Winter 2012 / 2013 Part 3

[iand61]

I am more of a reader than a poster on threads such as this and have read with interest all of the posts regarding whether February is colder than November, March than October etc.

On the whole, I agree with what has been said re. strength of the sun and length of daylight but my honest feeling is that; given the right conditions. any month from November through to April can deliver the heaviest snow of a particular winter and that doesn't necessarily mean a single snowy spell in an otherwise mild mucky season.

Although in one of the worst parts of the country for severe snowy spells (North West England) I do have the advantage of altitude and this has probably helped in seeing lying snow in various years from mid October (1983) i believe through to late April (1981)

Even the winter of 1978/79, the only one of the 20th century big three which I was able to witness did not get going until New Year and was at it's most severe in these parts from early February until mid March, something which I believe was the case throughout much of the country.

The April 1981 fall was one of the heaviest I've ever witnessed and tales i've heard from parents and grandparents mention severe conditions and having to dig themselves of of front doors in March.

Obviously this is not the historical thread and apologies for going on like it is but the point I am making is that we can't really say when snow will fall; yes it should be more likely in January than the other winter months but, as the last few winters have shown, mother nature does not follow given patterns.

Now back to lurking again.

[Aaron]

Normally you'd be right, but that's exactly what happened this year (27C in Minneapolis). Not only that, but some parts of Canada recorded temperatures in March which beat the April all-time record high - St. John reached 27C on 21st March, destroying the previous March record (17.5C) and easily beating the April record (22.8C).

Anyway, to try to get back on topic I agree that the strength of the sun in late winter is vastly overexaggerated. If the air is cold enough, the snow will stick. February on average is considerably more wintry than December.

Where did you get the St John's record? The record for that place is 18.3C in March according to Environment Canada, unless you are referring to Saint John in New Brunswick.

Edited October 6, 2012 by Aaron

[MrSunshine]

All I want to know is what are the realistic chances of a White Christmas for the Northern half of the UK this coming Winter.

[Zakos]

That New scientist article is too simplified and more research is needed.

UV light is absorbed by the stratosphere, but this is responsible for both the destruction and formation of ozone. Any slight net gain in ozone relies heavily on the BDC to transport the excess ozone to the polar stratosphere. It is where the ozone levels are highest that warming of the stratosphere occurs. If the ozone is highest in the tropical stratosphere due to a weak BDC, then the net result is a larger temperature differential between the tropical and polar stratosphere and stronger vortex and vice versa when the BDC is strong.

In solar max years the UV radiation is at its peak and there is a net gain of ozone at the tropical stratosphere - but this will get destroyed by the UV light as well - unless a mechanism is in place to shift the ozone to weaker UV absorbing areas (the polar stratosphere). The mechanism is the BDC but the strength of this is dependent on more than just the level of solar radiation. We know for instance that a strong La Nina will totally disrupt the BDC.

interesting, thanks for clearing that up for me, you certainly know your stuff.

I knew it would be more complicated than the new scientist article would have me have me believe.

[n1russ]

Think Snow

[Aaron]

Snow is the only thing keeping my alive..

[Nimbus Nix]

Piers Corbyn says: "The end of october is probably going to be very cold and snowy" Interesting...!

http://www.itv.com/i.../?Filter=326118

(go to 17 mins in btw [or 24 mins for October forecast])

Edited October 6, 2012 by Tim Banyard

[johnholmes]

Piers Corbyn says: "The end of october is probably going to be very cold and snowy" Interesting...!

http://www.itv.com/i.../?Filter=326118

(go to 17 mins in btw [or 24 mins for October forecast])

no I refuse to be suckered into watching/listening, no doubt a smattering of snow above 2000ft in Scotland and frosts elsewhere will justify him once again.

Who knows it may happen but no one else on 6 October is likely to predict his version.

[bluearmy]

if you can be bothered to sit through the adverts and piers initial 'bigging up of himself' (ugh), its a reasonable discussion to listen to.

