[Model Output Discussion - What does April have in store?]

Was attempting to read the thread for the first time in two to three days and well, a few assumptions going on as always it seems.

A lot of posts from numerous people in here over recent days claiming bitter cold, or unseasonal warmth, what will occur around the Easter weekend will probably be the atypical Spring season setup if truth be told.

The weather will deliver what it wants to, but rarely do the charts at t+144 hours (akin to t+12,840 minutes or something like it) verify at the SURFACE anyway, so a lesson to be learned there. So, again, if one is confused as I have been, especially considering I haven't seen a long-ranger on the BBC either, I'll go for my assumption above or my best guess below.

Cloudy nearer the East coast, best of the sunshine and warmest out West. Several downpours for central, southern and eastern parts initially early to middle of the upcoming working week then drying up and becoming settled away from the far North in the run up to Easter weekend. Cloud amounts for all, UNPREDICTABLE at this range.

Best Wishes

gottolovethisweather

 

 

 

 

 

[Model Output Discussion - What does April have in store?]

48 minutes ago, Frosty. said:

For sure it's not funny haar haar but I'm not going to fret about it, just wait and sea what happens.

Love it. The humour, that is 

[Cold hunt - models and chat]

34 minutes ago, That ECM said:

Day 8/9 is reliable but 11 isn’t?

For a definition of where FI or the unreliable forecast options begin, one should have a glance at the netweather guides to reading the enembles. For my opinion on this, read below.

 

The reliable is never a static position either, with FI, i.e. the non-reliable for surface observations is said to be starting at around D5 right now, according to some respectable members in here. The reasoning behind this is that suggestions of Shannon Entropy are at play. The best guide is to look at the GEFS or ECM ensembles and see where the most significant divergence of options begins, as it is at that timeframe that the unreliable and FI starts.

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

7 hours ago, kumquat said:

13cm here. some got 20+ in Mendips, out Bath way and Somerset (add in further East overnight and today Wilts, Berks, Hamp.) Glos, Cotswolds, S Wales got into Northern Extent as did Ox) Further in town (Bris) probs a bit less but 10 to 12 cm widely. Cornwall, Devon got high moors action and unexpected sea level snow (include Dorset) - I saw Hayle and Newquay recording heavy snow - Main road over Bodmin got out of hand 100s put up overnight!. It was one of those nights where nowcasting was King and the models were "erratic". And it kept going all day today. Multiple, stalled and fully circulatory mesoscale features breaking away and feeding back into Occlusions and associated Upper Low fronts caused havoc (several times over the period)

You should do news reports on the Beeb with all that detail. I agree with all you say. Off to check my 9 am snow cover.

EDIT: 140mm now so broadly speaking, 5 1/2 inches, lost half an inch since last evening. The slow melt continues once the AT rises high enough.

 

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

10 hours ago, *Stormforce~beka* said:

I tell ya what though guys it has been facinating to watch for sure! So many not due any. And I think all of us saw at least some snow in the end. Albeit a sugar coating here or a dig me out job there. Very rare for everyone to see something. We have been lucky to have it at all even if not the amount some wanted or way too much for those that wanted none. I would love to know the ins and outs in thicko language as to why what happened did - both the stalling - the 2ndry low feature - the tiny amounts for here - the falling but not laying etc etc. Lets hope summer is as exciting in storms! Ah I love weather

Firstly we had the jet diving way south of us. A snow-covered near-continent meant winds from that direction would feed us the right conditions for producing extra quantities of snow. A succession of frontal features was embedded within the surface low, and the initial one took an age to reach all parts, so in effect did stall catching forecasters out. The precipitation was also heavy enough to sustain snow instead of sleet for large areas of the region. All of this should tell us that meteorology is a learning curve every day and the pros are not infallible, it is Mother Nature playing games with us after all. The overnight warnings were correct for my region, as they stated it would last all day Friday in effect, but why they downgraded them to a Yellow warning by morning, I don't know.

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

Garden birds sorted. Snow cleared from feeding surfaces, fed, water topped up, fat blocks and mealworms replenished. B*%$^r that being a bird in this weather. Another good inch has fallen I'd say since my 9 am observation.

