South West England Cold Spell Discussion

[Methuselah]

Here goes:

[Dartmoor_Matt]

Don't give up mate, if you wake up in the morning & there is no snow, then we have a chance from beffy showers blowing in from the North West tomorrow.

Then if you don't get any snow from that, then yes give up until the new year.

I did just take a peek at the Met Office website which does a Dartmoor specific forecast and it did go for wintry showers becoming frequent tomorrow afternoon, at least thats how it read as it was updated after 3pm this afternoon.

Having said that, I didn't really expect anything from it, we could of done with a low coming in from the SW yesterday... that would of been fun.

[kaz]

yep with the cloud cover temps on the rise, and its RAINING bah humbug..

kaz

[SteveB]

I am sat on the coast & the temp is currently 3.0c, it ain't going to snow with temps that high. Still hoping that it will turn to snow later after the initial rain.

[MP-R]

Jeez, are Arctic fronts always this useless?!

Perhaps our attention should turn to the huge rash of decently-sized showers behind the front.

[Nights King]

Even if people get rain initialy there is a good chance of a dusting as it clears.

3c is quite high though. you will have to take a trip up here tomoro that is asuming we get some?

Going to sneak round the welsh thread and see whats occuring... not much really just talk of deep valleys and subscription charges or sumin lol

-0.9c gulp getting higher

[rowieboyz]

Not looking good guys, even at my altitude I am struggling to stay below 0 C. - 0.5 C at the moment up from -1.5 bout an hour ago.

Looking to the shower activity tomorrow afternoon now.

Jase

[SteveB]

Jeez, are Arctic fronts always this useless?!

Perhaps our attention should turn to the huge rash of decently-sized showers behind the front.

My attention is turning to the showers behind this front. If I get anything from the front then great, but our real chance is from the showers coming in behind.

It would be good though if we could get a covering of 1-2cm's from the front, then further coverings from the showers.

[dogs32]

yes its best to hope for the showers....

Bolton as rain and parts of Yorkshire have blizzard's condition's.

North Staford as sleet so it's a real pick and mix...

If your lucky it could be very heavy and cover your area quickly.

Maybe it will be more snow as it moves more South but I doubt it.

But I think the chance's are at present few and far between from reading many areas in the thread's.

Never liked Northern snow fronts anyway <_<

Roll on the Snow shower's tomorrow

[Ian Fergusson]

And..... deep breaths.

There's still potential - for some, at least.

I wouldn't wholly write-off the snow likelihood for some parts of the SW but clearly, it's an elastic bit of terminology - in an easterly sense - as to where the SW actually begins / ends, versus those who should perhaps switch to the central / southern England thread!

In the broadest sense, at low levels - away from the west coast - the ppn will readily fall as snow. However..... in the rather narrow predicted lobe of the 'warm sector', it will be largely or wholly rain / sleet. Here, the WBFL will be ca. 400-700m.

Conversely, head somewhat eastwards and northwards, and you will find the WBFL at around 200m-ish in some more active frontal activity (very low point probability of lightning further east, too). Add some intensity to the precipitation and you'll likely find snow falling to low levels - especially (and if) the forcing plays a geographic trump card... note we continue to cater for around a 50NM error margin for snow / sleet / rain discrimination and to put this in perspective: drive from the M5/M4 interchange at Bristol to the M4/M25 junction, and you'll discover it's almost exactly 100 (statute) miles.

So, some snow into parts of Glos, Wilts, perhaps Bath and Bristol; eastern and upland areas of Somerset? Sure, the chance is there, but if so, it's likely to be a (short-duration) event at around midnight into the early hours, based on present modelling. In other words: most folk will be fast asleep (apart from some of you.... and me, into work far, far too early tomorrow).

For Cornwall and Devon, the prospect of solely rain is heightened, but again, some wintry stuff on the highest ground seems likely.

It's perhaps understandable to read hyperventilation about the snow / no-snow issue, but irrespective of the ppn type falling across much of our region, it's legacy will be ice.... and that will likely prove the real weather 'problem' for much of the SW's inland districts, come daybreak tomorrow.

As I previously noted, the inland penetration of snow showers tomorrow (especially off the Bristol Channel into Somerset) could become a talking point here.

Meanwhile, please see attached the latest NAE sequence for around midnight. Little great change spatiotemporally in the evolution, but for those of you in the crucial 'flux' area along the M4 between, say, Bristol and Swindon......I stress the discrimination of PPN type remains rather uncertain and so don't be dejected if your 'promised' snow is actually rain or for that mattter..... vice-versa!

