Prolonged cold spell on the way

Su Campu

Looks like we could be heading into a prolonged pattern shift, with signs of the first split 30hPa vortex developing in the next week. Not a classic, but should lead to increased meridionality, meaning if that northeasterly sets up, it could stay.....then again, a small shift could mean someone else gets it and we're stuck in a milder regime....

One to keep an eye on....

T + 00hrs


T + 240hrs

WolfeIRE

redsunset wrote: »

I can't wait to go home and see these heavenly charts.stupid work gettin in way of me winter watch

should have a word with the boss red. tell them it's a five minute break each time the models runs occur or you are going to take him to court for allowing staff who smoke go on five minute fag breaks every hour.

Redsunset

Cheers Su i had not bothered to check them charts,was only watching main 30mb temps,so it would seem that little spike at beginning of the month is affecting the Polar Vortex,great stuff.

Redsunset

WolfeIRE wrote: »

should have a word with the boss red. tell them it's a five minute break each time the models runs occur or you are going to take him to court for allowing staff who smoke go on five minute fag breaks every hour.

Yeah im gonna have to take up smoking full time.Although give me a pint and i eat them.

Pangea

http://news.sky.com/skynews/Home/video/Weather/Long-range-Weather-Forecast-In-Video/Video/200806315009839?lpos=Weather_3&lid=VIDEO_56784_Long-range+Forecast&videoCategory=Weather

For the Uk she says that snow is in the outlook for the coming week ahead along with a dramatic eyebrow raise

saxo_vtr

Pangea wrote: »

dramatic eyebrow raise

Hahaha! That was hilarious! She is obviously a snow lover too!

Redsunset

Interesting over on NW when they show how we.ve entered phase 4 and it means this chart.showing more or less whats happening.

darkman2

As Winter begins it picks up on where last Winter left off only this time the synoptics are even more impressive. A very early cold period is about to begin. Initially the frost and icy patches will be an issue - but later in the period through next week showers will be turning distinctly wintry with hail and sleet and also snow on high ground. This snow should reach low levels with the North and East most at risk later in the week toward the weekend. This is a very unusual pattern coming mostly from Scandinavia. Expect ground temperatures to drop significantly (this will have an impact further into Winter in terms of potential daytime ice and semi perma frost - both becoming more likely as soil temperatures drop - this will also have a marked effect on sea suface temperatures - expect those to plummet esspecially in the Irish sea where they are currently at the dizzy heights of double figures at times, that's going to change). ATM it's still an evolving situation and changes can't be ruled out but the model concensus is robust - very unusual coldness for the time of year is pretty much certain at this stage after a few days of speculation. If this was the middle of winter we would probrably have another "national emergency". But it's not. Expect winds to veer between Northerly and Easterly for the forseeable future. High ground always favoured for snow as usual. Things are about to get interesting!;)

Su Campu

It's not quite here yet, according to this morning's 06Z synop reports, which give the minimum temperature overnight at Casement as 30.7C!!!!! I think they meant 0.7C!!

Redsunset

Ummmmm interesting model outputs for 0z,roll on the next one.

WolfeIRE

They are interesting but...a word of caution for anyone heading out to build sleighs this morning. There is a strong possibility that the cold spell may be broken by the Friday of next week as the atlantic reestablishes more average temps and brings rain over the country from the SW. Should the models continue to extend this breakdown to a later date with every run then a prolonged cold spell may very well be possible.

I am still not convinced although it is clear that some parts of the eastern half of the country along with ulster will see some of the white stuff next week.

Give it another day or two is what i would say before ordering chains for the car wheels.

ps...why do we have another thread about the same topic? it's all getting a little scattered.

Deep Easterly

WolfeIRE wrote: »

ps...why do we have another thread about the same topic? it's all getting a little scattered.

Was just going to ask the same thing myself, 3 threads open dealing with the same topic.

This morning's ECWMF ensemble mean run keeps it cool and mediocre right up to 240hrs with the airmass continuing to feed in from polar regions:



I hope this won't be a case where the synoptic pattern becomes more interesting than the actual weather itself. Still, will be interesting to see how the whole pattern develops and if it will sustain itself into December.


The deterministic run is far more interesting though at the end:





Not wholly unlike the patten that was to initiate the cold, snowy winter of 1978/79:

maquiladora

Thats a great 0Z GFS run, if that came off you'd expect to see snow at low levels in a few areas alright and no breakdown until deep in FI.

The bad news is the 0Z operational run was well below in the mean from the 27th onwards, at times showing deeper upper cold than any ensemble member.

