Southwest & Central Southern England Regional Discussion 12th January 2013>

[khodds]

It was sleeting here earlier. Heavy rain too, almost got stuck in a flood that's been there for 3 weeks... Stupid of me to even think of driving through it.

Currently 2.3c here, dew point 3c.

Feeling rather subdued about the whole snow situation at the moment. Looking forward to the cold and ice though. Maybe I'll see some snow in London next weekend. If I can get there!

[Nights King]

We only have access to the 850hpa and thickness' and Dewpoints. Dewpoints are marginal but its more the case that the WBFL increases as the mild sector passes through, turning the PPN to rain away from silly elevations.

What do you class as silly elvations..? I can still see this being a snow turning to rain turning back to snow event? a little anoying because it could wash away the earlier bands snow but it would be better than nothing...

[iowpompeylee]

Snowing in Radstock now with a slushy covering forming on cars and window ledges. Temperature 1.3C and falling.

that means the cold sector is over you and moving south I hope ;-)

[jethro]

Yours isn't showing either so you will need to update it when you can get to a laptop or PC.

For the rest of us, I can see the Sleet and wet Snow line is currently following a line just a few miles due North of the M4 boundary.

Anticipating more reports of sleetiness/snowflakes as the evening progresses.

Back later.

I wouldn't take the radar as gospel, I'm quite a few miles south of the M4 and it's still snowing here.

[iowpompeylee]

To be fair the weathermen got it spot on for us today.they all said heavy rain for us all today but snow on the back edge.so please everyone don't get down heartened today.this situation was forecast days ago.our winter starts later on tonight :-)

[Bobafet]

Hammering down with rain on the south of IOW at the moment, hopefully turn to snow later.

[J10]

We only have access to the 850hpa and thickness' and Dewpoints. Dewpoints are marginal but its more the case that the WBFL increases as the mild sector passes through, turning the PPN to rain away from silly elevations.

This is the WBFL from the GFS, not the NAE, but the point is the same.

As you can see, the WBFL rises in the mild sector, turning PPN to rain;

NAE -

Dew Points are colder on this run.

And the milder sector is further away at least on what I can see.

GFS -

Is a different story, the milder sector is bigger and I could understand less snow on this basis, but not on the NAE.

If it something I haven't access to, fair enough, but otherwise Have I missed something.

[alijoe]

It was sleeting here earlier. Heavy rain too, almost got stuck in a flood that's been there for 3 weeks... Stupid of me to even think of driving through it.

Currently 2.3c here, dew point 3c.

Feeling rather subdued about the whole snow situation at the moment. Looking forward to the cold and ice though. Maybe I'll see some snow in London next weekend. If I can get there!

My sister lives in Glastonbury, I will eagerly watch for your posts this week to check if my nephew (who is as addicted to the snow as myself) will be a happy bunny. Good luck.

[theprophecyman]

Snowing in Radstock now with a slushy covering forming on cars and window ledges. Temperature 1.3C and falling.

Just rain in Frome at the moment, but getting closer I hope, seeing that it's snowing in Radstock, only a few miles up the road.....

[AWD]

What do you class as silly elvations..? I can still see this being a snow turning to rain turning back to snow event? a little anoying because it could wash away the earlier bands snow but it would be better than nothing...

The elevations shown in the WBFL chart in the post above.

You are right though in that for eastern counties of the region, the GFS does indeed show a snow - rain - snow event.

Also, GFS & UKMO still show that occlusion I was on about earlier during the early hours of Tuesday, but I'll await to see the ECM before I comment on that.

NAE -

Dew Points are colder on this run.

And the milder sector is further away at least on what I can see.

GFS -

Is a different story, the milder sector is bigger and I could understand less snow on this basis, but not on the NAE.

If it something I haven't access to, fair enough, but otherwise Have I missed something.

We haven't access to the NAE WBFL chart, but according to a post now from Ian Fergusson now lost in the MOD thread from earlier, it was the WBFL that caused the NAE to show what it as. I will try and find that post.

Here it is, from fergieweather;

"Now serious doubts re scope & evolution of second main snow band later Monday based on NAE extrapolation. Story tomorrow eve into Mon am remains consistent. Atlantic push more pronounced later Monday with early lying snow across west melting; rain atop it, out as far east as around Swindon (at least) with WBFL rising above 400m readily. Watch for further developments later this eve."

