Polar Maritime Air And Low Lying Snow For South

[I remember Atlantic 252]

Polar maritime air/cold zonality, I usually find crap for snow away from the Scotland and Pennine areas, never really that excited about a PM airmass,

but do remember probably my most surprising snow ever, heaviest Ive seen I think on 5th Jan 1998, rain turned to golf ball size flakes, and ended up with 2 inches!

also another very surprising event on a tuesday evening 8th Jan 2008

but generally its just rain and temps around 4C, so maybe i prefer a bartlett, as who wants 4oC and rain

Edited November 26, 2011 by snow? norfolk n chance

[Cheese Rice]

So what is the point of this thread again? lol

Edited November 26, 2011 by Cheese Rice

[Norrance]

Jan 1984 an often quote month for cold zonality / PM air masses. From Trevor Harley's site. Snow lying days.

Kindrogan [Perthshire] - 30

Glasgow / Edinburgh - 20

Manchester - 6

London - 1

Kind of backs up the argument that the further North the better for snow in PM air masses. For further South an Easterly is best.

[Terminal Moraine]

Jan 1984 was an excellent month here too and still stands as the snowiest in my 35 year record with regard to the accumulated depth of snow during the month, just short of 69 cm.

There were also 5 days with thunder, including two with thundersnow, 21 air frosts and 24 mornings with lying snow at 0900.

[Aaron]

Just checked the weather records for Leeds and January 1984 seemed to be a good month, cold, snowy and two days of thunder, not to mention very windy (85mph winds)

Edited November 26, 2011 by Aaron

[Isolated Frost]

Wasn't January 84 the month with the great arctic outbreak stateside?

Pm air locked in and generally a windier flow will give us east of the pennines quite a few showers.

[sundog]

Wasn't January 84 the month with the great arctic outbreak stateside?

I think that was Jan 86 around the time of the shuttle disaster if i remember.

Edited November 26, 2011 by sundog

[I remember Atlantic 252]

Jan 1984 was an excellent month here too and still stands as the snowiest in my 35 year record with regard to the accumulated depth of snow during the month, just short of 69 cm.

There were also 5 days with thunder, including two with thundersnow, 21 air frosts and 24 mornings with lying snow at 0900.

Good elevation for you though, Im way too young to remember Jan 84, but most likely not much snow just over 100m asl

what about 5th Jan 98, how much snow did you get up there?

Edited November 26, 2011 by snow? norfolk n chance

[wolvesfan]

I think that was Jan 86 around the time of the shuttle disaster if i remember.

Hi all,

It was january 1985,the polar outbreak,a SSW ocured when the strat warmed by around 13c,cheers.

[A Winter's Tale]

December 1999 had 7 snowfalls in Glasgow (3rd Highest for December snowfalls in Glasgow in the past 13 years or so). I remember a classic example such as 4th December 1999 which had a brief NWly that brought heavy snow showers in the evening and accumilations of 2-6cm.

I think any snow from Polar Maritime air for the first 10-15 days is likely to be found on the higher ground of the Scottish Highlands with some occasional flakes in lower areas in more rural, Northern parts of Scotland. Personally, I feel that it's quite unlikely for Glasgow to have snow from this event in the start of December let alone Southern England where it would almost be possible. But December has 31 days and probably towards the end the chances of snow in the south will increase.

[summer blizzard]

Just checked the weather records for Leeds and January 1984 seemed to be a good month, cold, snowy and two days of thunder, not to mention very windy (85mph winds)

How many days of lying snow did we get?

[A Winter's Tale]

Just checked the weather records for Leeds and January 1984 seemed to be a good month, cold, snowy and two days of thunder, not to mention very windy (85mph winds)

Where did you get these records from?

[Terminal Moraine]

Good elevation for you though, Im way too young to remember Jan 84, but most likely not much snow just over 100m asl

what about 5th Jan 98, how much snow did you get up there?

Just 5cm on that date and, apart from a trace on the morning of the 21st, it was the only lying snow in the whole month.

[Weather-history]

but do remember probably my most surprising snow ever, heaviest Ive seen I think on 5th Jan 1998, rain turned to golf ball size flakes, and ended up with 2 inches!

That was caused by a low tracking across southern parts, you were to the north of low. Classic situation in these type of flows if you want to see snow. If a low tracks to the south of your location, there is always a chance of a snowfall. It clouded up that day here but we were too far north to get any preciptation.

Other classics include

This one just before Christmas 1993

http://www.wetterzen...00119931221.gif

The Yorkshire folk remember this one from January 1995

http://www.wetterzen...00119950126.gif

The Midlands folk this one from March 1995

http://www.wetterzen...00119950303.gif

Remember this one from late January 1990

http://www.wetterzen...00119900128.gif

This one gave a bit of snow in the far south as it zipped through from early February 1990

http://www.wetterzen...00119900203.gif

Didn't this one gave a little bit of snow to parts of the south? Wasn't it the Bristol area? It was from mid January 2008

http://www.wetterzentrale.de/archive/2008/brack/bracka20080112.gif

Can be little gems these for unexpected snow these.

