Model output discussion - 20th Feb onwards

[Interitus]

2 minutes ago, Bring Back1962-63 said:

Very briefly, I can see that there is a second station on Svalbard (so I was wrong about that particular point) but the others are on various surrounding islands. I really think that your comments about the 2 week forecast are unfair. The sites that you refer to and the first one that I linked to do not go beyond March 9th or at least I do not see anything there. My second link is for the 2 week forecast with the already falling temperature trend predicted on the first set of charts falling much further between March 10th and March 14th and only going below average by March 13th. I would never wish to mislead anyone - so if you can show a "less cold" forecast chart for the second week, please do so. 

Ok if you want strictly the mainland - Hornsund, Sveagruva, Barentsburg, Isfjord Radio, Pyramiden, Platåberget and Verlegenhuken - data from a selection of these can be seen on Ogimet - http://www.ogimet.com/cgi-bin/gsynop?lang=en&zona=artico&base=bluem&proy=orto&ano=2016&mes=02&day=29&hora=06&vall=All&Send=send

The sites referred to show the Norwegian met figures which was to say not those from your source and if you want to see a less cold forecast, refresh the timeanddate page - the CustomWeather forecast has just updated and is totally different! 

[mushymanrob]

NOAA 500mb anomaly watchers, /newbies.

i, personally, would love the current ecm @ 240 to be correct

 

but the noaa 8-14 day chart

suggests to me this

is what we are likely to get in the timeframe appropriate. the noaa 8-14 day anomaly appears to be moving towards pressure rise to our northwest and lower pressure over central/southern europe much in line with what 'bring back 62-63' described.  but.... i dont think this northeasterly be snowy, just overcast, drab, cold but dry.

Edited February 29, 2016 by mushymanrob

[Tim Bland]

I'm surprised there isn't more excitement on here for what could happen at the end of the week! it is only 4 days away!  I suspect it's because of the amount of let downs so far this winter.  Parameters look much better this time around though. Cold air is already in place as a low swings down from the NW.  IF ECM is correct then it could be a winter wonderland on Friday / Saturday for large parts of England and Wales.

On the previous page Ian F mentions strong support for snow in the SW and wales next weekend.  Is he talking about 5/6th or 12 / 13th?

 

 

ECM

[Guest]

3 hours ago, Interitus said:

Ok if you want strictly the mainland - Hornsund, Sveagruva, Barentsburg, Isfjord Radio, Pyramiden, Platåberget and Verlegenhuken - data from a selection of these can be seen on Ogimet - http://www.ogimet.com/cgi-bin/gsynop?lang=en&zona=artico&base=bluem&proy=orto&ano=2016&mes=02&day=29&hora=06&vall=All&Send=send

The sites referred to show the Norwegian met figures which was to say not those from your source and if you want to see a less cold forecast, refresh the timeanddate page - the CustomWeather forecast has just updated and is totally different! 

Okay -  I definitely owe you an apology. I have just looked at the Ny Alesund 2 week charts which are from the same (rather unreliable) source as those for Longyearbyen and the temperatures do not go nearly so low. In fact they are lower for this week but higher for next week (they are updated automatically hourly and seem to vary a lot more than one would expect!). Here's the link:

http://www.timeanddate.com/weather/norway/ny-alesund/ext

I have not got time right now to go through the data sets for other island stations or for the surrounding mainland coastal sites but will look for an overall trend and produce a more accurate update when I get the chance. Given that the temperatures over the next 10-15 days in this region would appear to be critical in deciding how much cold air the UK can tap into, perhaps another poster can provide some other useful data. I really am incredibly busy this week.

I would also wish to apologise to readers of my original "Svalbard" post and I hope that I have not misled anyone. I have put an amendment at the bottom of the post + a further apology.

Edited February 29, 2016 by Guest
Errors by me

[karlos1983]

1 hour ago, Banbury said:

Worth keeping an eye on

BANK 

if I was to draw a chart after Ian f posted last night about Wales & West Country, that's pretty much how it would have looked. 

[Tim Bland]

Met office still talking about "Rain with hill snow" on Friday despite Ian's comments that there is a very strong signal for snow.  I expect they were sitting on the fence when that forecast was written last night. Hopefully after this mornings ECM & GFS they will start to be a bit more bullish about snow and some early warnings will appear, (as long as the models keep showing it of course).   I just hope lowland southern England can see 1 major snow event and then we can lay to rest this winter and look for spring. 

[weirpig]

even as early as wednesday  snow a possibility over quite a large area  prob sleety but might see some snow grains

[weirpig]

Gfs  from the 0z to the 6z   precipitation gone within the space of 6 hours.

[Polar Maritime]

Plenty of interest this week as a cool/cold unsettled N/W flow for Tue/Wed could bring some snowfall for parts, Towards the end of the week winds turn more Northerly giving some hard overnight frosts under clear sky's, With the risk of snowfall even in the South at low levels at times. A proper wintry week coming up at we enter Spring. As always expect swings re snowfall on in-trim model runs.. 

GFS 0z

 

Edited February 29, 2016 by Polar Maritime

[weathernuts]

59 minutes ago, weirpig said:

Gfs  from the 0z to the 6z   precipitation gone within the space of 6 hours.

