Winter Model Discussion 18Z 12/2/13 onwards.

[snowking]

Not much change from the 12z suite thus far, still not entirely sure why anybody here is giving the GFS op run too much credence beyond day 4 at the moment given that pretty much every run for the last 3-4 days has been a synoptic outlier against even it's own ensemble suite, never mind the ECM EPS.

Overall theme if you were producing an average joe public forecast right now for next would be dry and cold, with overnight frosts and some snow showers into the SE the further on you go. Of course there is potential for this to become a more widespread snowfall event, but up until 144 that is the face value model output.

Interesting to see Ian's post though RE: the modified fields

SK

[Mucka]

GFS still coming around. Some nice eye candy among the ensembles though.

[Met4Cast]

Would such a long fetched easterly also push the Gulf Stream away from are shores ?If so I'm guessing that could also play a part in how cold we will get .

No. The gulf stream is an Atlantic current, it can't be "pushed away"

[Cecil Hogmanay Melchett]

GFS still coming around. Some nice eye candy among the ensembles though.

that is stunning chart,we can dream ..

[Mucka]

that is stunning chart,we can dream ..

Yeah and that is just the appetiser - the main course comes from the N/NE later.

Then we woke up!

[The PIT]

GFS beginning to think about an easterly be a bit later than the others. Time for an ECM wobble now to wind everyone up.

[Methuselah]

Tbh, I'm not going to put too much faith in the Euros just yet...Eight days is a long time in which things can change.

[Mair Snaw]

GFS still coming around. Some nice eye candy among the ensembles though.

If that was to come off i think all us coldies would be like kids in a candy store, what a chart!!.

[Mair Snaw]

GFS beginning to think about an easterly be a bit later than the others. Time for an ECM wobble now to wind everyone up.

Ha Ha Ha, yes it did that in Jan if i remember and this place went into toy n pram meltdown for a few hours until it sorted itself out. as long as the UKMO dont start to wobble as thats been the best model this winter imo.

[Captain Shortwave]

Tbh, I'm not going to put too much faith in the Euros just yet...Eight days is a long time in which things can change.

This is all we need to get to and this is just 4 days off

Only one way from there

[-uksnow-]

Tbh, I'm not going to put too much faith in the Euros just yet...Eight days is a long time in which things can change.

RP - I agree with you to an extent because in reality the latter frames of the ECM etc really are JFF however, this was said last night, how can they be 8 days away when the crucial time period of T96 where agreement diverges between GFS vs ECM/UKMO is the time period were looking at? AND the UKMO only goes out 6 days!

[BM4PM]

No. The gulf stream is an Atlantic current, it can't be "pushed away"

The Gulf Stream can be affected by surface winds as it driven by differences in salinity and surface winds.so if a easterly blows out into the Atlantic it will slow down .

[SnowObsessor90]

One of the things the latest GFS sort of reminds me of is last Feb when we failed to get enough energy going underneath and in the end it was just a rather tame affair with with a big high sat over us which inevitably flattened, is there any chance that we could possibly have a scenario like that again?

[-uksnow-]

The Gulf Stream can be affected by surface winds as it driven by differences in salinity and surface winds.so if a easterly blows out into the Atlantic it will slow down .

This is getting off topic really so i guess i shouldnt post but hmmm, cant resist. The gulf stream as Daniel said is driven by temperature and salinity differences in the water, it goes very deep, a period of easterly winds would have negligable effects, infact so minute effects that they couldnt even be recorded..

[Mucka]

If that was to come off i think all us coldies would be like kids in a candy store, what a chart!!.

Absolutely and just on the edge of Hi Res, so close yet so far.

There are a few good runs but p20 in FI would give that a run for its money.

Hope the admins don't mind me posting this as it is just a bit of fun and only because it is close tot he perfect winter chart. (It's art ya know)

GFS 12z ensembles for SE England.

http://modeles.meteociel.fr/modeles/gens/graphe_ens3.php?x=297&ext=1&y=129&run=12&runpara=0

http://176.31.229.228/modeles/gens/graphe_ens4.php?temp=1&x=298&y=126&ext=1&run=12&runpara=0

Edited February 14, 2013 by Mucka

[-uksnow-]

Ensemles for London

Catching on now..!

