Light Snow - Overnight Wed/Thu 6th/7th January 2021

Nqp15hhu · 06-01-2021 1:15pm

I have years of experience as well..

Your experience in another region doesn’t trump what the weather models show. Two of you now have referred to a northerly wind which is non existent on the models.

I have just posted charts to show a SW and WSW wind which the Met Office also forecast.

Either way, as I said earlier the issue will be the timing of precipitation, if it comes in before midnight it could fall as sleet or wet snow.

Danno · 06-01-2021 1:19pm

Nqp15hhu wrote: »

You are all determined that I won’t see snow.

Please pull back on the you V us tone, it's unhelpful.

Other posters here are highlighting what the charts are showing and showing you where the marginality of the setup in your area may mean you miss out on snow for some or all of the front's passage.

It's 50-50 in your area to see this completely fall as snow and accumulate.

Further inland behind the Sperrins to the south of you would be a much better location.

I hope for you that the winds continue SWly for a good proportion of the night.

highdef · 06-01-2021 1:21pm

Nqp15hhu wrote: »

Well I am not on the immediate coast. I am about 10 miles from the north coast.

I do have water to my NW but that only affects me with a WNW or NW wind which it is not going to be.

10 miles is not much when weather is coming in from the sea. Yesterday, Gonzo (who is located between 15 and 20 miles from the east coast) was getting sleety icy showers from the northeast. The very same showers were falling mainly as big fluffy flakes for me (still not sticking though) with a land track of almost 30 miles. We're both at similar altitudes. 50m higher, on the hill to my immediate northeast, snow was just about accumulating but that was close to 150m ASL. One needed to travel about another 30 miles west in order to get temperatures to be cold enough to support snow that would stick at low levels however at this point the showers would have all died out.

pauldry · 06-01-2021 1:24pm

Expecting this to fall as snow for a short period in Sligo and then turn back to rain. We are 5 miles from the coast so anything over 0c usually means rain or sleet. Best we can hope for is snowballs off the car tops

Donegal Ken · 06-01-2021 1:25pm

Highest snow amounts will be across Ulster moderate falls for a time across, Donegal, Derry, Cavan, Tyrone, Fermanagh, Leitrim, Antrim and Sligo accumulating betweeb 2cm to 5cm possibly eastern parts of Galway and Mayo also.
The above areas will sea a mix of sleet around the coasts.

Elsewhere amounts will be much lower 1cm to 2cm but parts of Munster, much of Leinster southern and western Connacht will see very little or nothing at all.

pauldry · 06-01-2021 1:26pm

The temperatures are all rising up a notch now. This could be concerning.

Nqp15hhu · 06-01-2021 1:29pm

highdef wrote: »

10 miles is not much when weather is coming in from the sea. Yesterday, Gonzo (who is located between 15 and 20 miles from the east coast) was getting sleety icy showers from the northeast. The very same showers were falling mainly as big fluffy flakes for me (still not sticking though) with a land track of almost 30 miles. We're both at similar altitudes. 50m higher, on the hill to my immediate northeast, snow was just about accumulating but that was close to 150m ASL. One needed to travel about another 30 miles west in order to get temperatures to be cold enough to support snow that would stick at low levels however at this point the showers would have all died out.

There is no wind coming off the ocean.

highdef · 06-01-2021 1:30pm

Nqp15hhu wrote: »

There is no wind coming off the ocean.

ECM suggests it will be around or shortly after midnight. It's usually one of, if not the most accurate and reliable model so I would not discount it.

Humberto Salazar · 06-01-2021 1:31pm

Looks weak on satellite, needs a bit of pepping up to deliver a couple cms even past the midlands.

Gaoth Laidir · 06-01-2021 1:40pm

Donegal Airport's TAF to 9 pm has it starting off as rain along the coast.

