South East & East Anglia Regional Weather Discussion 25/11/13

[Jax]

I was wrong about the cloud, it cleared and sun back out here (still not been out, lazy sod that I am LOL)

[Snowangel-MK]

I was wrong about the cloud, it cleared and sun back out here (still not been out, lazy sod that I am LOL)

Cloudy here now but we had a lovely walk before the sun was totally lost .......next thing is what to have for lunch ..

[Summer of 76]

Still sunny here but for how much longer

[VillagePlank]

 

GEFS going for snow all day Friday (from midnight to midnight) at Heathrow. Certainly going to change for the next run.

 

Yikes - back to watching each and every run, then lampposts .... bring it on!

[Sussex Jules]

gefs_850.gif

 

GEFS going for snow all day Friday (from midnight to midnight) at Heathrow. Certainly going to change for the next run.

 

Yikes - back to watching each and every run, then lampposts .... bring it on!

 

Sparkicle please keep up with your postings. I find your input in these out of the ordinary situations most valuable.

[Captain Shortwave]

CFS time

Merry Christmas 

Breaks down from there

Precipitation - (-1) Some rain/sleet snow Xmas eve/day, drier thereafter (rain on the 29th)

Temperature - (-1) - Very cold start, milder later

[VillagePlank]

GFS 12z does not look like snow

 

Here's the critical charts,

 

 

Basic rules of thumb (for me) are that 850hPa thickness must be < 129dm and the 850hPa-700hPa must be < 154. Early hours Friday morning, these values ares 850-1000tk = 129, 750-850tk = 152. The 850-1000hPa/tk puts this ever so slightly the wrong side of marginal according to rule of thumb and given that SLP is likely to be around 1020hPa it looks like snow is unlikely from this run except maybe East Anglia, Cambridgeshire etc.

 

Even a very subtle shift in model output can turn this - ie air mass shift by 30 or so miles - or even local factors like shower intensity -even a moderate shower would turn to snow - and certainly almost any height would see snow since the forecast for sea level is so close to being a snow forecast.

 

Given GEFS output, I'd say that this GFS run appears to be a bit on the warm side, and would not pay too much attention to it, unless it verfies over the next few runs.

[Reefseeker]

Took the lad out metal detecting on Esher Common as day two of his 'do things from my happy childhood' weekend. I had forgotten what hard work it is, first to convince my son the metal detector is working as we 'don't seem to be finding anything'(!) to the sheer joy of digging up ground when we get a 'hit' and the resultant cuts and blisters; got an old halfpence piece, a twenty pence piece and some indistinct lumps of metal in our haul. 

 

Generally cloudy with a bit of sun, 9 degrees according to car but feeling colder; very lovely in the woods. A couple of pics: 

 

Edited December 1, 2013 by Reefseeker

[SteveCoops]

Dammit just realised for this first winter in my new house, I don't have view of a lamp post from where I'm sitting infront of the PC. Might have to rig up a camera

[VillagePlank]

Another reason to not expect snow is that the 850hPa wet-bulb temperature is > 0degC. This chart is not available for free (at least not that I can find) but you still get a reasonably good approximation from free charts,

 

First you need the temp at 850hPa and the relative humidity at 850hPa

 

 

(Here comes the maths)

 

First you need to calculate the dewpoint: temp - ((100-rh) / 5). In this case it's -6 - ((100-60)/5) = -6 - 8 = -14.

From here you can calculate the wetbulb temperature : temp - (temp - dewpoint) = -6 - (-6 + 14) = -6  + 8 = 2degC.

 

This value needs to be below zero for snow to fall.

Edited December 1, 2013 by Sparkicle

[Jax]

Cloudy here now but we had a lovely walk before the sun was totally lost ...

image.jpg

....next thing is what to have for lunch ..

image.jpg

hummmm children, not too well done though and cheap.

 

in other news tried to start the car this evening and as feared having a week off in the cold and damp has left it pooped

 

trying the ole charge it up trick to see if that helps otherwise I am knackered for the 6am start in the morning as just discovered my cover for breakdowns does not include home, if I just pushed it a mile down the road it woudl be OK (stupid world we live in).

 

weather, dunno its dark out though.

[gottolovethisweather]

My view of the forthcoming week, FWIW, do have a gander.

 

http://forum.netweather.tv/topic/78631-model-output-discussion-30th-november-onwards/?p=2850987

[VillagePlank]

Although, I must add, since I am an expert at potato-reading, that the signs for excessive snow are ominous,

 

 

This fella is already in the pot ready to be served with toad-in-the-hole, tonight. Once he's been consumed then inspiration will surely follow.

Edited December 1, 2013 by Sparkicle

[chilly milly]

Afternoon all.  I'm stuffed from the first Christmas dinner this season that my sister-in-law cooked.  Yum.

 

7.3c here and it was dark and cold for the dog walk.

Edited December 1, 2013 by chilly milly

[Snowangel-MK]

do have a gander.

Very kind of you GTLTW but I'm not keen on Goose plus I'm totally stuffed after eating roast child earlier !

[Jax]

I'm totally stuffed after eating roast child earlier !

Not suprised at that price

[gottolovethisweather]

Very kind of you GTLTW but I'm not keen on Goose plus I'm totally stuffed after eating roast child earlier !

 

No need to duck the issue either.

[yamkin]

Hi SE gang,

 

Hope all are well and weekend has been good.

 

GFS is breaking down the cold feed too quickly by the end of this coming week and is known to want to bring in the Atlantic too quickly. Expect a ridge to the North to form and prolong a colder feed.

 

For starters, snow Thursday pm into Friday

Yamkin says, 'let's get ramping'

 

[Snowangel-MK]

Yamkin ramping and it's only the first day of December ...waiting for the Countryfile forecast now :-)

[Summer of 76]

No need to duck the issue either.

GLTW, you have escaped from the Model thread

[Captain Shortwave]

Back from the model thread, appear to be missing a couple of body parts and my arms are now made of lego 

Here is a ramp, there are better ones in there for John to find

Keep looking out for the Scandi high over future runs as well.

Edited December 1, 2013 by Captain shortwave

[Jax]

waiting for the Countryfile forecast now :-)

unless you live in the far north or on the coast then snow is not likely, cold however does seem certain.

[shotski]

With charts like these a BBQ Winter is on the cards

[Jax]

With charts like these a BBQ Winter is on the cards

hold the salad!

[Tom Montalbano]

Hi SE gang,

 

Hope all are well and weekend has been good.

 

GFS is breaking down the cold feed too quickly by the end of this coming week and is known to want to bring in the Atlantic too quickly. Expect a ridge to the North to form and prolong a colder feed.

 

For starters, snow Thursday pm into Friday

Yamkin says, 'let's get ramping'

 

House Snow Ramp.jpg

Ah caught you Yammers, no entry for the Snow Depth Cup yet? If you enter, no exaggerating either, I come through your area every day, on the way to work! Lol

Tom.