Your daily forecasts from Boards.ie weather forum (NO CHAT)

UPDATE _ Saturday, 0130h GMT
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As northeast winds increase overnight to 20-40 mph, heavier sea-effect snow streamers are likely to develop and bring moderate to heavy snow with some thunder and lightning ... this has already begun in parts of Wicklow and south Dublin, but may spread to other regions including Donegal, north and east Ulster, Mayo, some parts of Connacht further inland, and parts of Meath, Louth and Dublin currently dry. These heavier snow streamers may produce squall-like conditions with blowing snow and reduced visibilities and leave local accumulations of 10-20 cms.

This activity may spread further inland towards morning and remnant squalls may reach central and southern counties at times.

Nobody is totally ruled out with the development likely overnight and Saturday ... Wexford could catch the tail end of the Wicklow streamers and get 3-6 cms locally.

Sunday, 28 November, 2010
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TODAY ... very cold with outbreaks of snow developing across eastern counties during the morning, scattered flurries further west and north, some sunny breaks too ... the snow may become heavy at times, and will move across Ireland in a sporadic fashion with some places getting 3-6 cms, others much less. Dial into the "nowcast" snow report threads for further information as the day progresses. Winds will not be too strong today and will be variable in direction, although a northeast trend will develop later. Highs could be as low as -2 C in some parts, and no higher than +2 C for most.

TONIGHT ... very cold with some clear areas dropping to -8 C or lower ... freezing fog and icy roads ... also some continuing snow with more developing off the east coast and moving inland later, while the earlier snow dies out towards the west coast.

MONDAY to THURSDAY ... each day is likely to be similar, cold and windy with local outbreaks of snow, sleet, freezing drizzle and hail ... with some sunshine, more likely in western counties, as winds remain mostly E-NE at about 20-30 mph. Highs each day will be struggling to reach +2 C while morning lows will be in the range of -4 to -8 C and possibly a bit colder in a few spots.

OUTLOOK ... models have different solutions beyond Thursday, but I am leaning towards the continuing cold scenario favoured by the ECM model, with any shift in wind likely to be towards a renewed northerly once this long stretch of E-NE winds fades out. There is a slight chance of a milder turn around next weekend, but we'll have to wait to see if any model consensus develops about that.

Meanwhile, over here it is much milder now, the high on Saturday was 9 C and we had some sunny intervals with a few spits of drizzly rain. May post some updates in a while. Stay safe, the roads are not likely to be too great.

Monday, 29 November, 2010
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TODAY ... very cold with some sunshine for most of the country, although more cloud in the southwest where some snow may continue in parts of west Cork and south Kerry (2-5 cms locally). Later some additional snow may brush parts of the south coast, and there will be a slight risk of streamers developing around Dublin and Wicklow, and these may contain sleet or hail as well as snow. However, for most the day will remain largely dry with highs only -3 to +2 C. Winds ESE 10-20 mph (possibly 30 mph at times in south) adding some chill.

TONIGHT ... clear intervals, very cold with lows -10 to -6 C inland, and -2 C even in some normally mild coastal locations. A few continuing coastal streamers may develop. Freezing fog may be rather widespread after midnight.

TUESDAY ... cloudy with some sunny intervals, stronger winds developing and very cold, highs generally -4 to 0 C, risk of some heavier snow streamers for eastern counties spreading at times well inland, in ENE winds of 20-35 mph. This may be the "peak snow day" in general terms because of the wind, depth of cold air coming in, and so it's possible that some areas will start to see close to storm or blizzard conditions. Amounts will no doubt be highly variable but we may be looking at 5-15 cms in some parts.

TUESDAY NIGHT and WEDNESDAY will continue very cold and if it clears at all on Tuesday night, lows could fall to -11 C over snow fields and -6 C or lower in general. However, it may stay rather cloudy for many areas with continuing snow flurries or squalls. Wednesday will continue very cold with some sunshine developing and fewer snow streamers as winds fall off somewhat to NE 10-25 mph. WEDNESDAY NIGHT may see more bitterly cold lows although cloud is likely to spread in later.

