Snow Ice Warning for Ireland 29 Jan to 03 Feb 2019 *See Mod Note in OP *

mickger844posts

Looking at the 11pm reports from Met Eireann obs stations Cork Airport, Roches Point, Sherkin and Valentia all in positive temps so that slightly milder air is
arriving. The deep cold in other area's may aid snow chances tomorrow but all so so marginal. We will see

Oscar Bravo

Belfast Aldergrove airport -3 @ 1120pm with a dew point of -4. nice.

11pm Met reports

Mullingar -4
Moore park -3
Mount Dillon -3
Oak Park -3
Phoenix Park -3

(Met eireann forecast on Rte Radio 1 @ 1155pm for the latest)

Gaoth Laidir

mickger844posts wrote: »

Looking at the 11pm reports from Met Eireann obs stations Cork Airport, Roches Point, Sherkin and Valentia all in positive temps so that slightly milder air is
arriving. The deep cold in other area's may aid snow chances tomorrow but all so so marginal. We will see

But then you have Waterford Airport at temp -4, dp -5!

Rebelbrowser

mickger844posts wrote: »

Looking at the 11pm reports from Met Eireann obs stations Cork Airport, Roches Point, Sherkin and Valentia all in positive temps so that slightly milder air is
arriving. The deep cold in other area's may aid snow chances tomorrow but all so so marginal. We will see

Im in Rochestown in Cork and it is rock solid frozen out there. Thermometer I have that usually matches Cork airport is still reading -3. Bit of a snowfield effect going on generally I think as most of Cork, other than roads, is still covered in a thin layer of snow / frozen slush.

mickger844posts

Gaoth Laidir wrote: »

But then you have Waterford Airport at temp -4, dp -5!

Surprising that reading considering how close it is to the coast and comparing with other stations in Waterford which are averaging around -2

Rebelbrowser

I'm beginning to think this could get interestingðŸ˜႒

Call me Al

I'm in South East Meath and my weather app is @ -3° right now.
DP of -4° but no precipitation due until 10am

mickger844posts

Rebelbrowser wrote: »

I'm beginning to think this could get interestingðŸ˜႒

It was always interesting but tomorrow model watching will mean nothing and now casting will reveal all. Still all outcomes on the table for many.

Danno

Now -4.7c on the AWS, skies clear with stars shining brightly.

Awaiting the 11.55pm Met Eireann broadcast.

South Laois 89m.

Speak Now

mickger844posts wrote: »

Surprising that reading considering how close it is to the coast and comparing with other stations in Waterford which are averaging around -2

Rural location Mick, always reads lower than you on clear nights.

Danno

-6c lows - Siobhan Ryan. (revised from -5c)

Moderate accumulations low areas possible.

Also, possible warning upgrade.

Oscar Bravo

Possible upgrade on warnings in the morning. Met eireann on Radio 1 just now.

aisling86

Rebelbrowser wrote: »

Im in Rochestown in Cork and it is rock solid frozen out there. Thermometer I have that usually matches Cork airport is still reading -3. Bit of a snowfield effect going on generally I think as most of Cork, other than roads, is still covered in a thin layer of snow / frozen slush.

My parents live in rochestown & over the past 30yrs when it freezes it freezes bad especially up the hills. I remember getting iced in for days.

pad199207

HUGE NEWS

Finally broke through -2.3c

-2.4c now

Kermit.de.frog

mickger844posts wrote: »

It was always interesting but tomorrow model watching will mean nothing and now casting will reveal all. Still all outcomes on the table for many.

Speak Now

The south east flow is going to kill low ground chances for most. After it pivots and the flow goes northeast there will be snow as it clears. By then I'll be sick when I think of all the rain that fell before hand. Could have been an epic slider if the front hadn't gone as far north.

aisling86

Kermit.de.frog wrote: »

I'm never going to sleep now bring it on!

Fakediamond

57495646-2EE6-496F-B14E-3F6525B332CA.png

Gaoth Laidir

mickger844posts wrote: »

Surprising that reading considering how close it is to the coast and comparing with other stations in Waterford which are averaging around -2

Wind is northeasterly so off the land.

pad199207

-2.7c now here

M.T. Cranium

People were talking about the role of lakes in generating snowfall. With a cold, dry flow across lakes of that size, some minor lake effect streamers can be generated. Lough Neagh is roughly the size of Lake Simcoe north of Toronto. I have seen situations where Lake Simcoe generates its own squalls from north winds that have not crossed Georgian Bay and these can drop 10 cms over small areas. Lough Derg and the lakes in Connacht are probably a bit too small to generate more than a few flurries.