TAF EIDL 061100Z 0612/0621 16005KT 9999 BKN040 BECMG 0617/0619 BKN014 TEMPO 0619/0621 4000 -RA BKN009=

Airport warnings for Ulster airports (UKMO)

Derry Eglinton

Frost
Issued at: Wed 06 Jan 2021 - 11:32 UTC
Valid from: Wed 06 Jan 2021 - 18:00 UTC
Valid to: Thu 07 Jan 2021 - 00:00 UTC
GROUND AND AIR FROST IS LIKELY TO OCCUR. FROZEN DEPOSITS MAY FORM ON PARKED AIRCRAFT, RUNWAYS AND TAXIWAYS.

Frost
Issued at: Wed 06 Jan 2021 - 05:36 UTC
Valid from: Wed 06 Jan 2021 - 16:00 UTC
Valid to: Wed 06 Jan 2021 - 18:00 UTC
GROUND AND AIR FROST IS LIKELY TO OCCUR. FROZEN DEPOSITS MAY FORM ON PARKED AIRCRAFT, RUNWAYS AND TAXIWAYS.

Snow
Issued at: Wed 06 Jan 2021 - 11:32 UTC
Valid from: Wed 06 Jan 2021 - 21:00 UTC
Valid to: Thu 07 Jan 2021 - 00:00 UTC
SLIGHT RAIN AND SNOW MAY OCCUR AT THE AIRFIELD BUT NO SIGNIFICANT ACCUMULATIONS ARE EXPECTED.

Belfast Algergrove

Frost
Issued at: Wed 06 Jan 2021 - 12:03 UTC
Valid from: Wed 06 Jan 2021 - 16:00 UTC
Valid to: Thu 07 Jan 2021 - 11:00 UTC
A GROUND FROST IS LIKELY TO OCCUR. FROZEN DEPOSITS MAY FORM ON PARKED AIRCRAFT, RUNWAYS AND TAXIWAYS.

Frost
Issued at: Wed 06 Jan 2021 - 12:03 UTC
Valid from: Wed 06 Jan 2021 - 16:00 UTC
Valid to: Thu 07 Jan 2021 - 07:00 UTC
AN AIR FROST IS LIKELY TO OCCUR. FROZEN DEPOSITS MAY FORM ON PARKED AIRCRAFT.

Belfast City

Frost
Issued at: Wed 06 Jan 2021 - 11:33 UTC
Valid from: Wed 06 Jan 2021 - 18:00 UTC
Valid to: Thu 07 Jan 2021 - 00:00 UTC
GROUND AND AIR FROST IS LIKELY TO OCCUR. FROZEN DEPOSITS MAY FORM ON PARKED AIRCRAFT, RUNWAYS AND TAXIWAYS.

Frost
Issued at: Wed 06 Jan 2021 - 05:36 UTC
Valid from: Wed 06 Jan 2021 - 17:00 UTC
Valid to: Wed 06 Jan 2021 - 18:00 UTC
A GROUND FROST MAY OCCUR. FROZEN DEPOSITS MAY FORM ON PARKED AIRCRAFT, RUNWAYS AND TAXIWAYS.

Nqp15hhu · 06-01-2021 1:43pm

highdef wrote: »

ECM suggests it will be around or shortly after midnight. It's usually one of, if not the most accurate and reliable model so I would not discount it.

No it doesn’t.

Gaoth Laidir · 06-01-2021 1:47pm

09Z ICON Flash weather maps for 00Z to 12Z. Very light precip for most.

Gaoth Laidir · 06-01-2021 1:52pm

UKMO GAMET for northern UK, including NI. Giving isolated snow over land from 17Z.

Met Situation Valid at 1800 UTC
A GEN LIGHT W TO SW FLOW, BUT MOD TO STRONG IN FAR NW. TO W OF COLD FRONT, FLOW BECMG MOD TO STRONG NW.
COLD FRONT LIES N6200 W00300 TO N5800 W00500 TO BARRA TO N5500 W01100, MOV SE AT 5-10KT.

