Snow/Ice warning for Leinster, Donegal, Cavan, Monaghan and Connacht

Meteorite58

Looks like wet snow falling ,possibly large heavy flakes and a sleet mix in places with some sleet and rain to follow, how much snow falls and how much lasts without getting washed out will just have to wait and see.

Danno

nacho libre wrote: »

Was it Gerry giving the forecast:p?

Nope, it was the lovely Elizabeth Coleman. She was looking very well tonight.

redsteveireland

I'll be on to give reports from Galway from 8am, let's see how this turns out.

Cluedo Monopoly

It actually feels warmer in Galway now than it did earlier. Doesn't 'feel' like snow is coming but I will pray to the snow gods before going to bed.

Larbre34

Danno wrote: »

Nope, it was the lovely Elizabeth Coleman. She was looking very well tonight.

How was Gerry looking the last time you saw him?

pauldry

That Elizabeth Coleman gives a good forecast. Very clear and to the point. Its 2.7c here now which is slightly colder than I thought. It will be sleety mix with some snowfall in heavier bursts and any lying snow will be short lived.

JUST.....too marginal

Nqp15hhu

Cluedo Monopoly wrote: »

It actually feels warmer in Galway now than it did earlier. Doesn't 'feel' like snow is coming but I will pray to the snow gods before going to bed.

It’s very cold here. We are down to 1.5c. Dew point is -2c.

Nqp15hhu

pauldry wrote: »

That Elizabeth Coleman gives a good forecast. Very clear and to the point. Its 2.7c here now which is slightly colder than I thought. It will be sleety mix with some snowfall in heavier bursts and any lying snow will be short lived.

JUST.....too marginal

Where is this marginality for though?

Gaoth Laidir

Nqp15hhu wrote: »

For a guide for precipitation type, from the statistics on your weather station.

You need wet bulb temp <0.5c.

My current temp is 2.4c with a dew point of -1.2c which produces a wet bulb of 0.4c.

With this calculator, that provides a snow risk of 50%. (But it would probably still snow because the freezing level is low and there is lots of room for evaporative cooling).

http://www.sciencebits.com/SnowProbCalc?calc=yes

If we raise the humidity to 80%, the dew point is -0.6c and the wet bulb temperature is 0.6c. Snow risk is 30%.

So you need to look at more than the dew point being negative, especially the higher the temperature is.

(The reason why the wet bulb temp is so important is because that is the temperature of the air immediately surrounding the snowflake as it falls to the surface at your elevation)

Yes. These are the highest dewpoints you need at different temperatures to give a wbt of 0.5 C (at sea level).

Temp | Dewpoint | R.H. |
+4.0 °C | -4.9 °C | 50% |
+3.0 °C | -3.1 °C | 62% |
+2.0 °C | -1.6 °C | 76% |
+1.0 °C | -0.2 °C | 91% |

Dazler97

Nqp15hhu wrote: »

For a guide for precipitation type, from the statistics on your weather station.

You need wet bulb temp <0.5c.

My current temp is 2.4c with a dew point of -1.2c which produces a wet bulb of 0.4c.



With this calculator, that provides a snow risk of 50%. (But it would probably still snow because the freezing level is low and there is lots of room for evaporative cooling).

http://www.sciencebits.com/SnowProbCalc?calc=yes

If we raise the humidity to 80%, the dew point is -0.6c and the wet bulb temperature is 0.6c. Snow risk is 30%.

So you need to look at more than the dew point being negative, especially the higher the temperature is.

(The reason why the wet bulb temp is so important is because that is the temperature of the air immediately surrounding the snowflake as it falls to the surface at your elevation)

How much was that, I want to buy one

Gaoth Laidir

Soundings are oh so close tomorrow morning, but altitude will be key. From Leitrim across to Ballyhaise and into Ulster should do ok, with more transient wet snow further south. Heavier precipitation rates than last Sunday but the wbt profile suggest that even with maximum potential evaporative cooling it will still be a marginal call at the lowest levels.

Kermit.de.frog

Nqp15hhu wrote: »

Where is this marginality for though?

Nqp15hhu

Dazler97 wrote: »

How much was that, I want to buy one

There was different options. I purchased the Davis Vantage Pro2 wireless with aspirated fan for £890.

If you want to broadcast your data online you should buy the weatherlink live (wireless system to record and put data online through wifi) bundle, as its £230 on its own.

pauldry

Its marginal South of the line Sligo to Louth. Ulster pretty nailed in for snow. Inland areas South of this. Sligo town is 50 50 at present. Need temperature of 1.6c and we will be ok. Its 2.7c but too breezy for temperature to fall

Dazler97

Nqp15hhu wrote: »

There was different options. I purchased the Davis Vantage Pro2 wireless with aspirated fan for £890.

If you want to broadcast your data online you should buy the weatherlink live (wireless system to record and put data online through wifi) bundle, as its £230 on its own.

Thank you so much, I'm gonna well invest in one

Mount Vesuvius

I think get up in the morning and enjoy what flakes may come before the rain comes.

Mount Vesuvius

Very Marginal, higher ground will be key to get away from the sleet, although colder air further north helps snow to lower levels.Then rain racing up the rear.

Gaoth Laidir

UKMO aviation chart for 06Z has only snow on mountains through an area southwest of a line from Belmullet to Waterford.

Nqp15hhu

If precipitation does reach here, I am expecting light, sleety snow that only sticks on the grass.

There could be a few inches above 250 metres though.

Cluedo Monopoly

I am losing my usual optimism. Just seems too mild in Galway. North Galway might get some decent snow.

Humberto Salazar

Temp actually rising a tad, 3.2 now. DP 0.6. Not enough I'm afraid. I see rain and sleet away from high ground where I am.

Gaoth Laidir

Dublin and Belfast Aldergrove TAFs have only sleet for tomorrow. Knock has a warning for <1 cm of snow.

EIKN AD WRNG 02 VALID 310500/311500 SNOW FBL LESS THAN 1 CM FCST=

redsteveireland

Looks like rain Ted

Nqp15hhu

Soundings look to be productive for light snow here tomorrow night.

If it’s anything like the previous system, it’ll be light flakes that’ll probably fizzle out over time.

Rock Lesnar

Met office charts on the bbc dont look good for snow in meath, the system seems to fizzle out before here, we'll find out in the morning i suppose but im sort of glad in a way after the rain today, we need every dry day we can get

Dazler97

This is a temperature map on rté weather on 22nd December 2010, if only we had those temperatures

gugsy

Temp hovering around 4c all night here in Galway not gonna snow in the morn even tho temps are meant to drop. Just not enough imo. Best of luck further north

pad199207

Dazler97 wrote: »

This is a temperature map on rté weather on 22nd December 2010, if only we had those temperatures

Funny how the graphics looked better 10 years ago than they do now

Rock Lesnar

Temp in meath is currently 2.1 under a clear sky

Danno

Nqp15hhu wrote: »

There was different options. I purchased the Davis Vantage Pro2 wireless with aspirated fan for £890.

If you want to broadcast your data online you should buy the weatherlink live (wireless system to record and put data online through wifi) bundle, as its £230 on its own.

Cumulus is free and will broadcast to UKMO, WUnderground and even your own website if you want to fork out the ~€50 per annum hosting+name package.