What snow event favours Wales and the South West?

[Jackfrost]

I am hoping that we will get something this winter...we had a no snow at all in winter 11/12.....

Wow, not one flake? It was hardly a spectacular winter here, but I didn't realise it was so grim for you lot in the west.

2011-12 was perhaps the most frustrating winter I've experienced, if only for the three times we were on the border of lying snow during the February cold spell. I especially remember one event (February 9th, perhaps?) when we were promised up to 8 inches of snow from a low moving in from the north. What happened? Everything was in place until the last minute, when the system took the snow down the eastern side of the UK and gave us hours of endless sleet.

Now that was frustration, just waiting and hoping that it would turn to snow, not that it did. Following the spectacular end to December 2010, and the not-half-bad November-December cold spell, the winter was an enormous anticlimax.

Edited November 2, 2012 by Jackfrost

[J10]

Wow, not one flake? It was hardly a spectacular winter here, but I didn't realise it was so grim for you lot in the west.

2011-12 was perhaps the most frustrating winter I've experienced, if only for the three times we were on the border of lying snow during the February cold spell. I especially remember one event (February 9th, perhaps?) when we were promised up to 8 inches of snow from a low moving in from the north. What happened? Everything was in place until the last minute, when the system took the snow down the eastern side of the UK and gave us hours of endless sleet.

Now that was frustration, just waiting and hoping that it would turn to snow, not that it did. Following the spectacular end to December 2010, and the not-half-bad November-December cold spell, the winter was an enormous anticlimax.

Last winter there were a few occasions when it snowed, and there were temporary coverings, once in snowed in the afternoon gave a wet covering of 1-2cm but thawed in the evening. I think one of the problems was that the ground was so mild, any snow that fell thawed from underneath.

No real snow coverings here since December 2010.

Edited November 2, 2012 by Jackone

[fUnKy]

if you live in Plymouth it really doesn't matter.

[bradymk]

Where I live in Pembrokeshire, direct northerlies are the best. 17th December 2010 i think it was when nearly everywhere in Wales had heavy snow, it was a NNW/NW wind so we missed nearly all of the snow, whereas Carmarthen eastwards had plenty. Even though it was very cold here December 2010, we had hardly any snow considering what other places had received but what did fall stayed through Christmas. A direct northerly is perfect for here with irish sea convection or a Pembrokeshire Dangler as it is known.

[Duane S.]

Northerlies with embedded troughs will often bring substantial snowfall to parts of the southwest but for the real thing you need a moisture laden low moving up from the SW to come up against frigid air mass and stall. The problem will always be though that by its nature warmer air will be very nearby so you often need a good slice of luck thrown in! But when everything falls right that setup will produce obscene amounts of snow with severe blizzards and drifting.

[Thundery wintry showers]

I was in Exeter during January-June 2009 and there was an unusual snow event on the 2nd/3rd February- on the afternoon of the 2nd snow showers made it all the way across from the North Sea and a stalling low pressure system sent further snow showers in around its circulation despite north-easterly winds. Then on the 3rd, I had heavy sleet, snow and hail showers from a south-westerly (in effect, the continental air accumulated over the English Channel and then got redirected back north-eastwards as lowest pressure relocated to the west). The lying snow melted during that afternoon in Exeter but it remained intact further inland. Then on the 6th we had a "channel low" type of situation. Exeter ended up with two inches of slush which subsequently turned icy, but that was the event that produced 55cm at Okehampton.

Exeter had a further brief snow event on the 4th/5th March 2009, as a showery westerly brought showers of hail and sleet and then a southerly-tracking trough brought organised sleet and snow overnight.

I agree with the general consensus; a stalling frontal system over the SW tends to give the biggest snowfalls but often with lowland snow confined to a narrow belt, while a showery north to north-westerly flow will often bring heavy convective falls but it needs to be a pretty potent blast of arctic air for the snow to settle widely over low-lying parts of Devon and Cornwall. Perhaps the best recent example was the 17th-20th December 2010 when a showery north to north-westerly was then followed by a frontal type snowfall from a southerly tracking low on the 19th/20th.

[Marcus_surfer]

North West winds and battleground events

[Weather-history]

How well did Wales do with this set up?

[Duane S.]

Those living in Wales will generally be looking for a different setup to those in the SW, i.e. like me, living in the far SE corner of the SW quadrant.

The problem down here with Northerlies is that, normally, energy ebbs away as the front crosses southwards down through the country and by the time it reaches here there is all but nothing left! The hills to the North often squeezing the last drops out of it! The good thing is of course there is little or no modification. Occuring in the final 3rd of Feb onwards can help with stronger convection often aiding to pep things up, but then you will often get marginality BECAUSE of the time of year. Often though Arctic air can be very unstable and there are disturbances within the flow that lead to mesoscale features forming. When this happens geography plays a much smaller part, the sweet spots are small but can be virtually anywhere.

