Cold Spell Discussion (19/12/09) (Band of Sleet to Snow to push south)

munsterlegend

munsterlegend wrote: »

whats your view on the shower front activity behind with the cold air? will it be a northern event only?

It won't be a south eastern event.
It will definitely be a westward facing western event and a somewhat northern event including west munster.
Next in line are the midlands and north leinster

p.s air temp has dropped to 3.4c here but the dp is 1.5c

That gives an initial snow line of 800ft in my reckoning.
Maybe 600ft if surrounded by much higher hills and inland.
That snow line will be dropping rapidly as the cold front passes.

munsterlegend

What are met eireann up to?! covering every angle for munster!

National Forecast:

Tonight

Very cold tonight with a severe frost. Occasional hail and snow showers also, chiefly in Connaught, Ulster and west Munster with some accumulations of snow likely. Minimum temperatures of 0 to -4 degrees leading to icy stretches.

and Regional Forecast:

Munster
19 December 2009- updated at 13:00
Today

Mainly dry. Very cold. High of 5 degrees.

Tonight

Rain and sleet clearing. Mainly dry later. Severe frost. Low of -2 to -4 degrees.

Tomorrow

Windy and very cold. Scattered hail and snow showers. High of 4 degrees.

maquiladora

Were living in the wrong place...:rolleyes:

I'm rather superstitious of snow and bitter cold in the NE USA as I've always found that when they have it we don't.

squonk

Radar showing rain in NI now. Here my temp is 4.1 with a DP of 2 so I'm not expecting a lot really!

lucernarian

That front will have travelled a long distance, so it's difficult for me to tell how far any organised precipitation will travel.

I think you'll be lucky to see anything beyond the odd snow shower, unless the main LP system driving this whole setup moves closer to Scotland than predicted.

munsterlegend

To_be_confirmed wrote: »

That front will have travelled a long distance, so it's difficult for me to tell how far any organised precipitation will travel.

I think you'll be lucky to see anything beyond the odd snow shower, unless the main LP system driving this whole setup moves closer to Scotland than predicted.

just looking at the satellite picture there seems to be a lot of shower activity behind.

maquiladora

http://news.bbc.co.uk/weather/forecast/10209

Keeps the front as rain all the way followed by snow showers Sunday, getting fairly far inland as the day goes on but well scattered.

munsterlegend

maquiladora wrote: »

http://news.bbc.co.uk/weather/forecast/10209

Keeps the front as rain all the way followed by snow showers Sunday, getting fairly far inland as the day goes on but well scattered.

and they are usually right!

maquiladora

munsterlegend wrote: »

and they are usually right!

Yeah, starting to the think the GFS went on the christmas sherry a bit early showing widespread snow tonight. I hope I'm wrong though...

munsterlegend

maquiladora wrote: »

Yeah, starting to the think the GFS went on the christmas sherry a bit early showing widespread snow tonight. I hope I'm wrong though...

i'm going away for a while!! its getting more and more of a downgrade as the afternoon goes on. am hoping against hope something unforeseen may develop.

munsterlegend

munsterlegend wrote: »

and they are usually right!

The version showing on the bbc news 24 forecasts has back edge snow in that line of rain.
It's more up to date than the website ie it has dynamic frequent human forecaster input.
I'd be surprised if they look at their BBC web forecasts more than twice in the day.

Deleted User

Deleted User wrote: »

I'm rather superstitious of snow and bitter cold in the NE USA as I've always found that when they have it we don't.

possibly related to the North Atlantic Oscillation? Doesnt that mean the southern states north and west of Florida should get LOTS of snow? Also it ties in with a less cold stratosphere north of Europe. Doesnt mean the North East US/Canada cant get snow though!

maquiladora

maquiladora wrote: »

Yeah, starting to the think the GFS went on the christmas sherry a bit early showing widespread snow tonight. I hope I'm wrong though...

The GFS can be quite accurate sub 24hrs especially with precip.
It's after that when the ECM is the better one I think and the ukmo.

