Snow watch until Sunday 24th (N,W,SW most at risk)

chris2007

Any possible suprises for dublin

highdef

chris2007 wrote: »

Any possible suprises for dublin

Probably not but the area of precipitation moving into the North and Northwest does appear to be both a larger area and more intense that anticipated plus, unless it's arriving early, appears to be separate to the wraparound (I think it's an occlusion) that's due much later in the night.

nacho libre

Cold and wet. When the precipitation is plentiful the parameters are against snowfall. No doubt when the conditions are ripe for snowfall there will be little in the way of precipitation.

igCorcaigh

nacho libre wrote: »

Cold and wet. When the precipitation is plentiful the parameters are against snowfall. No doubt when the conditions are ripe for snowfall there will be little in the way of precipitation.

Cold? Dry.
Water? Rain.

We are an unfortunate nation in a maritime climate. At least when it comes to the white stuff.

Monkeynut

igCorcaigh wrote: »

Cold? Dry.
Water? Rain.

We are an unfortunate nation in a maritime climate. At least when it comes to the white stuff.

Yeah. Its seems the only thing this maritime climate is good for, is the black stuff.

Reversal

Donegal Ken wrote: »

Some snow now been picked up by the radar across southern and Eastern parts of Donegal. Some accumulations in places by dawn.

Just be aware that the radar does not detect snow. All the 'precipitation type' function does is overlay direct model output to the rainfall radar.

Where a model has forecast parameters give a risk of snow and the radar picks up precip in that location, it turns pink. It is no more accurate than the hatched white lines on meteociel.

The UK network has dual polarity which makes it possible to distinguish between the radar returns of snowflakes and raindrops. But this data is not available on the likes of netweather radar. And you have to question how useful that function would be to us. In marginal situations, it will probably always be snow at the altitude the radar is reflecting off the precip.

Rebelbrowser

Reversal wrote: »

Just be aware that the radar does not detect snow. All the 'precipitation type' function does is overlay direct model output to the rainfall radar.

Where a model has forecast parameters give a risk of snow and the radar picks up precip in that location, it turns pink. It is no more accurate than the hatched white lines on meteociel.

The UK network has dual polarity which makes it possible to distinguish between the radar returns of snowflakes and raindrops. But this data is not available on the likes of netweather radar. And you have to question how useful that function would be to us. In marginal situations, it will probably always be snow at the altitude the radar is reflecting off the precip.

No idea if it works, but Netweather have an option called "social" on their radar you can turn on. It allegedly picks up tweets etc about snow in areas and incorporates that into their radar (I think).....

Nqp15hhu

nacho libre wrote: »

Cold and wet. When the precipitation is plentiful the parameters are against snowfall. No doubt when the conditions are ripe for snowfall there will be little in the way of precipitation.

Be patient the cold air is coming tonight

Reversal

Rebelbrowser wrote: »

No idea if it works, but Netweather have an option called "social" on their radar you can turn on. It allegedly picks up tweets etc about snow in areas and incorporates that into their radar (I think).....

It seems to just show colour coded dots on the map where a tweet has #uksnow included, radar than shading the radar return. Handy feature though if used widely. Wonder could we do something similar here, rather than sifting through pages of reports.

Nqp15hhu

Freezing levels tomorrow will be 400-500 metres in Ulster and 300-400 metres on Saturday.

Looks productive for snow to me. It all depends on the duration and frequent (or not) nature of the showers. Hopefully, it’s not loads of hail showers here.

But this airmass is certainly going to be colder than anything we have had recently. It is coming from the Iceland/Greenland region so should have less moderation.

Nqp15hhu

The 516dam line will actually touch the NW of the island for a time on Saturday.

Sounding for Derry on Saturday as an example. Just slightly above freezing but wet bulb is -1c.

The Mig

Kermit.de.frog wrote: »

Be interesting to see video from Edinburgh over the next few hours.

https://twitter.com/edinspotlight/status/1352145706883153927?s=21

sicknotexi

Very little in the way of snow for most of the country in the coming days, unfortunately. Going by the models anyway.

Nqp15hhu

The local microclimate in the hill here pulled through again. Not a drop of snow on the other hills, but snow lying on the road and ground down to 900 feet here. Not sure what causes this microclimate, but it is interesting.





Depending on the frequency of the showers this evening onwards, I don't expect to be able to drive up that road anytime soon.

Slashermcguirk

That is basically slush, no thanks! Hate wet snow that doesn’t stick properly. Scotland on the other hand seems to have got proper snow

Kermit.de.frog wrote: »

That's what we missed by a small margin today. Ah well. Onward

https://www.youtube.com/watch?v=_iu0p5Orjjk

Oneiric 3

Piddling rain here, but at least it's cold.

Nqp15hhu

highdef wrote: »

Decent sized shower passing over Omagh and surrounding areas at the moment and conditions look favourable for snow, going by local reports. Plenty more showers upstream so I reckon there'll be at least a dusting to wake up to in this area.

..... Other areas too, in the North and Northwest. I just highlighted Omagh as an urban and decently populated location. Looks like a fair few places in the North and Northwest will have at least a sugar coating in the morning.

Well they didn’t get any snow as I said. (The hills here actually got most of the snow) This was a warmer trough that came through and only deposited snow above 300 metres.

The low level snow will come tonight if there are any showers.

