut the weather. Thanks.

Oscar Bravo

Shannon airport forcasting gusts up to 60 knots tonight. This,of course,can change in later TAF,s but that kind of wind would do damage at this time of year

BECMG 1922/1924 20035G60KT TEMPO 1922/2003 4000 RA BKN010

M.T. Cranium

The GFS (00z) has shifted about halfway towards the European models with stronger more discrete solutions. It still does not depict an entirely separate low but has a track closer to Ireland (just off the east coast) with similar timing only further east. Canadian (GEM) shows a low of only moderate intensity tracking similar to the Arpege stronger solution. Various other takes from the model suite, nothing too convincing about any of them really.

The actual low is moving steadily along and has reached about 42N 17W with a turn to the northeast becoming more apparent. No pressure falls at 00z compared to 18z (still around 1002 mbs) so current pressure is likely just around or slightly under 1000 mbs. I don't see any explosive development signs yet.

The K1 ocean buoy (in the path around 15z) has unfortunately gone off-line so we will have to hope for some timely ship reports.

Kia_Kaha

sullivlo wrote: »

In all seriousness,what impact will the forecast likely have on the Dublin-Holyhead ferry? Relative booked to sail Thursday morning.

I'd recommending keeping an eye on the latest sailing updates on the ferry company websites - I had a crossing booked with Stena last december that was cancelled 3 days running due to bad weather, they usually update the information regularly, but you never really know until 6 hours out how bad the wind will be. Generally speaking that particular crossing is not often cancelled, the sea there isn't terribly exposed to the Atlantic, unlike the Rosslare > Fishguard/Pembroke Dock route however, which I suspect will be a different story as that part of the sea is much more exposed to Atlantic storms.

juneg

nthclare wrote: »

If this is blowing offshore, maybe whomever is camping along that stretch between Lisdoonvarna and Fanore should pack up and leave.

Because if a heavy gust catches some of those tents they'll be rolled over the cliff's in Ballyreen.
Straight into the brinny.

I saw those tents last week. Thats a wild spot to be in a storm. I hope they move.

sullivlo

piplip87 wrote: »

A storm of this potential in August imagine if there was no COVID. Imagine the amount if my flight is leaving dublin at 5PM will it be windy posts

In all seriousness,what impact will the forecast likely have on the Dublin-Holyhead ferry? Relative booked to sail Thursday morning.

Rougies

SleetAndSnow wrote: »

Usually these storms do tend to go further west then forecast don't they? Which is leaning me towards the ECM, UKMO type track rather then the AROME etc and it seems even Met Eireann is using the ECM track Vs their harmonie one which has the strongest winds further east it seems.

The typical late autumn and winter storms do tend to track further west than modeled relative to the intensity, we've seen that many times alright. This is a not a typical storm though so we don't really have a historical trend to help.

It's basically a weather model battle royal.

Mount Vesuvius

https://www.met.ie/forecasts/meteorologists-commentary

There is still a high degree of uncertainty in the exact track of the storm and there is a considerable spread in possibilities over Ireland with some models indicating that the east may get the strongest winds. The warnings will be updated Wednesday morning but here is the 18Z run of the Met Éireann high-resolution model, HARMONIE. It is an ensemble prediction system (IREPS) with 11 different possible tracks and outcomes. Orange level impacts may potentially occur over any part of the Island.

With trees in full leaf and peak numbers on holidays in Ireland, impacts could be significant with damaging winds, heavy rain, and large waves along the coast. Strong winds overland, high, potentially dangerous, waves can occur on lakes as well as along coasts and over high ground.

SlowBlowin

Shannon radar off again - lets hope its back in time for the storm if it shows...

smellyoldboot

Will we get a decent bang off it in Waterford?

[Deleted User]

piplip87 wrote: »

A storm of this potential in August imagine if there was no COVID. Imagine the amount if my flight is leaving dublin at 5PM will it be windy posts

Speaking of which... I have to drive around my house to get to work. Will I be able to get home safely?