Storm Callum - Thursday/Friday 11/12 October 2018 **READ MOD NOTE IN FIRST POST**

Sycamore Tree

This storm got a mention in the Dail just now. Alan Kelly mentioned it in his budget response speech.

It could be the most high profile storm in years

Discodog

Really nice animation showing the storm & the jet stream.

https://earth.nullschool.net/#current/wind/surface/level/orthographic=-18.72,40.43,468/loc=-7.173,53.820

REBELSAFC

Discodog wrote: »

Really nice animation showing the storm & the jet stream.

https://earth.nullschool.net/#current/wind/surface/level/orthographic=-18.72,40.43,468/loc=-7.173,53.820

Lovely image but I think the storm there is Hurricane Lesley, not the yet to be named "Ferocious Friday"

dacogawa

REBELSAFC wrote: »

Lovely image but I think the storm there is Hurricane Lesley, not the yet to be named "Ferocious Friday"

Love "Ferocious Friday" We should get to name the storms on here!

The next one should be "Stormy McStormface"

An Ri rua

Unusual clear-lined ridges to the cloud structures rolling in across the Midlands this evening. Something tells me we're in for a humdinger of a storm. Even the crows and starlings are anticipating.

M.T. Cranium

You can tell the NHC are fed up with Leslie and now the GFS wants to take it back west for yet another grand tour. It may end up becoming one of the longest-lived tropical cyclones in the North Atlantic -- if you add its two appearances so far, 19-24 Sept and 28 Sept - present, total of 18 days and possibly another two weeks if GFS correct, so 32 days. Other models bring Leslie close enough to Iberia or Africa that it could dissipate there around Monday. That would be a 24 day life span and really in the four days it was "off the books" it was a strong extratropical cyclone so quite a long-lived storm (now reaching 22 days on that count).

The longest lived (according to Wikipedia) was a hurricane in 1899 that lasted for 27 days (at least TS level).

As for storms with two life cycles, those are fairly rare when separated by more than three days, more common for briefer downgrades, the main reason being travel over cooler mid-Atlantic waters removing tropical characteristics. Looks to me like Leslie is already near number ten on the all-time list. Link here:

https://en.wikipedia.org/wiki/List_of_Atlantic_hurricane_records

dacogawa

RTE went for it in the forecast there, wasn't expecting that!

Roll on the ECM...

Snowbiee21

Large uncertainty continues on the track of this coming Friday's potential storm and just how much of an impact it will have on Ireland. Current likelihood is for a very stormy start to Friday with strong gusts of wind to the same extent that Storm Ali was on the 19 September for many and even stronger in some more localised spots of the west especially the southwest. There is a chance of a window of drier, calmer weather through the middle of Friday before the day ends exceptionally wet into Saturday especially in the southeast of the country around Waterford, Wexford and Carlow.

This low has the potential to be named Storm Callum and it's being picked up by a very powerful jet stream (which drives all the low pressure systems to Ireland when they come here). Will it be another storm that never was like on Sunday 23 September? Not likely but we shall see, it's all up for grabs at the moment.

If current thoughts verify, parts of the west could receive a red status warning which will close businesses and schools. Other regions of the country like in the east (including Dublin in case people ask) are very unlikely to get a red warning, the highest as an amber warning. There maybe separate warnings for the heavy rain later in the day too.

Tomorrow will be a warm day in contrast with temperatures getting up to 18-20c widely over Ireland, highest in the east. It'll feel almost tropical if you catch any sunshine. Classic Indian Summer day. Calm before the storm as they say! Credit from the great SRYANBRUEN

goat2

Seems like a fast moving storm,

dacogawa

New ECM is out

ninebeanrows

Looks like a fish on the latest EC

We still have a very strong southerly to contend with though which will give a widespread yellow warning regardless of where the centre of the depression goes, possibly Orange warning in some coastal domains.

M.T. Cranium

So the ECM while very deep (948 mbs) still holds on to a glancing blow scenario with that track, would imagine still some level one winds between map hours around 03-06z if that verifies.