Freezing Level
GEN 1000FT, BUT LCA 500FT CENTRAL SCOTLAND, AND 2000FT NEAR COLD FRONT.

Weather Conditions
Zone 1
NW OF A LINE BELMULLET TO MALIN HEAD TO INVERNESS TO SHETLAND TO N6130 W00030, AND SE OF A LINE N5700 W01000 TO LEWIS TO N6100 W00500, BOTH LINES MOV SE AT 05-10KT:
GEN 15KM IN OCNL RA, WITH 1-4/8ST 800-1200FT/1500 AND 5-7/8CUSC AND ACAS 2000FT/14000.
WDSPR 6KM IN RA OR RADZ, WITH 3-6/8ST 600-800FT/1500 AND 7-8/8CUSC AND ACAS 1500FT/14000.
OCNL 3000M IN RADZ OR HVY RA, OR RASN LAN, WITH 5-7/8ST 600FT/1500 AND 8/8CUSC AND ACAS 1500FT/16000.
ISOL LAND SE FROM 17Z, 800M IN SN, WITH 5-7/8ST 500FT/1500 AND 8/8CUSC AND ACAS 1500FT/14000.
WRNG: HILL FG. MOD ICE AND MOD TURB IN CLD. SN MON ABV 1000FT.

Zone 2
SE OF ZONE 1, AND NW OF A LINE CORK TO DUBLIN TO ISLE OF MAN TO ALNWICK TO N5630 E00000, MOV SE AT 05KT:
GEN 30KM WITH 0-5/8CUSC 1500-3000FT/4000-6000.
ISOL LAN, 200M IN FZFG, WITH 7/8ST SFC/500-1000.
WRNG: HILL FG. MOD ICE AND MOD TURB IN CLD.

Zone 3
REST OF REGION:
GEN 25KM WITH 3-6/8CUSC 2000FT/6000.
ISOL 7KM IN SHRA OR SHRASN, WITH 0-4/8ST 800-1200FT/1500 AND 7/8CUSC 1500FT/8000-10000.
ISOL, 2000M IN SHRASN, WITH 2-5/8ST 500-800FT/1500 AND 7/8CUSC 1500FT/8000-10000.
ISOL LAN FM 18Z, 200M IN FZFG, WITH 5-7/8ST SFC/500-1000.
WRNG: HILL FG. MOD ICE AND MOD TURB IN CLD. SN MON ABV 500FT.

Danno · 06-01-2021 1:57pm

Nqp15hhu wrote: »

No it doesn’t.

Upper air (1500m) does show a NNW breeze for your area which may bring in enough of a marine layer wedged between the cloudbase and ground level. If this marine layer melts the snow it would give you sleet, as the lower layer containing a SWly airflow wouldn't be deep enough to turn it back to snow again.

06-01-2021 1:58pm

Nqp15hhu wrote: »

No it doesn’t.

On hirlam its n or ne by 2am
But the map is a mess
Its certainly sw before that

highdef · 06-01-2021 1:59pm

Nqp15hhu wrote: »

No it doesn’t.

Correct, it doesn't now. Latest run has the switch to the northwest occurring later in the night, around 3/4am however that was not what was being shown when I posted earlier. Your temperatures remain marginal though, depending on your exact location which I don't know.

Danno · 06-01-2021 1:59pm

Just to add, here is a decent demonstration of different layers moving in different directions:

https://www.youtube.com/watch?v=eAoBWRjdGpU

munsterlegend · 06-01-2021 2:08pm

Latest Harmonie from Met Éireann seems to keep front pretty much in tact coming down over the country. It’s on their twitter page.

Gaoth Laidir · 06-01-2021 2:22pm

Anyway...