Tom Cruises Left Nut

I do love a good darkman2 thread !

maquiladora

lol @ 06Z GFS, cold all the way out to 384, no breakdown.

Iancar29

REQUEST: Mod to lock other similar threads, its kinda too much at this stage having all the different threads.

snowjon

The UK Met have just issued an astonishingly cold and wintry outlook - look at this :eek: :

UK Outlook for Wednesday 24 Nov 2010 to Friday 3 Dec 2010:

The period will begin cold, with many central and western areas having some bright or sunny spells. Wintry showers will affect eastern areas, particularly along the coast but these will extend inland at times. The showers will start turning to snow even at lower levels at times. During the first weekend, there is a risk of more widespread sleet and snow for a time, with the possibility of some significant accumulations in places. The cold or very cold conditions are likely to continue into the second week, with widespread overnight frosts and the risk of icy surfaces. There is a chance as we move into December that southern and southwestern parts will become more unsettled as rain, sleet and snow try to push up from the south.

Updated: 1148 on Fri 19 Nov 2010

UK Outlook for Saturday 4 Dec 2010 to Saturday 18 Dec 2010:

The cold or very cold conditions are likely to continue, with precipitation amounts generally close to average, giving the risk of sleet and snow at times in many areas. However, parts of the north and west of the country may be drier than normal. Sunshine amounts are likely to be generally above average, although some southeastern parts may see more in the way of cloud. Temperatures are likely to continue to be below or well below average, with widespread overnight frosts, locally severe. There is a small chance of it turning less cold at times, giving the risk of further rain, sleet and snow in some parts.

Updated: 1151 on Fri 19 Nov 2010

http://www.metoffice.gov...uk_forecast_alltext.html

maquiladora

Latest UKMO outlook for the UK out to Dec 18th says "cold or very cold conditions are likely to continue" and only a "small chance of it turning less cold at times".

12Z UKMO and ECM runs will be very interesting this evening.

nacho libre

saxo_vtr wrote: »

Hahaha! That was hilarious! She is obviously a snow lover too!

Good stuff!

It reminds me of this::D

https://www.youtube.com/watch?v=jGA0JtxIuwQ

It's a shame the BBC are taking him off television.

nacho libre

as we see again the gfs has habit of throwing wobblers, do not read too much into one run showing an atlantic breakdown. it's time to get worried if the gfs outputs are consistently showing a breakdown and the ukmo and ecm suddenly follow suit.
by the way paddy1 how dare use the word mediocre when describing this pattern;)

nacho libre

snowjon wrote: »

The UK Met have just issued an astonishingly cold and wintry outlook - look at this :eek: :

yes. it's amazing to see them commit themselves to such a sustained period of cold weather. they saw this pattern emerging before many others did too
in fact many experts over on netweather were highly skeptical at the time.

oterra

Audreys looking well, and a free weather calendar, cant complain.
Although the forecast was quite short range. Just as well we have the boards!;)

nacho libre

nacho libre wrote: »

Good stuff!

It reminds me of this::D

https://www.youtube.com/watch?v=jGA0JtxIuwQ

It's a shame the BBC are taking him off television.

LOL feckin brilliant

darkman2

Sorry I actually forgot I started a thread on this already!:o


But anyway for those who like cold wintry icy weather we are on the right track. Not going to bother posting the 00z images as they will be redundant shortly but the 12z runs today should be very interesting.

carlmwan

Guys do you think trim (meath) will get any of the white stuff next week

maquiladora

12Z UKMO is better than the 0Z run anyway, so thats positive.

12Z GFS not as good as the 6Z. Very little snowy potential for us until about 180 hours but then the breakdown comes a couple of days later.

Musicman2000

Ah well it was fun while it lasted:)

maquiladora

Musicman2000 wrote: »

Ah well it was fun while it lasted:)

Its not over yet, it hasn't even started. :pac: We are still going to be entering a cold spell next week, what happens beyond that is still up in the air.

Winger_PL

Am I correct by thinking there's a slight chance of a few flakes falling (but not lasting) in Coleraine around Wednesday morning, at least according to GFS?
And no, it has nothing to do with a certain forum member :rolleyes: I'm just trying to check if I'm getting better at understanding the charts.

nacho libre

oh no it's all over one run has changed completely:pac:

even if a breakdown does come, which is likley as time goes on, it could lead to widespread sleet and snow before milder air takes over. so a breakdown doesn't have to be all doom and gloom. in any case judging by the uk met office a breakdown is unlikely to lead to long period of raging zonality. they are obviously confident this pattern will be hard to shift.