Heavy Rain & Continuing Flood Risk - Saturday Dec 12th, 2015

Kermit.de.frog

This is looking quite bad for areas where flooding has already been an issue, especially in the southern half of the country, and where water tables are full.

Both Saturday and Sunday see heavy persistent pulses of rain push up across the southern half of the country in particular as a warm front stalls over the country.

This is already being flagged in southern parts of the UK too.





Take note. More later.

Wanderer78

jebus, what a disaster for flooded areas!

arctictree

I'm still worried about the forecast for Saturday morning as I have to drive over the Wicklow gap at 8am! Its looking increasingly dodgy.

Mars Bar

I'm supposed to be travelling to Belfast on friday and back on Saturday. What are the opinions on such long travel? I was gonna go through castlerea and up but now it looks like the motorway to Dublin and up will be the better option.

cherryghost

Weekend accumulations of 100-120mm forecasted in upper regions. We slowly approaching record rainfalls at some stations and it'll only be halfway through the month next week.

leahyl

cherryghost wrote: »

Weekend accumulations of 100-120mm forecasted in upper regions. We slowly approaching record rainfalls at some stations and it'll only be halfway through the month next week.

What about lower regions?

cherryghost

leahyl wrote: »

What about lower regions?

At the moment South, Southwest and Southeast look to be affected the most. Localized fall in Cork around 80mm.

Too early to call anything yet.

leahyl

Thanks Cherryghost,

That would be disastrous for Cork, I'll be keeping a close eye on it in the next few days.

patneve2

Looks very worrying according to the latest GFS. +24 hrs of constant moderate to heavy rain over the South.

cyclops999

cherryghost wrote: »

At the moment South, Southwest and Southeast look to be affected the most. Localized fall in Cork around 80mm.

Too early to call anything yet.

Press Release – River Shannon in the Athlone Area

Westmeath County Council

2:30pm Wednesday 9th December 2015

Water levels in the River Shannon are continuing to rise slowly and are being monitored by Westmeath County Council. Over the last 24 hours, water levels increased by approximately 70mm and to date, no houses have been flooded.

The Council is now in receipt of an updated ESB forecast of river levels for the next five days and that forecast is that water levels will reach 39.60mOD by Monday 14th of December 2015. It should be noted that this represents an increase of 390mm above current levels and would be close to the maximum level recorded in 2009.

Westmeath County Council has activated its Flood Emergency Response Plan and a meeting of the interagency Response Committee is held each day at 11am. At today’s meeting, chaired by Westmeath County Council and attended by representatives of An Garda Siochána, Irish Water, the Defence Forces and the HSE, it was agreed that the agencies would continue to assist people to protect their homes and businesses, to provide transport where this is required and to provide other humanitarian assistance.

A further update will issue after the meeting of the coordination committee tomorrow morning.

maquiladora

12Z GFS wants to put the south of the country under water. This would be major, widespread flooding. Of course the changes from run to run mean nothing is nailed down and a modest shift southwards would keep these fronts off shore. But this is what the 12Z GFS is showing.

This is considerably more than what the same model showed for rain totals from Desmond last weekend.

leahyl

Seriously scary stuff.....it's not that far away really

km79

maquiladora wrote: »

12Z GFS wants to put the south of the country under water. This would be major, widespread flooding. Of course the changes from run to run mean nothing is nailed down and a modest shift southwards would keep these fronts off shore. But this is what the 12Z GFS is showing.

This is considerably more than what the same model showed for rain totals from Desmond last weekend.

keep going south
good girl

Kermit.de.frog

I suspect, should things remain as forecast, there would be a red warning for flooding in the south.

Oneiric 3

EMHI 12z run has this feature just coming into the frame by 6pm Fri, and does appear to be making a beeline for the SW & South at this stage which would be concerning for sure.

maquiladora

munsterlegend

The ECM is not predicting such a doomsday scenario for rain though?

Iancar29

munsterlegend wrote: »

The ECM is not predicting such a doomsday scenario for rain though?

No but could all change on the 12z rolling out shortly.

km79

Iancar29 wrote: »

No but could all change on the 12z rolling out shortly.

fingers crossed it doesn't !

maquiladora

ECM at 72 hours looks almost identical to the GFS at 66 hours.

The rain may enter slightly further north on the ECM but other than that I think that initial phase of heavy rain at least is nailed now.




But by 96 hours....differences.

Duvetdays

Seriously can you not bring some good news for once!
As much as I love snooping around the weather forum particularly when there's an alert in place this is getting a bit much. Hopefully this doesn't add more misery to the people already affected by the flooding.

leahyl

maquiladora wrote: »

ECM at 72 hours looks almost identical to the GFS at 66 hours.

The rain may enter slightly further north on the ECM but other than that I think that initial phas

But by 96 hours....differences.

What do you mean by last line Maq?

maquiladora

leahyl wrote: »

What do you mean by last line Maq?

ECM and GFS handle the low differently by 96 hours, so there would probably be big differences on rainfall amounts and locations by this time.

It just shows there is still a good bit of uncertainty beyond 72 hours.

Oneiric 3

ECM 12z for Saturday noon.

km79

Oneiric 3 wrote: »

ECM 12z for Saturday noon.

crap
further north ?

JanuarySnowstor

Added to the rain Corks problem will be low pressure centred off the coast meaning Easterly winds.
Locals in Cork know an East wind stops the tide leaving through the estuary and basically backs up.
Coinciding with high tides and the ESB releasing water daily from the dam.