THURSDAY will be partly cloudy and just slightly less cold in light SE winds, with some risk of sleet near the west coast, and snow grains or freezing drizzle further east ... afternoon highs may reach the dizzying heights of 2-4 C and a slight thaw may begin (at low elevations near the coasts).

FRIDAY looks a bit milder again in a weak south to southwest wind flow, allowing a slightly milder air mass to bring in 4-7 C temperatures to west and south coast districts, but it's likely to stay closer to 2-3 C further east, with sleet or drizzle at times, snow on hills, and light rain near the west coast with fog and mist.

WEEKEND is looking somewhat colder again as a northerly flow re-develops and brings temperatures back down to about 2-4 C by day and -4 C inland overnight lows. Flurries of hail, sleet or snow may develop.

I continue to distrust any model indications of large-scale warming and the most likely further outlook is probably going to remain somewhat colder than normal if not quite as cold as this week.

Today (Sunday 28th) here was cloudy and rather mild with a few sunny intervals and highs near 9 or 10 C. The weather pattern across North America is about as bland as I can remember seeing it, at this time of year, which means no big kickers coming along to move the logjam of stagnant weather over the Atlantic.

As I feel a big sleep coming on, I would advise that your best boards option during the day is to check the various weather threads, and see if anyone posts an update here too ... I always appreciate these as I can't always be watching the weather. I have the feeling Tuesday will be the big day now, but would advise people in the south coast and the southwest to keep an eye on the radar in case the offshore cloud masses decide to organize into something for later on, as the flow will be SE today -- what's perhaps lacking is any real organization to this to get something significant happening, after the overnight blob of snow moves on. But something could develop by afternoon or early evening.

ALERT for potential snowstorm and in some cases blizzard conditions developing gradually overnight in counties Meath, Dublin, Wicklow and parts of Wexford, and spreading through Tuesday morning to many other parts of Ireland. Despite the current cold conditions, an even colder wedge of Siberian origin is rapidly moving west today across the Baltic regions and should begin to drop temperatures further across the U.K. and then Ireland overnight and through the day on Tuesday. There will also be a stronger easterly wind gradient developing. These factors combined should create some strong sea-effect snow streamers that will gradually make more substantial progress inland. Another area for possible sea-effect streamers will activate into the south coast, and the east coast activity will expand to cover Ulster. Snowfall amounts of 5 to 30 cms are possible across most of Ireland with the 30 cm amounts more likely to be in higher parts of Dublin and Wicklow and isolated higher districts further inland.

I should emphasize that significant snow may develop this evening and overnight in areas close to Dublin and Wicklow but the more widespread and heaviest snow is more likely to come during the day tomorrow, so expect possibly 2 to 7 cms in some of those areas now to midnight, a further 2 to 7 midnight to 0700h before the main blast develops and extends the snowfall to larger portions of the country.

This activity should begin to fade back to something closer to today's situation on Wednesday but with the additional snow, there may be more issues with blowing snow, icy roads and lower overnight temperatures lasting to Thursday morning.

As always, check in with the active threads on this weather forum to get all the latest reports and insights from the crew here.

Mostly snow, just a slight mixing near sea level as the streamers develop. The thickness levels are dropping to near record low values (the 1000-500 mb differentials) with the 510 dm contour almost touching parts of Ireland by Tuesday morning. This would be consistent with -5 C daytime temperatures and snow even in marginal locations. However, the strong winds interacting with the 12 C sea temps are bound to create some mixing of precip types especially over the water so ... and that reminds me to add the mention of frequent thunder and lightning to this forecast.

Few places will escape this snow, I feel ... but Galway city perhaps 1-3 cms over the next 36h. Once this activity develops it will be strong enough to travel from east coast to west coast before falling apart, and there will be one or two troughs moving west to enhance the snowfall at times.