South West and Central Southern England Regional Weather Discussion 01/12/2018 Onwards

[Mapantz]

3 minutes ago, knocker said:

The cold front just through here

How squally was it knocker?

[knocker]

1 minute ago, Mapantz said:

How squally was it knocker?

Not very but the rain was certainly quite mod/heavy for a while

[Mapantz]

Pressure is at 1000.00 on my station. I don't think i've seen it that well rounded. 

[Jayfromcardiff]

35 minutes ago, freeze for all said:

Watch the latest video and it mentions the chance of weather warnings for the South on Tuesday but still very uncertain at mo

Ok, I'll take a watch now cheers.

[CheesepuffScott]

8.8°C at the moment, windy and a bit drizzly

[Jayfromcardiff]

What's everyone's thoughts on when warnings might be issued for Tuesday? Surely it'd be tomorrow to give the public notice?

[CheesepuffScott]

Just now, Jayfromcardiff said:

What's everyone's thoughts on when warnings might be issued for Tuesday? Surely it'd be tomorrow to give the public notice?

When we get more clarity on the track of the low, but it's all very tedious

[Jayfromcardiff]

5 minutes ago, CheesepuffScott said:

When we get more clarity on the track of the low, but it's all very tedious

Let's hope they don't leave it until Monday night and then people panic buy.

[AWD]

Certainly the potential for some snowfall on Tuesday eve into Wednesday.

A long way off still yet so best keep our feet on the ground for now but it's nice to see the elusive "channel low":

show up in a rather more sensible timeframe than normal, although this one is more NW/SE for us.  Don't expect nothing like March 2018 though.

 

Edited January 26, 2019 by AWD

[Zephyr]

5 minutes ago, Jayfromcardiff said:

Let's hope they don't leave it until Monday night and then people panic buy.

[Wiltshireweatherwatcher]

8 minutes ago, Jayfromcardiff said:

What's everyone's thoughts on when warnings might be issued for Tuesday? Surely it'd be tomorrow to give the public notice?

IF Exeter have increased confidence after a couple more model runs that the Southern half of the UK will be affected by this upcoming system on Tuesday, I’m sure they will issue a yellow warning tomorrow. Could even possibly issue one tonight if all the forecast models were convincingly singing from the same hymn sheet. But I would expect tomorrow if it looks likely that it’s going to happen.

[Jayfromcardiff]

2 minutes ago, AWD said:

Certainly the potential for some snowfall on Tuesday eve into Wednesday.

A long way off still yet so best keep our feet on the ground for now but it's nice to see the elusive "channel low":

show up in a rather more sensible timeframe than normal.  Don't expect nothing like March 2018 though.

 

Apparently the lows gone further south so it's dropping into France

[lettice]

Its 9.7c here after being 10.4c midday.
Wind has picked up in last few hours, SW 12-18mph with some 28mph gusts.
Its started drizzling here and gone very grey and overcast.

[AWD]

5 minutes ago, Jayfromcardiff said:

Apparently the lows gone further south so it's dropping into France

Wouldn't worry too much yet.  You are not going to get every model run of every model forecast a perfect evolution for everybody's back yard.  Too far south, we remain dry, too far north & we are wet rather than white.  It's a fragile situation that will not become clearer until much much nearer the time, especially when better high res models can show their output on the matter.

Edited January 26, 2019 by AWD
Spelling

[Wiltshireweatherwatcher]

3 minutes ago, Jayfromcardiff said:

Apparently the lows gone further south so it's dropping into France

That’s what I’m picking up too in the Model thread, though some are saying otherwise. As usual, one says one thing, another says another thing which is confusing.

[CheesepuffScott]

Some people are saying further north 

which is it??

[AWD]

The trouble is with the model thread is you are going to get a lot of IMBY posts in there.  A "downgrade" for Leicester, Walsall or Coventry could be an upgrade for Salisbury, Taunton and Bath.

People are going to call "upgrades" & "downgrades" based on their back yard details so best stick to this regional thread rather than the model thread if you want a more realistic and down to earth analysis regarding next weeks shenanigans.

[Wiltshireweatherwatcher]

2 minutes ago, CheesepuffScott said:

Some people are saying further north 

which is it??

Think I’ll wait for Exeter’s verdict. It is somewhat amusing that everyone is suddenly looking at the ICON model for answers. Probably only because the the GFS and UKMO models aren’t out yet.

[AWD]

The 12z ICON for example, doesn't give no way near as much snow as the 06z ICON did but that doesn't mean it's right.  Just a variation on the theme.

This is due to the heavier PPN largely remaining across the channel.  One run on one model showing one possible evolution.

[John88B]

I would say if some runs are showing the low a little further north while others show it a little further south, we remain on course and in the sweet spot. Fingers crossed. 

Edited January 26, 2019 by John88B

[AWD]

We have 3 possible scenarios;

1)  The low runs into NW France along with the PPN and our region remains largely dry and chilly.

2)  The low deepens and runs along the Channel giving a modest snowfall for many areas of Southern England.

3)  The low deepens further and runs further north giving heavier snowfall for areas north of the A303 and a snow to rain event for areas south of the A303.

There are other possible options to like the low travels much further north and gives rain to our region or the low doesn't form at all but I don't see huge support for these evolutions currently.

As things stand, would give the percentage chance of each scenario:

1)  50%

2)  30%

3)  20%

This is before the majority of the 12z output is out.  I will update after the 12z output is out to demonstrate the volatility of this situation.

Edited January 26, 2019 by AWD
Spelling

[MidnightSnow]

9 minutes ago, AWD said:

We have 3 possible scenarios;

1)  The low runs into NW France along with the PPN and our region remains largely dry and chilly.

2)  The low deepens and runs along the Channel giving a modest snowfall for many areas of Southern England.

3)  The low deepens further and runs further north giving heavier snowfall for areas north of the A303 and a snow to rain event for areas south of the A303.

There are other possible options to like the low travels much further north and gives rain to our region or the low doesn't form at all but I don't see huge support for these evolutions currently.

As things stand, would give the percentage chance of each scenario:

1)  50%

2)  30%

3)  20%

This is before the majority of the 12z output is out.  I will update after the 12z output is out to demonstrate the volatility of this situation.

Would scenario 1 help our chances of seeing snow on Thurs/Fri or not necessarily?

[AWD]

Just now, MidnightSnow said:

Would scenario 1 help our chances of seeing snow on Thurs/Fri or not necessarily?

I'm just concentrating on Tues/Weds for now.  That's pushing the forecasting spectrum to it's limits as it is regarding potential snowfall.  Anything past midweek is all goof dala doofnus for now.

[AWD]

12z Arpege supports scenario 2, running across north France;

Edited January 26, 2019 by AWD
Add Geography

[MidnightSnow]

3 minutes ago, AWD said:

I'm just concentrating on Tues/Weds for now.  That's pushing the forecasting spectrum to it's limits as it is regarding potential snowfall.  Anything past midweek is all goof dala doofnus for now.

Same but I was just wondering if it's a win/win scenario. If it all sinks too far south into France, wouldn't that keep us in colder air for fronts pushing in Thursday/Friday. 

Obviously we'd prefer the 3rd option all day long!