[johnholmes]

if you can be bothered to sit through the adverts and piers initial 'bigging up of himself' (ugh), its a reasonable discussion to listen to.

thanks ba-I'll take your word for it but I'm not tempted

[Met4Cast]

no I refuse to be suckered into watching/listening, no doubt a smattering of snow above 2000ft in Scotland and frosts elsewhere will justify him once again.

Who knows it may happen but no one else on 6 October is likely to predict his version.

Agreed. The guys a plank, 85% success rate in being wrong perhaps

[Methuselah]

Piers Corbyn says: "The end of october is probably going to be very cold and snowy" Interesting...!

http://www.itv.com/i.../?Filter=326118

(go to 17 mins in btw [or 24 mins for October forecast])

Ah, Piers Corbyn Says...A game of fun, for all the family!

[Ninman]

The GFS has gone mental! I bet it will be the opposite on the next run

[Met4Cast]

The GFS has gone mental! I bet it will be the opposite on the next run

I wouldn't be surprised if it was still showing come the 12z run, albeit probably watered down. The models have been fairly consistent with predicting blocking becoming established in one form or another

[Summer Sun]

The GFS has gone mental! I bet it will be the opposite on the next run

Deepest FI so no doubt it will be gone soon

[Snowstorm1]

WINTER IS ON ITS WAY i love first GFS charts showing snow shows that it aint that far away...

[Chris K]

There has been a trend on a few runs bringing a northerly of some sorts in deep F.I so who knows.....problem being its T+300hrs or further each time so perhaps unlikely to verify?

Nice eye-candy for October though.

Edited October 6, 2012 by Chris K

[Polar Maritime]

Yes but this is persistently being shown, so a cool down is on the card's for the end of October. Which falls in line with the Met long range update.

Temperatures are likely to be generally close to average, but perhaps falling below normal towards the end of October, with some chilly nights possible and the risk of some wintry showers for upland parts of Scotland.

Updated: 1237 on Sat 6 Oct 2012 http://www.metoffice...st_weather.html

All very seasonal for the time of year, and to be expected.

[Gavin Hannah]

GFS has been hinting at blocking or HP out in FI on some of its runs. Perhaps not as prolonged as a solid winter blocking, but definitely something to keep an eye out for.

Check out the 850 colours!

I do get the feeling that the GFS is picking up on something very wintry this year.

Edited October 6, 2012 by IBringTheHammer

[I remember Atlantic 252]

Yes but this is persistently being shown, so a cool down is on the card's for the end of October. Which falls in line with the Met long range update.

Temperatures are likely to be generally close to average, but perhaps falling below normal towards the end of October, with some chilly nights possible and the risk of some wintry showers for upland parts of Scotland.

Updated: 1237 on Sat 6 Oct 2012 http://www.metoffice...st_weather.html

All very seasonal for the time of year, and to be expected.

Not a chart I want to see, I am only 103m asl, in 0ctober, this far south, I hate the rain

[Polar Maritime]

Not a chart I want to see, I am only 103m asl, in 0ctober, this far south, I hate the rain

Remember these are mid Autumn charts,we are still nearly two months from winter, wait for the cold to build then the snow will come.

[Gavin Hannah]

Remember these are mid Autumn charts,we are still nearly two months from winter, wait for the cold to build then the snow will come.

Indeed, good for the mountain snow though, As well as some decent cold frosty nights.

[Cloud 10]

The GFS 06z was an outlier for later in the run,but still nice to see.

[Polar Maritime]

Indeed, good for the mountain snow though, As well as some decent cold frosty nights.

Yes, that is all im looking for atm. Just been dusting my kit off, hoping for an early season winter climbing.

[Gavin Hannah]

The GFS 06z was an outlier for later in the run,but still nice to see.

Looking at the NH chart above, it does seem that the main vortex is plumped over northern Siberia and Scandinavia meaning we catch the western edge of it, with the Jet going south for a tropical holiday.. Not a bad place to be if it was Mid December.

Will need to keep an eye on the outputs to see if we can get a trend on this feature.

Edited October 6, 2012 by IBringTheHammer