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

Still falling lightly as per many others and we have an approximate snow cover of 50mm here in Newbury at 9 am. AP at 984.6mb still plenty low enough for a whole day's worth of intermittent snow around. It will be quite a memorable event to look back on, I reckon. 

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

1 hour ago, gottolovethisweather said:

That Fax Chart as posted by Knocker is a thing of beauty, what a rare opportunity this has turned into for some of us. A good few inches in selected prone spots overnight and into tomorrow, a day of intermittent snow continuing for some parts then as well.

Note the two surface lows and frontal features, one or two of which were unexpected I believe.

Fax Chart post by Knocker

 

 

See my previous in relation to Knocker's Fax chart post previously. The Fax Charts are updated during the actual weather event itself as new information is fed in, hence the extended warnings to late afternoon tomorrow for some. Don't go thinking we're due hours and hours of heavy snow but do be thinking, most of us will wake up to a wintry scene by the morning with some parts getting more than previously anticipated. AT in Newbury now -0.2c DP -2.8c and AP 983mb and slowly falling. 

 

As to who, where, when and how much I still favour the regions mentioned in my post below for the heaviest snowfalls and accumulations.

 

Who will get the highest snow depths?

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

3 minutes ago, alex12 said:

Yep orange warning now gone from Met Office!

Replaced with a yellow one for my neck of the woods and snow symbols and a new weather warning of snow and ice right through to 5 pm tomorrow afternoon. Plenty more surprises to come methinks, with more precipitation heading into Cornwall overnight as well.

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

That Fax Chart as posted by Knocker is a thing of beauty, what a rare opportunity this has turned into for some of us. A good few inches in selected prone spots overnight and into tomorrow, a day of intermittent snow continuing for some parts then as well.

Note the two surface lows and frontal features, one or two of which were unexpected I believe.

Fax Chart post by Knocker

 

 

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

6 minutes ago, Bring Back1962-63 said:

I agree with you 100% as usual James  

Some on here are looking at misleading information and making erroneous comments - I understand the excitement/disappointment etc.  The snow area has actually been expanding (not contracting). Most models did NOT forecast the the breakaway LP forming on the upper occlusion ahead of the main LP which now may be spawning another break away feature or is becoming even more east/west and pivoting/elongating. This is a highly complex set up and is continuously evolving.  

On the current NetWx I should be under rain but here in Exmouth, I'm less than a mile inland and at a modest 65m and it has been snowing for several hours now, often quite heavily.  It has now settled on all surfaces - about 1 cm on the road and pavements and well over 2 cm on the cars and grass. It looks set to continue on and off for much of the next 12 hours.

Most models did NOT forecast the the breakaway LP forming on the upper occlusion ahead of the main LP which now may be spawning another break away feature or is becoming even more east/west and pivoting/elongating. This is a highly complex set up and is continuously evolving.  

Live Pressure (UK chart is GMT and NW France chart is GMT + 1 hour):

Watch that LP as it should move eastwards or north eastwards. It sucks down the cold air from the north and maintains the precipitation. I believe that another small centre may formv (or is already forming off) Land's End - the main centre is still over 200 miles to the west of Land's End.  The surface occlusion is likely to pulse north and south several times along these mini features.  The upper occlusion is roughly along the line of heaviest snow (red/deep pink on the radar) east to west from mid Surrey westwards to north east Devon.  The clearance in the west has stalled as part of the snow area returns south westwards.  It is uncertain how much northward impetus there will be from the current occlusion, the breakaway feature, any new feature developing or even the main LP but a fair amount of lighter snow has already pushed into the south west Midlands and south east Wales. 

The winds are increasingly backing towards the east north east and the few remaining less cold areas like the IOW will see their temps falling quite soon and join in the fun quite soon (IMO).

David  

 

12

You, sir, are a star! Love your input to this thread. Although, many are disappointed thus far including me in Newbury, the wait will shortly be over. 

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

1 minute ago, Isleofwightsnowgal74 said:

Temp dropping rapidly here 1.6 now and dew point 0.1 what will it take to turn this rain to snow?!!!