[David-kig]

i see there is a freezing rain shower in cornwall anyone wanna confirm??

[Nights King]

Thanks Ian for another update.

Can i ask what you think the prospects for snow are for monday with that channel low that is going to be lurking around?

Meto seem rather vague about it all at the moment.

[kumquat]

Excellent post, Ian. Much appreciated!

[dogs32]

Thanks for the post Ian

My radar pic for my area, as you can see, the Front is now in sight.

Isaac reporting light snow in Brum

[kumquat]

Precipitation intensifying nicely over North Wales. My temp now up to 3.0 C :-( but to be expected as the warm sector kicks in.

[Ian Fergusson]

Thanks for the post Ian

My radar pic for my area, as you can see, the Front is now in sight.

Isaac reporting light snow in Brum

Yup - here's a cleaned image, minus the clutter from the Netweather raw feed - --

[03jtrickey]

And..... deep breaths.

There's still potential - for some, at least.

CUT

Wow - a pro presenter on here - great to have you on board!

What kind of depths are we looking at for Gloucestershire do you think? I was reckoning on about 2cm but I'm not too sure.

Yup - here's a cleaned image, minus the clutter from the Netweather raw feed - --

Awesome! How do you access this stuff? Is it just for pro forecasters?

[David-kig]

theres rain in south west wales first sign of rain in wales now just to warn you all

[Nights King]

strange my temperature is on the fall again now.

-1.4c dew point of -7

the closer that front gets the more nervous i become!

[dogs32]

Im a bit surprised that Front as got into Brum that fast..

At this rate I might have something here by 22.00

[Ian Fergusson]

Thanks Ian for another update.

Can i ask what you think the prospects for snow are for monday with that channel low that is going to be lurking around?

Meto seem rather vague about it all at the moment.

We've just had sight of our latest medium range analysis and it only affects extreme SE quadrant on this run. MO's Global Model doesn't make much of any snow risk for SW (if indeed anything whatsoever) but Tuesday's set-up remains under review albeit again, showing much of southern / SW England dry, cold-ish and fine. There's still a fair spread of solutions between now and Christmas, so no surprise the MO is taking a diligently scientific approach and not going prematurely (and ill-advisedly) beserk, unlike certain newspapers ramping-up the snow threat across southern England based presumably on a glance of previous (often overly cold-bias) GFS output alone. The NAE has grasped the recent snowfall very well indeed, including regionally / sub-regionally, so we'll await the higher-res output with interest - and hopefully due scientific impartiality - as we get past the weekend.

[03jtrickey]

We've just had sight of our latest medium range analysis and it only affects extreme SE quadrant on this run. MO's Global Model doesn't make much of any snow risk for SW (if indeed anything whatsoever) but Tuesday's set-up remains under review albeit again, showing much of southern / SW England dry, cold-ish and fine. There's still a fair spread of solutions between now and Christmas, so no surprise the MO is taking a diligently scientific approach and not going prematurely (and ill-advisedly) beserk, unlike certain newspapers ramping-up the snow threat across southern England based presumably on a glance of previous (often overly cold-bias) GFS output alone. The NAE has grasped the recent snowfall very well indeed, including regionally / sub-regionally, so we'll await the higher-res output with interest - and hopefully due scientific impartiality - as we get past the weekend.

Do you have any hints for the longer-term outlook?

[Ian Fergusson]

Awesome! How do you access this stuff? Is it just for pro forecasters?

It's the MO's bespoke software product (MBS) we use across BBC Weather (and for other media outlets, I believe). It was recently upgraded by the good folks at Exeter to allow scalable mapping to 1km / GoogleEarth local levels with rainfall radar and other parameter overlay. It's especially handy for local radio nowcasting, I find, especially when tied with the Highways Agencies HANET web system of traffic cams for 'ground-truth' realtime obs (where possible). The MO system also has a nifty 5-min scalable update for SFERICS from the ATDNet system, but also allows this to be accessed across much of the globe, which is very handy when providing global Formula One nowcasts on our BBC 606 sports forum & F1 website (there's nothing quite like a thunderstorm in an F1 race....)

[Theresnoway]

strange my temperature is on the fall again now.

-1.4c dew point of -7

the closer that front gets the more nervous i become!

Hi,

Little confused, my latest temp on the METO website says Bournemouth airport is 0.5 degrees.

I would have thought being further east, the temp would have been lower?

Also Kaz in Barnstaple was reporting 3 degrees, are temps varying that much relatively locally?

Any ideas?

Dave

[jethro]

Thanks for that Ian, very informative. From a personal perspective, living in the NE Mendips, I'm keeping my fingers crossed.