Nqp15hhu

Reversal wrote: »

Just be aware that the radar does not detect snow. All the 'precipitation type' function does is overlay direct model output to the rainfall radar.

Where a model has forecast parameters give a risk of snow and the radar picks up precip in that location, it turns pink. It is no more accurate than the hatched white lines on meteociel.

The UK network has dual polarity which makes it possible to distinguish between the radar returns of snowflakes and raindrops. But this data is not available on the likes of netweather radar. And you have to question how useful that function would be to us. In marginal situations, it will probably always be snow at the altitude the radar is reflecting off the precip.

The netweather precipitation type radar is very accurate for here.

pauldry

And here.

Hope Saturday morning has snow in Sligo. It might. But it really is white gold. Hard to gather any really though February still trending cold. But in an ever evolving situation it could still turn out to be 14c in February!

Wev even had temperatures as low as minus1 this Winter and it has been raining.

redsteveireland

Oneiric 3 wrote: »

Piddling rain here, but at least it's cold.

Some beautiful skyscapes with heavy showers in the distance towards the Atlantic, none of them making it this far. Not a bad day for a walk.

Meanwhile. https://uk.news.yahoo.com/storm-christoph-thousands-properties-being-223552102.html

Gaoth Laidir

Nqp15hhu wrote: »

It’s all gone quiet in here now that the focus of the snow has shifted north.

UKMO for Derry Eglinton and Aldergrove airporst.

Derrry

Snow
Issued at: Thu 21 Jan 2021 - 11:38 UTC
Valid from: Thu 21 Jan 2021 - 18:00 UTC
Valid to: Fri 22 Jan 2021 - 00:00 UTC
SLIGHT/MODERATE RAIN AND ALSO RAIN AND SNOW SHOWERS ARE LIKELY TO OCCUR AT THE AIRFIELD BUT NO SIGNIFICANT ACCUMULATIONS OF LYING SNOW ARE EXPECTED.

Aldergrove

Snow
Issued at: Thu 21 Jan 2021 - 11:38 UTC
Valid from: Thu 21 Jan 2021 - 18:00 UTC
Valid to: Fri 22 Jan 2021 - 00:00 UTC
SLIGHT/MODERATE RAIN AND ALSO RAIN AND SNOW SHOWERS MAY OCCUR AT THE AIRFIELD BUT NO SIGNIFICANT ACCUMULATIONS OF LYING SNOW ARE EXPECTED.

YanSno

One to watch, two areas of sleet and snow crossing the country on Sunday morning and evening. Amount is very light at the moment and could fizzle out even before reaching the east coast. 1-3cm accumulations in places and a dusting along the east. Subject to change over the next few days of course

Gaoth Laidir

Nqp15hhu wrote: »

It’s all gone quiet in here now that the focus of the snow has shifted north.

The Icelandic aviation chart for 18Z shows rain showers coming down from the north, with only snow showers north of around 60N. Relying on surface cooling well inland for any appreciable snow to fall.

https://en.vedur.is/weather/aviation/sigwx/

Nqp15hhu

Gaoth Laidir wrote: »

The Icelandic aviation chart for 18Z shows rain showers coming down from the north, with only snow showers north of around 60N. Relying on surface cooling well inland for any appreciable snow to fall.

https://en.vedur.is/weather/aviation/sigwx/

With 300 metre freezing levels I’m not quite sure what more you want.

It will snow here. It’s in my forecast.

Slashermcguirk

Wicklow mountains got the most snow of anywhere

Nqp15hhu wrote: »

It’s all gone quiet in here now that the focus of the snow has shifted north.

Gaoth Laidir

Nqp15hhu wrote: »

With 300 metre freezing levels I’m not quite sure what more you want.

It will snow here. It’s in my forecast.

I don't really want anything, to be honest. What I want will not make one bit of difference to what will happen anyway.

Here are the Icelandic Met contact details if you want to update them.

https://en.vedur.is/about-imo/contact/

Nqp15hhu

Gaoth Laidir wrote: »

I don't really want anything, to be honest. What I want will not make one bit of difference to what will happen anyway.

Here are the Icelandic Met contact details if you want to update them.

https://en.vedur.is/about-imo/contact/

You didn’t bother look ahead. The cold air flows in at 11pm-12am from the WNW.

Gaoth Laidir

Nqp15hhu wrote: »

You didn’t bother look ahead. The cold air flows in at 11pm-12am from the WNW.

Hence I clearly stated that the chart was for 18Z.

Wind the neck back in there a bit...

Rodar08

I’ve been reading the weather forum for 12 years and it’s great. I’m really thankful for the lovely banter and posts about what we can expect weather wise .. but you know what really grinds my gears .. is all the stupid bickering between people. Honest to god guys before you press post on your moany comments just remember one thing - nobody cares, gives a SH*T or wants to read your petty nonsense. Then decide just not to comment at all. Private message each other and bicker away to your hearts content.

There is enough negativity and hard times going on in the world without coming on here to read about weather and find people bickering like 8 year olds. Wise up!

Gaoth Laidir

Just to highlight how much colder the GFS is over the other models, here are their respective sig. weather for 9 am tomorrow. The GFS has snow coming right down well into the north, whereas all the others have it 5 degrees further north. The Euro4 is the closest to the GFS but still a mix.