OP and control ...let's hope they are sniffing something out for early Feb..

Mild, chilly, mild, cold?

Can the GEFS countdown a cold spell from 300+ hrs out ,possible but unlikely.  

Looks very wet as well so flooding on the menu. 

 

 

 

Given that the "chilly" was initially modelled as "cold" then perhaps mild, chilly, mild, chilly is more likely by the time we get there?

I'm hoping not, this time around but, as we're all seeing, there's still a huge amount of variability from one run to the next beyound around 144hrs.

 

 

Given that the "chilly" was initially modelled as "cold" then perhaps mild, chilly, mild, chilly is more likely by the time we get there?

I'm hoping not, this time around but, as we're all seeing, there's still a huge amount of variability from one run to the next beyound around 144hrs.

I'd agree, sadly it's a very poor outlook for southern snow fans. There's also a chance of some exceptionally mild weather between 26th and 30th.

Still think the likelyhood of an early February 1978 style cold is the most likely route to very cold conditions in UK this winter especially to the south.east.

Still think the likelyhood of an early February 1978 style cold is the most likely route to very cold conditions in UK this winter especially to the south.east.

Only a week or two ago it looked as if a January 1940 was on the cards but the models like to tease at long range...

 

Only a week or two ago it looked as if a January 1940 was on the cards but the models like to tease at long range...

Yes we're firmly in Murray Walker territory now. 

 

Yes we're firmly in Murray Walker territory now. 

Only a month to go and then it will be Kenneth Wolstenholme territory

Still think the likelyhood of an early February 1978 style cold is the most likely route to very cold conditions in UK this winter especially to the south.east.

As long as it is not followed by a 1978 style summer. 1978 (trevorharley.com)

 

Only a month to go and then it will be Kenneth Wolstenholme territory

Indeed. 

Actually Feb 1978 looks like a really weird set-up synoptically. Trevor Harley talks about a Scandi high but in fact by the time of the blizzard on the 19th-20th there was a big Scandi trough and a weird thin ridge of high pressure to its west that somehow managed to act as a block to the Atlantic. Never seen anything quite like it to be honest.

Assuming this chart is accurate: https://www.wetterzentrale.de/maps/archive/1978/era/ERA_1_1978021918_1.png

It just shows how everything has to be exactly just so on an island with maritime weather. In our case even the feeblest of Greenland highs worked for us because it was so precisely east-centred. A few miles either way, and we would have been moaning that winter is over and we can't get decent snow here any more.

 

 

Given that the "chilly" was initially modelled as "cold" then perhaps mild, chilly, mild, chilly is more likely by the time we get there?

I'm hoping not, this time around but, as we're all seeing, there's still a huge amount of variability from one run to the next beyound around 144hrs.

Still? Find me a time when it wasn't thus. Those times are rare.

 

Still? Find me a time when it wasn't thus. Those times are rare.

I think it is a fair statement, in the summer months when we have large HP cells floating around you can certainly more accurately predict as far as 5 days ahead.  The point is the jet stream is meandering, active and proving hard to model, this is exactly the scenario where models will flap about at that range. 

Still a big disparity between the op GFS and the parallel GFS regarding the extent of any snow in the south over the weekend.

Old GFS has very little:

while the parallel gives a good covering for many away from the extreme south coast:

The higher resolution of the parallel is noticeable in these ppn maps, but whether the performance will be any better remains to be seen!

We can actually test the performance much sooner than that. By 42 hours the parallel has a lot of snow in NW England and Wales:

while the main GFS run has next to nothing:

I suspect the parallel is overdoing things! None of the high-res models suggest anything like that on Thursday.

The higher resolution of the parallel is noticeable in these ppn maps, but whether the performance will be any better remains to be seen!

The highest resolution data sets available for both versions are 0.25 degrees. 

We can actually test the performance much sooner than that. By 42 hours the parallel has a lot of snow in NW England and Wales:

while the main GFS run has next to nothing:

 

I suspect the parallel is overdoing things! None of the high-res models suggest anything like that on Thursday.

Does the iPhone use GFS? I’ve noticed it’s been so poor recently. Some days it’s had snow and then removed them at the 11th hour.

I remember that cold snap started with some very heavy dry snow showers on the Friday I was 12 at the time and couldnt concentrate on my lessons looking out the window at the heavy prolonged snow showers accumulating Back on subject more as we head into Feb a similar high could upset the so call return to zonal forcasts predicted and actually produce some winter weather to places that have missed out so far, could be a SW blizzard block ( unlikely on recent form), a slider low or a short term sneaky encroach of colder uppers following a blocked retrogressed trough .

 

Actually Feb 1978 looks like a really weird set-up synoptically. Trevor Harley talks about a Scandi high but in fact by the time of the blizzard on the 19th-20th there was a big Scandi trough and a weird thin ridge of high pressure to its west that somehow managed to act as a block to the Atlantic. Never seen anything quite like it to be honest.

 

Assuming this chart is accurate: https://www.wetterzentrale.de/maps/archive/1978/era/ERA_1_1978021918_1.png

 

 

The highest resolution data sets available for both versions are 0.25 degrees. 

Is that so? That's surprising as the Meteociel ppn charts appear much more detailed with the parallel run. Maybe they are interpolating somehow.