Another five minutes at most if your readings are accurate.

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

Just started, oh so light, but thankfully no wet stuff mixed in here. AT 0.7c, DP -2.0c and AP 984.4mb falling slowly. All of this is heading the right way but where will the precipitation band end up? Quite a widespread event for the South for once which is good to see.

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

1 minute ago, rh205 said:

Sleet here in the south of Gosport. More snow than rain though. Snow melting on impact. Large flakes of Snow. Temp 2.4C down -0.9 on last 30mins and down -1.6c on last hour. DP 0.5C decreased by -0.7 in last hour. So we're heading in the right direction. Snow not due until later according to UKMO.

Check the UKMO radar as per my posted image above.

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

2 minutes ago, Frosty hollows said:

Grrrrrr.M4 is killing it! I

I think you're slightly ahead of yourself. The snow will fall quite heavily around Benson, assuming it reaches there and my part of the world in the next couple of hours.

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

Over the next hour or so it will snow readily in most parts I would say judging by this, it is pepping up. I expect larger falls (say 3-4 inches plus) likely over the Mendips, Cotswold and North and South Downs tonight upcoming. It is very slow moving which is good news as far as those wanting some snow cover are concerned.

 

 

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

4 minutes ago, MP-R said:

Indeed. No snow is better than bad snow...

As long as AJ and the rest of us all get our beer and kebabs all will be well in good ole Blighty. I just feel sorry for the farmers trying to farm kebabs in these inclement conditions, a hard packed cover of six inches of snow does them no good at all.

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

1 minute ago, beerandkebab said:

Bugger, snow might even struggle to make it up here....elevation is seemingly the only thing going for me on the edge of the marlborough downs 

Just like Brexit, it is still coming, and even a Corbyn government cannot stop either from happening.

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

4 minutes ago, jethro said:

What does that mean in terms of weather expected, good or bad thing?

I think it means a pepping up of the precipitation and more likelihood of a more prolonged spell. But I'm sure Karlos will clarify that?

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

7 minutes ago, jtay said:

Does @khodds going out on the smash count as non-essential?

Hopefully not a splash then or a lot of us will be slashing ...... over lashings of splashy stuff, here's to a snowbound lock-in at the local or knowing our luck, a post-Brexit ports, shops and government lockdown.

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

2 minutes ago, khodds said:

I need people’s thoughts on how much snow I’m likely to get in Wells - Somerset please? 

That question brings about a proverbial minefield. I would genuinely advise against non-essential travel tomorrow either way.

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

My Air Pressure reading is quite decent too, 989.2mb and falling slowly. Plenty of factors which are encouraging for a proper event now I reckon. Will not start until past 6 pm IMBY but the sky looks such a snow-filled one, and the garden birds are feeding avidly as well.

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

15 minutes ago, Singularity said:

Spotted a drop in dew points in the past hour back down to zero over the Channel and along the South Coast.

That'll be the low-level cold, dry air from the snow-laden N. France lending us a hand. In fact that downward forcing on the dew points could, alongside evaporative cooling, be a critical factor for the far south that keeps conditions the right side of marginal. Perhaps this is what's given the Met Office cause to depict snow even further south than the model consensus.

I think as always in situations like these they'll be reliant on field observations, i.e. our forum posts, for example. Today feels like a quickly changing and still developing event and one which could yet yield much more snow than initially anticipated. Maybe several inches will fall on a local level now I reckon. The latter is more of a hunch than anything else, but what you're stating adds to that outside possibility. I sincerely hope the rain/sleet element is negligible, so most get to join in, in fun.

[Cold hunt - models and chat]

2 minutes ago, Steve Murr said:

Superb 06z ICON

Bang on where FI begins, will it be a case of westerlies or easterlies by the end of next week? We'll find out in a few runs time I guess.

[Cold hunt - models and chat]

3 minutes ago, fromey said:

I keep hearing Sunday being mentioned, can you put any more meat on the bones so to speak?

Only going on what I heard on TV, a front is invading us from the west I believe, aka the start of the currently forecast milder/near average blip. Think rain, sleet and snow mix as per today and tomorrow.