IF it were to play out as gfs suggests a red warning is a cert and is potentially v serious for Cork and indeed all of the South and West

Oneiric 3

km79 wrote: »

crap
further north ?

The heaviest rainfall (greens) still look to heading into Munster/S.Leinster but hard to judge at this point. Icelandic output should be updated by 7.05pm for a clearer picture.

http://www.vedur.is/vedur/sjovedur/atlantshafskort/#teg=atlant_hiti

maquiladora

km79 wrote: »

crap
further north ?

Yes, the heavy rain on Saturday enters further north on the ECM. The west and northwest getting the majority of it. Then out to the west the low starts to spin up and very slowly move eastwards bringing bands of rain over the country on Sunday and Monday, though less intense than Saturday.

So still a lot of uncertainty.

Oneiric 3

RTE weather on now. Potential for sleet and snow with this front on Saturday. :eek:

Siobhan Ryan didn't dwell too much on Saturday's potential, I suppose because of the high uncertainty at this stage.

maquiladora

Oneiric 3 wrote: »

RTE weather on now. Potential for sleet and snow with this front on Saturday. :eek:

Siobhan Ryan didn't dwell too much on Saturday's potential, I suppose because of the high uncertainty at this stage.

Yeah, precip on the the 12Z ECM at 75 hours is shown as snow over Galway/Mayo on the Weather Underground.

leahyl

Ok, so still very uncertain, the heaviest rain could end up missing the south?

MoodeRator

The UK Met Office seem confident of snow down South HERE

Oneiric 3

maquiladora wrote: »

Yeah, precip on the the 12Z ECM at 75 hours is shown as snow over Galway/Mayo on the Weather Underground.

RobertKK

If the high ground in the southern half of the country got that as snow...I could open a ski resort. They say midlands, north and west, maybe from north Kilkenny, Tipperary northwards for snow?

Though if there was heavy snow it would be even worse if it stayed on high ground and melted with heavy rain to make floods worse.

maquiladora

RobertKK wrote: »

If the high ground in the southern half of the country got that as snow...I could open a ski resort. They say midlands, north and west, maybe from north Kilkenny, Tipperary northwards for snow?

Though if there was heavy snow it would be even worse if it stayed on high ground and melted with heavy rain to make floods worse.

There will be a big temperature difference. Very mild, moist air in the south running into colder air further north. No snow in the south with these double digit figures!

Oneiric 3

As Maq said, ECM has the heaviest of the rain moving more into Connacht on Saturday, but can't say I am convinced about this solution, mainly because the GFS, having not only picked up on this potential before the ECM did, has also been more consistent with rainfall distribution from this feature.

RobertKK

maquiladora wrote: »

There will be a big temperature difference. Very mild, moist air in the south running into colder air further north. No snow in the south with these double digit figures!

maybe I was 15 miles out :P

I hope it is mild, have a lot of outdoor work whether it is rain, sleet or snow.

maquiladora

Met Office seem to be going with the GFS track, for now at least.

Hopefully this time tomorrow we'll have a better idea.

Villain

The ECM wasn't on board for this going beyond southern coastal counties this morning but certainly coming more inline with GFS, mind you the Met Eireann forecast updated in last 30 mins hasn't changed for Saturday really:

Saturday: Cloudy over south Munster and south Leinster with outbreaks of rain on Saturday morning and cold and frosty with icy patches elsewhere. The band of rain in the south may move northwards and turn to sleet or snow for a time. Frost is likely again in northern parts on Saturday night, but it will become milder in the south.

Villain

Net weather rainfall accumulation charts:

RobertKK

Looking very serious for southern areas that are prone to flooding, if these weather models are correct.

pad199207

The Liffey, Slaney, Barrow, Suir, Nore, Lee and Blackwater will all be on watch this weekend!

All very reminiscent of 2009. Flooding started off in the west and gradually the rest of the country followed!

Oneiric 3

UKMO Prep accumulation up to Sat 12z. Also going with the more southerly theme. ECMWF standing alone on this one for now.

km79

GO SOUTH
VERY VERY FAR SOUTH

WheatenBriar

pad199207 wrote: »

The Liffey, Slaney, Barrow, Suir, Nore, Lee and Blackwater will all be on watch this weekend!

All very reminiscent of 2009. Flooding started off in the west and gradually the rest of the country followed!

And the Avoca!

Oneiric 3

Weather coming up on RTE 1 in a couple of minutes.

leahyl

She's playing it down a little bit, just that it's going to be wet and windy, no mention of amounts of rainfall.

Oneiric 3

leahyl wrote: »

She's playing it down a little bit, just that it's going to be wet and windy, no mention of amounts of rainfall.

She mentioned that Saturday is looking potentially problematic. Seems a high degree of uncertainty so they have to cautious about alarming people.

leahyl

Oneiric 3 wrote: »

She mentioned that Saturday is looking potentially problematic. Seems a high degree of uncertainty so they have to cautious about alarming people.

I missed that part, think my mum started talking!

PukkaStukka

Talk of sleet and snow for most of the country on Saturday...:D

km79

PukkaStukka wrote: »

Talk of sleet and snow for most of the country on Saturday...:D

which will turn to water very quickly with the rain after
it's all precipitation
need dry weather
badly