Different timescales. 7am to 1pm

[cheshire snow]

Wednesday and Friday looking quite wintry accross England/Wales

On the 06z,really cannot take the snow risk charts seroisly though

As the GFS has a bias to ramp up these charts.

C.S

[weirpig]

5 minutes ago, weathernuts said:

Different timescales. 7am to 1pm

[weirpig]

Some snow starting to show up now for wednesday on the euro 4  scotland  northern england and ni  initially but i would have thought snow moving further snow later on?

[weirpig]

weather warnings out aswell for tonight for parts of the north  mainy over higher ground.

[nick sussex]

Have to hand it to the UKMO because the ECM and more especially the GFS have moved towards its solution over the last few days.

The  ECM later wants to bring the Azores high in from the sw but this looks dubious as the signal should still be for the Euro troughing so any ridge likely to be more to the nw.

I think the UK snowshield might actually get breached this week. Hope I haven't jinxed things now!

[fergieweather]

2 hours ago, Tim Bland said:

On the previous page Ian F mentions strong support for snow in the SW and wales next weekend.  Is he talking about 5/6th or 12 / 13th?

No, to be clear, I said strong ENS support for the *broadscale set-up*. That's quite a different matter to "strong support for snow". What I wrote was that if the 12z yesterday verified 'as is',  it had snow in aforementioned areas. The 00z has a very different areal distribution. And inevitably, that sort of signal will continue to change run to run. Whilst the sub-528DAM, deeply unstable airmass of eg Weds and again later week will quite evidently threaten some areas with heavy, thundery showers and potential snow even to lower elevation in places, the nuance regional detail will remain elusive until short lead time.

[SLEETY]

22 hours ago, Frosty. said:

7 minutes ago, nick sussex said:

Have to hand it to the UKMO because the ECM and more especially the GFS have moved towards its solution over the last few days.

The  ECM later wants to bring the Azores high in from the sw but this looks dubious as the signal should still be for the Euro troughing so any ridge likely to be more to the nw.

I think the UK snowshield might actually get breached this week. Hope I haven't jinxed things now!

owww most probably if things can go wrong with snow in uk,they usually do

 

 

[fergieweather]

The major issues (for those who are keen on snow) forecast-wise are multi-fold this week, hence treating current snow prognosis charts with due caution. Aside from inevitable shower distribution uncertainty (eg Weds), Fri is complex given varied model treatment of shape of the low; exact positioning; and tendency for occlusion debris circulating in flow to periodically raise WBFL, making exact delineation of snow v mixed phase/rain very difficult. Latest UKMO-GM WBFL/PPN phase (below, obviously NOT to be taken literally!) exemplifies how such margins might be fairly narrowly defined on Fri, but a growing threat certainly of snow on northern flank of the system, even to low levels.

In short: a mare. 

[weirpig]

5 minutes ago, fergieweather said:

The major issues (for those who are keen on snow) forecast-wise are multi-fold this week, hence treating current snow prognosis charts with due caution. Aside from inevitable shower distribution uncertainty (eg Weds), Fri is complex given varied model treatment of shape of the low; exact positioning; and tendency for occlusion debris circulating in flow to periodically raise WBFL, making exact delineation of snow v mixed phase/rain very difficult. Latest UKMO-GM WBFL/PPN phase (below, obviously NOT to be taken literally!) exemplifies how such margins might be fairly narrowly defined on Fri, but a growing threat certainly of snow on northern flank of the system, even to low levels.

In short: a mare. 

Excuse me for the ignorance  but i persume the white  marks are the threat of snow?  if so it is fairly widespread.

[SLEETY]

no snow then in south looking at that just wales and parts of midlands ???

[MP-R]

42 minutes ago, fergieweather said:

No, to be clear, I said strong ENS support for the *broadscale set-up*. That's quite a different matter to "strong support for snow". What I wrote was that if the 12z yesterday verified 'as is',  it had snow in aforementioned areas. The 00z has a very different areal distribution. And inevitably, that sort of signal will continue to change run to run. Whilst the sub-528DAM, deeply unstable airmass of eg Weds and again later week will quite evidently threaten some areas with heavy, thundery showers and potential snow even to lower elevation in places, the nuance regional detail will remain elusive until short lead time.

Interestingly, a few forecasts I've seen for Bristol Airport have the lightning symbol for Wednesday. I guess there's as much chance of thunder as there is snow on relevant days this week.

[winterof79]

2 hours ago, Polar Maritime said:

Plenty of interest this week as a cool/cold unsettled N/W flow for Tue/Wed could bring some snowfall for parts, Towards the end of the week winds turn more Northerly giving some hard overnight frosts under clear sky's, With the risk of snowfall even in the South at low levels at times. A proper wintry week coming up at we enter Spring. As always expect swings re snowfall on in-trim model runs.. 

GFS 0z

 

Having looked at the general output in greater detail, not on my phone as before, i do see a good chance of these charts verifying for once.

Looking like a classic N/Westerly veering as you say.

[Paul_1978]

So an SSW is imminent apparently. Are the models now picking up on this fact, or not yet?

[The Beast From The East]

Any updates on GFS or UKMO ? It's so quiet on here .  ❄❄❄

[Hull snow]

I think the ssw could help a lot of people who crave cold and snow as its not to late for it to still get very cold and snowy let's hope the changes are imminent in the models