Deep Easterly

As an aside, yesterday (the 18th December 09) was the third coldest day in inland Ireland (so far) in 2009. This goes on the daily mean temperature as per the Met Eireann daily data page.

Top 3 coldest 24hrs periods so far in 2009: (0000hrs to 0000hrs)

1: 7th January 09
2: 6th January 09
3: 18th December 09.

Temperature at Gurteen fell down to -5.6c yesterday morning, followed closely by Shannon Airport at -4.2c.

ninebeanrows

Reports from Scotland would seem to back-up my previous opinion of a lashing rain to heavy snow event.

Probably won't amount to much but we just gotta hope for a really intense band of precip.

WolfeIRE

It is forming into a more organised band as each 15-30 mins passes on the radar.

mad DIY

The current Met Eireann outlook mentions heavy wintry showers of hail sleet and snow for Monday, Tuesday and Wednesday, but doesn't qualify them a being mainly for the north or west, so cause for optimism for all of us in the east ?

WolfeIRE

mad DIY wrote: »

The current Met Eireann outlook mentions heavy wintry showers of hail sleet and snow for Monday, Tuesday and Wednesday, but doesn't qualify them a being mainly for the north or west, so cause for optimism for all of us in the east ?

monday night onwards is very unclear.

would say this is fairly accurate for intervening period:

The showers will be most frequent in the southwest, west and north with some accumulations of snow occurring; scattered snow showers will affect the midlands; parts of the south and southeast will be mainly dry with just isolated showers getting through

arctictree

Temp here currently 2.3c, from a high of 2.9c earlier. We could have a sleet event here. I have noticed that the met.ie radar does not show precip in the North very well, probably out of range.

maquiladora

Reports from Edinburgh and Glasgow saying rain turned to heavy snow in about 2 minutes.

A Dub in Glasgo

I can verify that, heavy rain then heavy snow in a blink - sticking now and I assume the temperature will be dropping as well, it was very cold last night here. My temperature thingy out the back garden got down to -6.5c at 05:30

owenc

maquiladora wrote: »

Reports from Edinburgh and Glasgow saying rain turned to heavy snow in about 2 minutes.

well some snow event here has rained and rained for two hours and rose the temperature to 4c:mad:

mad DIY

Looking at the rain today thing, nothing is showing up west of Sligo, so to me looks like its not going to be an event for anywhere west of there. The front is moving in a south easterly direction so if (and its a massive if by all accounts now) all that rain turns to snow as it moves south, could it be a (relatively) big snow event for the east and south east ?

maquiladora

mad DIY wrote: »

Looking at the rain today thing, nothing is showing up west of Sligo, so to me looks like its not going to be an event for anywhere west of there. The front is moving in a south easterly direction so if (and its a massive if by all accounts now) all that rain turns to snow as it moves south, could it be a (relatively) big snow event for the east and south east ?

Thats just because of the limitations of radar. If you look at the satellite you can see the full sweep of the front better : http://www.sat24.com/Region.aspx?country=gb&sat=ir&type=loop

WolfeIRE

The front does extend west of sligo. Radar is not picking it up. Two pages back you will see a satellite image of the front moving down and you can see that it extends far beyond what is being shown by the met office and ME radars.

You are right though, it appears to be moving south east. This NW wind will leave the west open to showers (you can see them bubbling up already)

maquiladora

Thundersnow reported in East Lothian. :pac:

Thats one thing I've never experienced yet.

mad DIY

maquiladora wrote: »

Thats just because of the limitations of radar. If you look at the satellite you can see the full sweep of the front better : http://www.sat24.com/Region.aspx?country=gb&sat=ir&type=loop

Thanks. I stand corrected. There appears to be a little notch in the approaching front which is probably why nothing showing on raintoday in Mayo yet. Apologies to anyone in the West:o

maquiladora

Sleet/snow reported in Antrim.

WolfeIRE

maquiladora wrote: »

Sleet/snow reported in Antrim.

where you getting these reports Maq?

btw, temp has dropped from 6.5c to 5c since 2pm here.