[Misc] The Award-winning official "More Snow Tomorrow?" Thread [2024-25 Season]

[Papa Lazarou]

so if you had to put a percentage on the chances of Snow, what would yours be...less than 50%?

It depends if you're asking will be see snow on a specific date or will we see snow in the next 2 weeks?

On any day, it's going to be based upon the model output, and there's little consistency past Saturday.

However, with the current model output, and with the effects of the first pulse of SSW being felt in about 10 days time, I'd say it's 55% likely that we'll see some snow in the next fortnight. Were ECM and UKMO to show more favourable output later today, and the GFS ensembles to show more agreement I'll be happy to raise this.

 

[chucky1973]

It depends if you're asking will be see snow on a specific date or will we see snow in the next 2 weeks?

On any day, it's going to be based upon the model output, and there's little consistency past Saturday.

However, with the current model output, and with the effects of the first pulse of SSW being felt in about 10 days time, I'd say it's 55% likely that we'll see some snow in the next fortnight. Were ECM and UKMO to show more favourable output later today, and the GFS ensembles to show more agreement I'll be happy to raise this.

so without holding you to it and nothing to do with the football on the 26th, what are the chances of it being white (and potential driving problems) on the 26th!! I know it is only guess work, but I have an alternative problem if there is potential for snow on that weekend...

 

[ryans father]

Yes, were the 6Z GFS to be happen as shown, we'd have snow from about Saturday night until april

But, as the Ensemble shows, there a lot of uncertainty... from Saturday onwards.

The ECM & UKMO need to come on board for me to start ramping this period, as they currently don't support such a cold and sustained evolution.

Actually i believe the both the Mogreps model and the ECM 32 day do support increasing cold from a a direction between North and East. It will be interesting to see the latest Met office guidance as i agree things are very uncertain. However most statospheric factors also support cold in the next few weeks. it doesnt mean it will happen of course and the NAO does not appear in our favour, but it is certainly more likely now that at any time this winter.

 

[Da Man Clay]

so without holding you to it and nothing to do with the football on the 26th, what are the chances of it being white (and potential driving problems) on the 26th!! I know it is only guess work, but I have an alternative problem if there is potential for snow on that weekend...

What you're asking for is basically a guess for weather related issues two weeks away. Toss a coin. You'll get just as a reliable answer.

 

[Papa Lazarou]

so without holding you to it and nothing to do with the football on the 26th, what are the chances of it being white (and potential driving problems) on the 26th!! I know it is only guess work, but I have an alternative problem if there is potential for snow on that weekend...

Bearing in mind the 26th is beyond all but the most madcap model output the only information / data that is out there to show trends later in the month is the possible downward propogation of the SSW event. This may generate greater blocking and polar vortex disruption from about 18th Jan. This COULD setup a very cold spell in advance of the 26th.

Another source is the Met Office extended outlook, and that's vague (possibly suggesting a high pressure over us)

UK Outlook for Tuesday 22 Jan 2013 to Tuesday 5 Feb 2013:There is greater than average uncertainty through this period, with no strong signal for any one weather type to dominate. However, on balance colder, drier conditions are more favoured rather than the milder, wetter weather experienced so far this winter.

So, I'd put it only at 20% at present...

 

[chucky1973]

What you're asking for is basically a guess for weather related issues two weeks away. Toss a coin. You'll get just as a reliable answer.

correct, but someone closer to the weather and all those charts will be a better indicator than a toss of the coin!

 

[chucky1973]

Bearing in mind the 26th is beyond all but the most madcap model output the only information / data that is out there to show trends later in the month is the possible downward propogation of the SSW event. This may generate greater blocking and polar vortex disruption from about 18th Jan. This COULD setup a very cold spell in advance of the 26th.

Another source is the Met Office extended outlook, and that's vague (possibly suggesting a high pressure over us)


So, I'd put it only at 20% at present...

thanks! will be in touch in about a week for a further update!!

 

[Papa Lazarou]

Actually i believe the both the Mogreps model and the ECM 32 day do support increasing cold from a a direction between North and East. It will be interesting to see the latest Met office guidance as i agree things are very uncertain. However most statospheric factors also support cold in the next few weeks. it doesnt mean it will happen of course and the NAO does not appear in our favour, but it is certainly more likely now that at any time this winter.

from Ian Fergusson on NetWeather

In summary, UKMO latest goes for brief block; mostly dry & cold next week, followed into 10-15d period by increasing mobility with some rain-snow events from W, with heavy rain becoming more prevalent in SW as Atlantic comes more to the fore. However - and this is CRITICAL point - they stress Shannon entropy has now broken all previous records!! GFS solutions not mentioned in any analysis. Take from that they're leaning to EC but I do stress they acknowledge high state of model volatility, so it's a real poison chalice to be tasked with preparing any outlook summary so far ahead. Thus, major health warning on potential outcomes

Shannon Entropy: Introduction

 

[Papa Lazarou]

Another update from Ian F (which contradicts the previous comment above)

EC suspected as mild outlier. Remember ensemble means will always tend to default to more energetic solution, hence more mobile. Current suspicion is a messy story next week followed by block re-established; critical thereafter is where we sit on side of jet as meridional pattern dominates. Noteworthy how EC clusters for S Midlands remain at 2-4C max from weekend into foreseeable. Battleground events considered highly likely outcome in what will become an awkward forecasting mix next week onwards. ....