Similar differences in relation to Michael further west so the two things are connected.

No particular hunch here, hate it when mom and dad bicker.

uck51js9zml2yt

Looks like I'll get to feel what it looks like living half way up a mountain on the west coast very soon :eek:

I should have stayed in Dublin:D

sdanseo

Not to be sensationalist, but meanwhile, 12Z runs from every other model.

I wouldn't say we're completely out of the woods, although the ECM has been infinitely more reliable than GFS lately.
If the ECM correctly resolves this in the face of all of the below, it will be another very strong signal that it is becoming even more reliable at medium ranges.

GFS - 140-150km/h onshore gusts. Widespread if not national orange warning.



WRF - easily a red warning for the West on mean speed basis



ICON - always overcooks things a bit but nonetheless showing <170km/h onshore gusts



ARPEGE - up to 150km/h onshore and widespread 100-120km/h gusts.

pad199207

Nicholas Worried Goalkeeper wrote: »

Looks like I'll get to feel what it looks like living half way up a mountain on the west coast very soon :eek:

I should have stayed in Dublin:D

I’m in Achill Thursday and Friday :-o

Villain

ECMWF is holding firm!

https://twitter.com/carlowweather/status/1049728420240867328?s=21

SleetAndSnow

How do we look in Cork at the moment? Bit of an iffy county because its south, yet included in the south west at time and the south east at other times

sryanbruen

ECM 12z has even higher rainfall totals than previous runs but they're further eastwards into the west of the UK rather than the southeast of Ireland. Not nearly as wet for us as last night or this morning's ECM runs.

D9Male

Does the ECM still forecast torrential rain on Saturday for the South and East?

Ignore, answered above.

Artane2002

sryanbruen wrote: »

ECM 12z has even higher rainfall totals than previous runs but they're further eastwards into the west of the UK rather than the southeast of Ireland. Not nearly as wet for us as last night or this morning's ECM runs.

I think some people in the southeast could use up 15-30mm so that's good for them, not so good for the rain haters. I'm going to guess the ECM will be closer to the mark regarding winds because 9 times out of 10 the less extreme solution wins out.

Meteorite58

Clear difference in track between the ECM and the group of GFS, ARPEGE, ICON, WRF

Meteorite58

ECM less severe than the other models with the biggest winds out to sea, still clipping the SW fairly well on this run but short lived and strong along the W.

Widespread gusts over 100 km/h inland, over 110km/h in places

Held its track in two consecutive runs which is saying something. Will see if the others follow suit.

Chris_5339762

GFS Operational showing ridiculous amounts of sustained rain for Dublin.

Sycamore Tree

Meteorite58 wrote: »

ECM less severe than the other models with the biggest winds out to sea, still clipping the SW fairly well on this run but short lived and strong along the W.

Is ECM generally more reliable for these storm events?

Artane2002

Sycamore Tree wrote: »

Is ECM generally more reliable for these storm events?

GFS usually overdoes lows so I'd say it's slightly more credible than the GFS.

Meteorite58

Sycamore Tree wrote: »

Is ECM generally more reliable for these storm events?

One of the more reliable and realistic, not prone to overdoing it. Unusual though to see the others being so closely grouped. The ECM has a good record coming out on top over the other models in reliability scores.

The UKMO would seem to be further W as well .

xii

Why are ME worried this far out if the more reliable forecasts are showing a shift west. what do they use?

MJohnston

xii wrote: »

Why are ME worried this far out if the more reliable forecasts are showing a shift west. what do they use?

A version of the HARMONIE model that isn't available for public consumption, sadly.

Sycamore Tree

xii wrote: »

Why are ME worried this far out if the more reliable forecasts are showing a shift west. what do they use?

They might be erring on the side of caution after Ali.

thomil

MJohnston wrote: »

A version of the HARMONIE model that isn't available for public consumption, sadly.

I thought they were using a locally hosted HIRLAM instance for short range forecasts up to 48 hours, and rely on ECMWF for longer forecasts? Met Éireann is certainly listed as such on the HIRLAM consortium website.