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Very happy with this afternoons GEM and UKMO, GFS poor early but looks to be setting up another day 10 + special.
Originally Posted by: Ally Pally Snowman
Indeed
The T850 mean has certainly shifted up significantly since the 0z after being consistently flat around -5 for a few runs. Quite a few milder members in there.
Originally Posted by: RobN
Yes the enthusiasm is still there but no question the 850 ensemble mean has risen in the last few runs. It's going to get cold but I would still say there is a lot of conjecture as to how cold. I've seen better situations than this fail before now.
http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=312&mode=0
I have noticed a few times that while GFS op runs are good at picking up patterns at a long way out when the time period approaches it seems to be less consistent on the details from run to run or day to day.
Your thoughts Steve ukmo
Yes , with a lobe of blocking to the North & North East the 168 chart would be very cold at the surface-
GFS has trended to the Euro but not quite-
GEM 192 ( similar profiles to UKMO 144 ) has a big snow event-
Originally Posted by: Steve Murr
I know it’s only a model, but sub 500 dam air over Manchester at +264 hours is rather on low sidehttp://www.meteociel.fr/modeles/gfse_cartes.php?&ech=312&mode=0
Originally Posted by: Surrey John
Thickness ~520 DAM
Thats the 500hPa height, the 500-1000hPa thickness value is around 528dam at that time point for Birmingham based on that chart.
Edit: Sorry I got confused as you posted a 312hr chart, as Steve says the 500-1000hPa value us around 520dam at 264hr.
Originally Posted by: Polar Low
Definite snow event for the North especially with a bit of elevation-
Its a pity no 168 chart, but the wedge of High pressure would see that low exit around IOW & deeper
cold coming back SE - similar to ECM 00z
We know that the GFS has an Eastwards bias, particularly in situations like this so let's see what the ECM does later.
Is that the GFS 12z? Thickness values at 264 are a long way above 500 dam?
Originally Posted by: Shropshire
I may be wrong but I have a feeling the GFSP may have corrected that a bit (although it may too early to dete,one that with enough statistics).
UKMO 12z / ECM 00z Quite similar across the piste-
Lets hope ECM looks same as UKMO tonight so we can see the evolution-
Maybe some snow up over the staffordshire hills-
GFSP looking much more like UKMO at T+144.
Originally Posted by: Arcus
Yes, dropping the shortwave West.
Yes there is a marked doffernce between the GFS op and GFSP at 144hr. Here are the t850s below for the the GFS op and GFSP respectively.
GFSP 12z looks similar to the GFS by 228, although it takes a different route to get there.
https://www.theweatheroutlook.com/twodata/gfsp.aspx?run=12&charthour=216&chartname=mslp500&chartregion=na-region&charttag=500hPa%20GPDM
I find it wise to never completely dismiss a run or model but once again the gfs strat profile very different to that of the ecm at 30mb t240.
The ecm has the vortex over Canada wound up in a tight ball where as the gfs has it in a long oval circle aligned west to east across Greenland and Iceland which would flatten the pattern more.
If the ecm sticks to its guns then I would expect to see much more in the way of amplification an a Iceland/ Svalbard high.
Certainly some really good options in GEFS
P snow flurries along the east coast, s/e by 132 until 186
Followed by a dump across the UK as a chunk of the vortex swirls over us!
http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=312&mode=16&runpara=1
That's quite a few parallel runs over the past couple of days which have blanketed the UK in snow. The outgoing 6z run also had a covering pretty much everywhere.
(Bear in mind due to the low pressure involved the 850 level is much lower than usual, hence we don't need -10s to pretty much gaurantee snow...)
The only rational explanation I can think of is that the new GFS model has been funded at least in part by Carlsberg.
Originally Posted by: doctormog
It must have been! That 12z parallel GFS is the snowiest run I've seen so far this winter.
(There's a pixel of >50cm snow depth over the Pennies by 336.)
Originally Posted by: Gooner
And another insane Para