Edited November 27, 2011 by Mr_Data

[Aaron]

I definitely remember January 1995.. what a fantastic snow event it was. Really deep snow that month and it was only average temperature rise - I'd take it over December 2010 this winter

Edited November 27, 2011 by Aaron

[Weather-history]

A couple more from a long time ago from either end of 1886

This one from early January 1886 gave about a foot of snow in 7 hours in London

http://www.wetterzentrale.de/pics/archive/ra/1886/Rrea00118860107.gif

http://www.ukweatherworld.co.uk/forum/index.php?/topic/61989-the-times-the-great-london-snowstorm-1ft-in-7-hours/

This one gave a wet snow event in the far SE at the end of December 1886

http://www.ukweatherworld.co.uk/forum/index.php?/topic/69785-the-great-boxing-day-night-snowstorm-of-1886/

http://www.wetterzentrale.de/pics/archive/ra/1886/Rrea00118861227.gif

[Thundery wintry showers]

Sometimes I'm left wishing that I'd been around to experience January '84- there must have been some pretty impressive convection about during those polar maritime bursts as well as snowfalls. Other good examples of such months were January 1952 and January 1978. The nearest approach since I started observing the weather was probably the extended spell of "cold zonality" from the 1st to 8th March 1995, though with it being later in the season the sunny intervals in between the showers often lifted daytime temperatures to 4-6C and snow cover tended not to last for long.

I remember references to a snowfall in some southern parts, including the Luton area, on the 22nd January 1988:

http://www.wetterzen...00119880122.gif

In mid January 1978, a burst of polar maritime air was followed by a sluggish low pressure scenario with snowfalls in the south:

http://www.wetterzen...00119780117.gif

And a vigorous snowy depression from January 1952:

http://www.wetterzen...00119520117.gif

I'm often left wishing that we got more intense polar maritime incursions with more frequency, but it's a consequence of our climate, the Gulf Stream/North Atlantic Drift and tendency for a lot of secondary cyclogensis over the Atlantic Ocean. Since Wetterzentrale updated its archive back to the 1870s I looked over a number of winters, on the lookout for examples of "cold zonality" as well as other types of noteworthy weather, and the overwhelming impression was that it was rare even in the late 1800s.

[Bobby]

I think there's a decent chance of some snow on the Brecon Beacons next week. I can see them from here so I'll be looking out. Don't think it'll get much lower though for the South.

[Gord]

All goes to show that weather doesn't fit into neat little boxes. Every weather pattern has its exception.

For us it means a pleasant surprise! Lets hope we get one of them this winter.

Great recollections there...thanks for sharing.

[I remember Atlantic 252]

I did have a wet snow shower on Xmas day 1999, a pm airstream, but still not very optimistic for snow from 1-6th Dec, still feel im too low and too far south

If I lived above 300m esp the further north, I would be very excited

[LomondSnowstorm]

Classic example of a north/south split in a Westerly Pm snowfall event http://www.meteociel.fr/modeles/archives/archives.php?mode=0&month=1&day=11&year=1993&map=0&hour=0 Staggeringly intense chart to look at.

[damianslaw]

From recollection Polar maritime blasts tend to only deliver snowy good to the northern half of the country especially NW scotland - by there nature they are showery affairs and the SE is too sheltered to see much precipitation - even when troughs and fronts move SE they tend to fizzle out over the midlands.

It is very difficult to sustain NW blasts - early March 95 was perhaps the last example of a length northwesterly blast. Here we saw frequent heavy snow showers which were of the very wet snow type quickly melting in the day only to freeze at night.

Dec 99 saw a few northwesterly blasts which delivered much snow to northern hills.

More recently very few examples I have to say, I think we saw one or two during winter 03/04 especially in the run up to christmas.

I do like polar maritime airstreams but they are less reliable for low level snow compared to northerlies, northeasterlies or easterlies, or indeed battleground situations when warm fronts move into cold continental air, or southerly tracking low pressure systems.

[A Winter's Tale]

From recollection Polar maritime blasts tend to only deliver snowy good to the northern half of the country especially NW scotland - by there nature they are showery affairs and the SE is too sheltered to see much precipitation - even when troughs and fronts move SE they tend to fizzle out over the midlands.

It is very difficult to sustain NW blasts - early March 95 was perhaps the last example of a length northwesterly blast. Here we saw frequent heavy snow showers which were of the very wet snow type quickly melting in the day only to freeze at night.

Dec 99 saw a few northwesterly blasts which delivered much snow to northern hills.

More recently very few examples I have to say, I think we saw one or two during winter 03/04 especially in the run up to christmas.

I do like polar maritime airstreams but they are less reliable for low level snow compared to northerlies, northeasterlies or easterlies, or indeed battleground situations when warm fronts move into cold continental air, or southerly tracking low pressure systems.

I got seven snowfalls in December 1999 from topplers which delivered some decent accumilations. In fact it's probably the third snowiest month since I can remember.

December 4th 1999:

I remember this event very well! Some snow showers in the afternoon then a great snowfall in the evening when I was out shopping with my family. It brought accumilations of a few cm and stayed for a while. Perhaps this my first proper memory of a snowfall.

Not sure what you would call this but we did get snow this day (I think a few cm)

Some snow this day.

This day aswell had snow.

[damianslaw]

Dec 99 - I was living in Newcastle at the time and remember a number of days mid month with frequent heavy snow showers which struggled to settle thanks to the marginal uppers. The period 18-21st was cold with long lasting frost. Dec 99 was quite a decent month for snow and cold I'll be happy if Dec 11 turned out similiar and I have to say there are many similiarities with what the synoptics are showing now and how dec 99 started off.

[A Winter's Tale]

Jan 1984 an often quote month for cold zonality / PM air masses. From Trevor Harley's site. Snow lying days.

Kindrogan [Perthshire] - 30

Glasgow / Edinburgh - 20

Manchester - 6

London - 1

Kind of backs up the argument that the further North the better for snow in PM air masses. For further South an Easterly is best.

I can't access any such data on Trevor Harley's Site.