However, this is a different situation where moist air in a synoptic scale precip shield is crossing these lakes. The factor in play then becomes more of temperature modification on western shorelines, if any, and it would seem in any marginal situation this could be a negative factor locally for snow generation but it is probably a rather minor consideration overall. (assuming these lakes are about 5-7 C they would slightly warm the boundary layer briefly).

Said I would add some details, but reading through the contributions in past few pages, I think the general ideas presented are sound and I don't need to add much. May have a better feel for the outcome by 0530h at forecast time, all depends on the fine tuning. Too bad this low didn't run into last March's cold air, then this would be a big event for sure. But I think it will be a significant event for some in Connacht and Munster, Leinster more of a question mark away from the usual higher ground jackpots. Somebody made a valid point about rainshadow effects downwind from Leinster high ground.

pad199207

M.T. Cranium wrote: »

People were talking about the role of lakes in generating snowfall. With a cold, dry flow across lakes of that size, some minor lake effect streamers can be generated. Lough Neagh is roughly the size of Lake Simcoe north of Toronto. I have seen situations where Lake Simcoe generates its own squalls from north winds that have not crossed Georgian Bay and these can drop 10 cms over small areas. Lough Derg and the lakes in Connacht are probably a bit too small to generate more than a few flurries.

However, this is a different situation where moist air in a synoptic scale precip shield is crossing these lakes. The factor in play then becomes more of temperature modification on western shorelines, if any, and it would seem in any marginal situation this could be a negative factor locally for snow generation but it is probably a rather minor consideration overall. (assuming these lakes are about 5-7 C they would slightly warm the boundary layer briefly).

Said I would add some details, but reading through the contributions in past few pages, I think the general ideas presented are sound and I don't need to add much. May have a better feel for the outcome by 0530h at forecast time, all depends on the fine tuning. Too bad this low didn't run into last March's cold air, then this would be a big event for sure. But I think it will be a significant event for some in Connacht and Munster, Leinster more of a question mark away from the usual higher ground jackpots. Somebody made a valid point about rainshadow effects downwind from Leinster high ground.

That was me always looking out for it setups like this be it rain or snow

Gaoth Laidir

I think this is the longest TAF I've ever seen. For Cork. Unfortunately no mention of snow at all. Similar with all the other airports. Only rain and sleet mentioned up to midnight tomorrow.

TAF EICK 302300Z 3100/3124 11007KT 9999 FEW015
PROB30 TEMPO 3100/3103 0500 FZFG
BKN002 BECMG 3103/3105 13012KT
BECMG 3105/3108 15016G27KT -RA SCT008 BKN015
TEMPO 3105/3113 4000 RA BKN008 SCT018CB
PROB30 TEMPO 3105/3108 2000 RASN BKN004
BECMG 3108/3110 15020G35KT
PROB30 TEMPO 3108/3110 15025G40KT 2000 +RA BKN004
BECMG 3110/3113 18015G28KT FEW010 SCT020
BECMG 3113/3115 11012KT PROB30
TEMPO 3113/3120 -RA BKN010
BECMG 3115/3117 05008KT
BECMG 3118/3120 08020G30KT
TEMPO 3120/3124 5000 -RA BKN008 FEW018CB
PROB40 TEMPO 3120/3124 2000 RASN BKN004=

pad199207

Just hit -3c now

Mortelaro

pad199207 wrote: »

Just hit -3c now

Hurry up there:D

munsterlegend

Gaoth Laidir wrote: »

I think this is the longest TAF I've ever seen. For Cork. Unfortunately no mention of snow at all. Similar with all the other airports. Only rain and sleet mentioned up to midnight tomorrow

Are those TAF forecasts then not completely at odds with what Siobhan Ryan said at 11 55 radio forecast?

tikkamark

-4 here in Meath right now.Hard to believe were going to be lashed out of it with rain tomorrow after a night as cold as this

sdanseo

Getting a tad nippy in Wicklow.

00:20 N81 Baltinglass [Road]-4.9°C [Air]-6.6°C 0 km/h NNW

sdanseo

Once again, GFS Parallel almost flawless with its temperature prediction. Significantly better than HIRLAM.
Top image what it shows for around now, compare with reports in last few posts.
2nd image what it says for tomorrow 7pm
3rd dewpoints tomorrow 7pm

For an air temp of 1° we want a DP of -1° minimum to be safe.

Gaoth Laidir

munsterlegend wrote: »

Are those TAF forecasts then not completely at odds with what Siobhan Ryan said at 11 55 radio forecast?

They're only valid for within a 5-mile radius of the airport, so not necessarily fully indicative of the larger region.