[Panayiotis]

This is all we need to get to and this is just 4 days off

http://www.meteociel...96-21.GIF?14-18

Only one way from there

Exactly, what I have been saying since yesterday, as long as the pattern is coming towards us (currently at 96hrs) the cold will follow, people need to understand that.

[Mair Snaw]

Absolutely and just on the edge of Hi Res, so close yet so far.

There are a few good runs but p20 in FI would give that a run for its money.

Hope the admins don't mind me posting this as it is just a bit of fun and only because it is close tot he perfect winter chart. (It's art ya know)

GFS 12z ensembles for SE England.

http://modeles.meteo...un=12&runpara=0

http://176.31.229.22...un=12&runpara=0

WOW. as said just for fun, but you gotta have something to dream of and that chart is as sweet as they come, infact even on valentines day i would sell the wife for a chart like that to verify.

[chris55]

Absolutely and just on the edge of Hi Res, so close yet so far.

There are a few good runs but p20 in FI would give that a run for its money.

Hope the admins don't mind me posting this as it is just a bit of fun and only because it is close tot he perfect winter chart. (It's art ya know)

GFS 12z ensembles for SE England.

http://modeles.meteo...un=12&runpara=0

http://176.31.229.22...un=12&runpara=0

Not massively different from the ECM 00z 240 chart, just shows what is possible now the PV has moved out of Canada!!

[Tom Jarvis]

Where is mr Steve murr hope he hasant had a hart attack after the modeles so far

Edited February 14, 2013 by Tom Jarvis

[Met4Cast]

The Gulf Stream can be affected by surface winds as it driven by differences in salinity and surface winds.so if a easterly blows out into the Atlantic it will slow down .

Why ask a question and then disagree and argue with the answer given?

Good to see the GFS slowly coming on board, fairly decent UKMO, not worth worrying about the position of high pressure at this stage, the overall trend is what's important.

[Tim Bland]

Their latest GM PPN fields later next week offer some (rather diffusely-distributed) snow showers feeding west as far as the likes of Wilts / Oxon etc, but these are modified fields of course (because of known model deficiencies regarding insufficient inland penetration of showers in this sort of set-up). Equally of course, no PPN signal (especially showery) is trustworthy at this range.

Wow quite an upgrade in percieved snow potential from the met office! Hopefully a better long term outlook on tomorrows update then!

[Frosty.]

Where is mr Steve murr hope he hasant had a hart attack after the modeles so far

No he's waiting for the ECM like the rest of us : )

Better Gfs this afternoon, ukmo still on track so all being well another cold spell is on the way later next week, hoping it's an RJS severe wintry blast from the past we end up with.

Edited February 14, 2013 by Frosty039

[bluearmy]

Wow quite an upgrade in percieved snow potential from the met office! Hopefully a better long term outlook on tomorrows update then!

thats just the GM model chart at day 6 tim which, i believe isnt used in much detail by exeter.

each ecm that comes out sees me expecting it to sink the ridge somewhat based on the ens from the previous run and yet the op continues to stand the ridge proud to our north. given that the deep cold uppers are a hit/miss affair for our island next week, i'm looking to see if we can get another cold pool to drop in around the back of the ridge and advect west in the general flow of the block. i dont want to be relying on the euro trough to drive the CAA as we've seen it be slacker come verification so far this winter.

[fergieweather]

Wow quite an upgrade in percieved snow potential from the met office! Hopefully a better long term outlook on tomorrows update then!

No...!! - NO upgrade, just bob-standard fare expected with this sort of set-up and, of course, issue of settling (in any meaningful sense and especially at lower levels) becomes trickier with each advancing day of growing solar input, but especially from the sort of light, diffusely-spread showers progged in the GM fields. As they note, showers will "need watching" closer to the time (i.e., in terms of their distribution and any possible impacts touching towards usual warning criteria), but there's nil in their current assessment that steers away from the broadly dry/cold story they've communicated through mid-latter next week, i.e., nuances of shower distribution aside.