Significant Snow risk - Monday 29th/Tuesday 30th

Throw into that the wind forecast and dare one mention the Bl

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word?

I'm backing Con Sensus

a sprinkling that wont last long..

What I'm going to post here may be more helpful to visitors than regulars who will tend to know most of the following.

The rain (initially) is associated with low pressure moving ENE towards the south coast of Ireland today. This low centre will be twinned with a somewhat stronger low in the Biscay region that will move into France late today. Meanwhile, the northern low will track somewhat inland and likely across Wicklow late tonight, into the Irish Sea by mid-day tomorrow and through north Wales and northern England later Tuesday and into Wednesday.

This low is going to become dominant as the French low fills in upon reaching land, and will be surrounded by a deep layer of moisture and temperatures not very much above freezing. This is causing the forecast uncertainty but in similar past situations it has snowed at least down to 100m above sea level and the wind direction by Tuesday will be parallel to the coast so that eastern Ireland won't be getting a long fetch of warmed up low-level air but the cold, moist air crossing narrow channels between Ulster and Scotland and otherwise having its origins over land. This will tend to keep it very close to the freezing point especially if snow develops in places like eastern Ulster and southern Scotland, northern England to chill the flow of air further.

So it is partly a domino effect, as snow falls upstream in this NE to N wind flow, it raises the chances for snow to fall further south along the eastern side of Ireland. Now if you look at western Ireland, the flow would be coming more from a NNW direction and obviously from an Atlantic source, but this air flow is actually colder at higher elevations so it's a case of assessing how much the surface 1,000 metres of the air flow might be modified by crossing the 8-10 C waters of the nearby Atlantic. My thinking is, not very much modification in this instance because of the very cold flow, so we are likely to hear about heavy snow and hail showers in the western counties, heavier where the ground is rising from north to south (as in parts of Mayo for example). I don't know exactly where Nacho Libre lives but from past reports, I am optimistic for him to see some heavy wintry showers. Someone like Deep Easterly who lives closer to Galway (I believe) may see more of a mix of rain, hail and snow because he's on the downsloping side of the terrain from a northerly flow, but when the winds come around more NW'ly as they may on Wednesday then you have different upslope and downslope conditions and this affects who gets the heavier showery potential.

Bottom line is this -- while this snowfall potential could bust and just turn into hill snow, everything seems on the right side of marginal to produce some heavy bursts of snow and this tendency will be spreading at first from north to south and from higher to lower elevations, then it will tend to be more of a day-night question, but I am saying in the boards.ie forecast (fingers crossed tightly here) that 5-10 cms could fall in parts of eastern Ireland on Tuesday and Wednesday. There could be a very heavy fall on the Wicklow and Dublin mountains, 20-30 cms would be quite plausible there.

I rarely venture in here but the forum mods don't seem to be around. Note to various posters in this thread. Cool your heels for a while! You know who you are, give it a rest and put the personal stuff to one side. Thanks

Mods, your call as to whether to take action on any of the posts in this thread that deserve it.

According to metcheck it is snowing heavily here in Galway - not !.

No wonder people don't trust forecasts.

YrNo forecast for Galway has changed a lot with rain extended into tomorrow whereas last night they were showing Tues as dry.

Simples the snow gods are listening to the prayers of people who have just received horrific ESB bills !. We do not want any more snow !

I gathered that by the fact that the rain is moving ssw to nne & the wind is blowing in pretty much the opposite direction.

Loads of rain coming up from the south so shannon radar should go down any minute !

Nah not heavy at the moment but there are heavier bursts in it & the rain to the South is heavier.

13.2mm rain so far , current temp 3.9°C, probably snowing up on the higher Wicklow peaks already.