And battleground events can deliver huge amounts of snow for those on the right side of the battle-lines.

Ian Fergusson works for the Met Office, so has an inside track on Mogreps etc. It's good to see the pros are flumoxed by this setup as well.

 

[Bevendean Hillbilly]

Shannon's entropy just means levels of uncertainty doesn't it? Is that a meteorological term?

The winter is too f***ing late for me anyway...I needed it to throw it down with snow last time for personal reasons. Snow now will be a distinct balls ache for me so is pretty much nailed on to happen.

 

[Papa Lazarou]

Shannon's entropy just means levels of uncertainty doesn't it? Is that a meteorological term?

I beleive that's all they're saying yes. Never seen it used before though in a met context.

 

[Hillian1]

f*** SAKE.

Is it going to get cold and snow or WHAT?

 

[Muhammad - I’m hard - Bruce Lee]

f*** SAKE.

Is it going to get cold and snow or WHAT?

possibly

 

[Papa Lazarou]

The latest GFS is rolling out and it upgrades the chance of snow this coming weekend. Will need to look at the ensembles, but it's very similar to the last run, but colder Sat - Sun - Mon, with snow.

 

[LamieRobertson]

The award-winning official "More snow tomorrow?" thread [2012-13 season]

Erm is tht snow in SE b4 3 o'clock??

 

[Papa Lazarou]

Well, IF you beleive the GFS (please don't)...

7am Saturday - rain down here, but snow to the north http://91.121.16.5/modeles_gfs/runs/2013010812/90-779.GIF?08-12

By 1pm the colder air is turning rain to snow down into north Sussex http://91.121.16.5/modeles_gfs/runs/2013010812/96-779.GIF?08-12

and by 7pm - it's snow to the coast. http://91.121.16.5/modeles_gfs/runs/2013010812/102-779.GIF?08-12

so, no chart for 3pm... but it's between rain / sleet / snow.

As I said, please take this model with a MASSIVE pinch of salt, at least for now.

Having said that - I've just seen that the UKMO model is now roughly in agreement on the overall pattern, so ..

meteociel.fr - modèle UKMO pour la France, resolution 1.25 degré

 

[LamieRobertson]

The award-winning official "More snow tomorrow?" thread [2012-13 season]

Well, IF you beleive the GFS (please don't)...

7am Saturday - rain down here, but snow to the north http://91.121.16.5/modeles_gfs/runs/2013010812/90-779.GIF?08-12

By 1pm the colder air is turning rain to snow down into north Sussex http://91.121.16.5/modeles_gfs/runs/2013010812/96-779.GIF?08-12

and by 7pm - it's snow to the coast. http://91.121.16.5/modeles_gfs/runs/2013010812/102-779.GIF?08-12

so, no chart for 3pm... but it's between rain / sleet / snow.

As I said, please take this model with a MASSIVE pinch of salt, at least for now.

Having said that - I've just seen that the UKMO model is now roughly in agreement on the overall pattern, so ..

meteociel.fr - modèle UKMO pour la France, resolution 1.25 degré

Lol dont worry as a 'gardener' by trade I take all weather forecasts with a pinch of salt.

I'm more concerned about early February when I am due to hav a break and considering Peak District ..last year I booked to go there and the only decent snow we had was on the very wkd I was due to go and it was cancelled .. Decisions Decisions

 

[Papa Lazarou]

So, for the 2nd time in a row the GFS Op run is a stunning snow-fest. All the way from Saturday night through to the end.

I might need to get this ready:

However, I will wait until I've seen the ensemble & more importantly the ECM output later on before I get too excited.

 

[chucky1973]

Well, IF you beleive the GFS (please don't)...

7am Saturday - rain down here, but snow to the north http://91.121.16.5/modeles_gfs/runs/2013010812/90-779.GIF?08-12

By 1pm the colder air is turning rain to snow down into north Sussex http://91.121.16.5/modeles_gfs/runs/2013010812/96-779.GIF?08-12

and by 7pm - it's snow to the coast. http://91.121.16.5/modeles_gfs/runs/2013010812/102-779.GIF?08-12

so, no chart for 3pm... but it's between rain / sleet / snow.

As I said, please take this model with a MASSIVE pinch of salt, at least for now.

Having said that - I've just seen that the UKMO model is now roughly in agreement on the overall pattern, so ..

meteociel.fr - modèle UKMO pour la France, resolution 1.25 degré

so with these latest models what percent would you say now for snow this weekend? higher than this morning?

 

[ryans father]

so with these latest models what percent would you say now for snow this weekend? higher than this morning?

Yes but still a lot of uncertainty. ECM due out shortly