Edited January 12, 2013 by AWD

[khodds]

My sister lives in Glastonbury, I will eagerly watch for your posts this week to check if my nephew (who is as addicted to the snow as myself) will be a happy bunny. Good luck.

Cool, I'll be in here daily don't you worry! Good luck too.

[Nights King]

The elevations shown in the WBFL chart in the post above.

You are right though in that for eastern counties of the region, the GFS does indeed show a snow - rain - snow event.

Also, GFS & UKMO still show that occlusion I was on about earlier during the early hours of Tuesday, but I'll await to see the ECM before I comment on that.

Are those WBFL levels to be taken literaly or are they subject to ppn rates and evaporative cooling etc. In other words can other factors over ride these?

Edited January 12, 2013 by mullender83

[AWD]

Are those WBFL levels to be taken literaly or are they subject to ppn rates and evaporative cooling etc. In other words can other factors over ride these?

Not to be taken literally of course, but as a guidance to a necessity for increased elevation to keep snowfall as the mild sector passes through.

Nuance as you describe above will have an affect on the exact level of height needed.

[Beast of Plympton]

3.6c here, getting colder but not cold!

[divadee]

Rain has finally stopped. Temp has noticeably dropped since rain stopped.

[Severe Siberian icy blast]

It's understanable ppl worrying but the thing is I give you one fact. . . The next nae will be different, and the one in the morn again will be different , it seems a bit progressive to me , but we will see later , Iv seen big changes on the nae consistently within the 12hrs time frame I'm afraid so it doesn't cover itself in glory, it was almost like everybody panicked after it came out, including Ian and the met o its understandable I suppose given there status but patience is the key hear I think.

[J10]

The elevations shown in the WBFL chart in the post above.

You are right though in that for eastern counties of the region, the GFS does indeed show a snow - rain - snow event.

Also, GFS & UKMO still show that occlusion I was on about earlier during the early hours of Tuesday, but I'll await to see the ECM before I comment on that.

We haven't access to the NAE WBFL chart, but according to a post now from Ian Fergusson now lost in the MOD thread from earlier, it was the WBFL that caused the NAE to show what it as. I will try and find that post.

Here it is, from fergieweather;

"Now serious doubts re scope & evolution of second main snow band later Monday based on NAE extrapolation. Story tomorrow eve into Mon am remains consistent. Atlantic push more pronounced later Monday with early lying snow across west melting; rain atop it, out as far east as around Swindon (at least) with WBFL rising above 400m readily. Watch for further developments later this eve."

Given that all other factors are better they would this factor be worse, this seems to go against all other factors.

Perhaps the lack of rainfall forecast could have this impact.

[Iceberg]

The wet bulb is the temperature - the dp

Temp of 4. Dp of -2. = wet bulb of 2

Due to this evapo cooling cam bring the wet bulb down as the temp comes down

[iowpompeylee]

The Isle of Wights data. Temp 3.8 and dropping dew point 3.3 windchill 0.6 the wind is now shifting to a easterly :-)

[AWD]

Brilliant long term GEFS suite for the West Country;

A milder blip the 19th - 22nd, but otherwise the MEAN is at -5c all the way through. Operational run was actually a mild run in FI. Amazing.

Plenty of potential there.

[Stoxs]

snow flakes 75% now in any PPn falling some big flakes mixed in there still rain also.

mid hampshire. wish i was 100mtr higher!

[AWD]

Given that all other factors are better they would this factor be worse, this seems to go against all other factors.

Perhaps the lack of rainfall forecast could have this impact.

Could be too. Without the full suite of NAE charts its hard to say.

With lighter PPN then you won't have the effect of evaporative cooling which could sway things.

Try a PM to Ian Fergusson.

Edited January 12, 2013 by AWD

[theprophecyman]

snow flakes 75% now in any PPn falling some big flakes mixed in there still rain also.

mid hampshire. wish i was 100mtr higher!

Wish I was 100 miles East

[wallopweather]

Sleet around Grateley on the drive home from Amesbury about an hour ago. Car temp gauge reading between +2.5 and +1 on the journey

[Bofh]

2.9 degrees in glastonbury and rain. don't have a lampost so will be shining a torch out the window just in case