It's unusual to see the Arpege also showing snow soundings, such as below for mid-Kildare at 6 am. It's a model that tends to have a warm bias when it comes to snow here.

kittyn · 06-01-2021 2:27pm

It would be lovely to wake up to a blanket of snow, and I think it would give the vast majority of the country a much needed lift and also keep travel to a minimum due to the nature of snow but hey mother nature will do what mother nature wants to do...... Who knows what will happen and that's half the fun of model watching

06-01-2021 2:37pm

kittyn wrote: »

It would be lovely to wake up to a blanket of snow, and I think it would give the vast majority of the country a much needed lift and also keep travel to a minimum due to the nature of snow but hey mother nature will do what mother nature wants to do...... Who knows what will happen and that's half the fun of model watching

I've a hunch with the length this lockdown is going to go on for that there will be a national snow event before its lifted
It all depends on where the pv and its daughters land
But that's for another thread and at least a week away before we have an idea

lolie · 06-01-2021 2:37pm

Danno wrote: »

In the snow starved years after 2001 until 2009 that was considered epic!

Epic could be pushing it a bit Danno but anything thats falls is welcome here.
I'm hoping tonight's snowfall is at least similar to early February 2009 when an inch or so fell from a front from the west.
That December 2000 snowfall really set us up for disappointment that decade.

Danno · 06-01-2021 2:44pm

lolie wrote: »

Epic could be pushing it a bit Danno but anything thats falls is welcome here.
I'm hoping tonight's snowfall is at least similar to early February 2009 when an inch or so fell from a front from the west.
That December 2000 snowfall really set us up for disappointment that decade.

Apart from a White Christmas 2004 that decade was a notable one for lack of snow and low temperatures in general.

It was close to epic with teary-eyed, fully grown men doing a snow dance in 2008.

:pac:

Rebelbrowser · 06-01-2021 2:51pm

AuntySnow wrote: »

I've a hunch with the length this lockdown is going to go on for that there will be a national snow event before its lifted

As in Jan or Feb 2023 say?

mickger844posts · 06-01-2021 2:53pm

Mod Note On topic and less confrontational going forward please. Thank

Rebelbrowser · 06-01-2021 2:56pm

Danno wrote: »

Apart from a White Christmas 2004 that decade was a notable one for lack of snow and low temperatures in general.

It was close to epic with teary-eyed, fully grown men doing a snow dance in 2008. :pac:

And I was in tears that we missed it. We went from 25 Dec 2004 to 10 Jan 2010 without a flake of snow down here, hence the references to the Cork Snow Shield to this day. As it happens we have done pretty well over the last 10 years, there are definitely worse places on the island for snow.

munsterlegend · 06-01-2021 3:07pm

Rebelbrowser wrote: »

And I was in tears that we missed it. We went from 25 Dec 2004 to 10 Jan 2010 without a flake of snow down here, hence the references to the Cork Snow Shield to this day. As it happens we have done pretty well over the last 10 years, there are definitely worse places on the island for snow.

Cork snow shield appears worse than it is as so many of us to give out about the lack of sneachta. Hopefully see a dusting later.

Gaoth Laidir · 06-01-2021 3:14pm

Snow timings, based on the latest airport TAFs (vaild to midday tomorrow), which have just been amended around lunchtime.

Dublin
Light snow (1200-m vis.) from 4 - 8 am
Chance of it continuing to 11 am

Cork
Light snow from 5 am - 12 pm

Belfast Aldergrove
Moderate snow (400-m vis.) from midnight - 6 am

Shannon
Chance of light snow (1400-m vis.) from 1 - 5 am, slight chance from 6 - 11 am.

No TAF for Knock.

Donegal, Sligo (to midnight)
Sleet

Derry Eglington (to 9 pm)
Chance of moderate rain from 8 pm.

nacho libre · 06-01-2021 3:27pm

It's beginning to cloud over now. It's a pity we could not have a freeze before the cloud rolled in.

Nqp15hhu · 06-01-2021 3:28pm

nacho libre wrote: »

It's beginning to cloud over now. It's a pity we could not have a freeze before the cloud rolled in.

Yeah that’s my main concern. It needs to be subzero.

Light Snow - Overnight Wed/Thu 6th/7th January 2021

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