Very much IMBY, aside from that ultra-rare low pressure heading out of Bisacy NE and stalling in JUST the right place up against an established continental airmass over the UK, I look for an cold ESE flow brought about from mean low pressure sat over France and a strong Scandi high, bringing in heavy prolonged snow showers. That's been a very rare set up over the past 25 years or so, even through 09/10 and 10/11 winters.

Edited November 3, 2012 by s4lancia

[virtualsphere]

I was in Exeter during January-June 2009 and there was an unusual snow event on the 2nd/3rd February- on the afternoon of the 2nd snow showers made it all the way across from the North Sea and a stalling low pressure system sent further snow showers in around its circulation despite north-easterly winds. Then on the 3rd, I had heavy sleet, snow and hail showers from a south-westerly (in effect, the continental air accumulated over the English Channel and then got redirected back north-eastwards as lowest pressure relocated to the west). The lying snow melted during that afternoon in Exeter but it remained intact further inland. Then on the 6th we had a "channel low" type of situation. Exeter ended up with two inches of slush which subsequently turned icy, but that was the event that produced 55cm at Okehampton.

We also did well on 2nd / 3rd Feb 2009. On 2nd I woke to find a dusting of snow from overnight, and we then had some significant frontal snowfall early on 3rd Feb followed by heavy snow showers. It's quite unusual to get heavy snow showers from an easterly flow but I think we were close enough to the centre of the low pressure on that occasion -

How well did Wales do with this set up?

I don't remember anything significant from this one, looking at the forecast and the set up I think it was more likely to have been cold rain here in SW Wales, and probably any snow would have been in mid and north Wales. I may be wrong though! I remember November and December 1996 feeling cold here as I walked quite a distance to work back then, but not sure we had any major snowfalls.

[I remember Atlantic 252]

We also did well on 2nd / 3rd Feb 2009. On 2nd I woke to find a dusting of snow from overnight, and we then had some significant frontal snowfall early on 3rd Feb followed by heavy snow showers. It's quite unusual to get heavy snow showers from an easterly flow but I think we were close enough to the centre of the low pressure on that occasion -

I don't remember anything significant from this one, looking at the forecast and the set up I think it was more likely to have been cold rain here in SW Wales, and probably any snow would have been in mid and north Wales. I may be wrong though! I remember November and December 1996 feeling cold here as I walked quite a distance to work back then, but not sure we had any major snowfalls.

Probably in SW Wales yeah, but the bbc underestimated the snow that day, imagine over 200m in mid to north/east Wales getting major snow

[damianslaw]

As others have stated, the best set up for snowfall in the SW is the 'channel low' feature bumping into very cold air. Some of the most disruptive snowfalls in british history have occured in the SW thanks to this type of synoptic pattern. Its been a long time since we have seen a classic channel low set up, heights must ridge out of scandi into britain and into the mid atlantic - always a very difficult set up to achieve. Stalling frontal features moving in from the SW taking battle with arctic continental air can deliver very large amounts of snow to SW parts whilst the rest of the country remains dry albeit bitterly cold, in such set ups, the continental air if it is attacking from the NE often wins out forcing the fronts to retreat back southwards - again a very difficult set up to achieve.

Northwesterlies and Northerlies with trough features often bring heavy snow showers to the SW provided uppers are favourable, late Nov 05 was a good example of such a set up.

Long drawn easterlies can provide decent amounts to southern coastal parts of devon and cornwall generally.

In some winters the SW and S Wales can end up having a much snowier winter than the midlands, when blocking takes hold to our NE and E, as the jet is forced on a southerly path clipping SW parts.

The SW naturally tends to do least well in northeasterly set ups, which generally are the most conducive to producing low level snowfall in this country.

Its always interesting seeing the difference between weather conditions in Cornwall and Aberdeenshire - often worlds apart in many respects.

[J10]

How well did Wales do with this set up?

I don't seem to recall that giving us any snow, (probably too close to coast for a frontal event) however there was snow on a Wednesday in Nov 1996, probably 20th November from the resultant NW flow, giving a 1-2 inch covering. (vague recollections)

For some reason I remember the TV show that was on during this event, and it weird how strange connections like this are made.

http://www.ukgameshows.com/ukgs/Wanted

This also shows the value of keeping proper weather (are more reliable) blogs, which I started doing in 05-06.

[Weather-history]

I don't seem to recall that giving us any snow, (probably too close to coast for a frontal event) however there was snow on a Wednesday in Nov 1996, probably 20th November from the resultant NW flow, giving a 1-2 inch covering. (vague recollections)

There were showers for parts of Wales as can be seen by this radar

[johnholmes]

this morning is as good an example of snow as any for parts of the area?

[m0sca]

Indeed, the A37 between Yeovil and Dorchester was closed due to snow!

[Weather-history]

Did Wales get anything from this on the 2nd December 1997? I know we had a little of snow with a cover.