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Dusting of snow forecast for some N and W hills on day 3/4
As fascinating as watching paint dry....Will the UK high pressure bounce to Greenland ?...er wait a minute... no.Will the UK high pressure bounce to Scandinavia ?....er wait a minute..no.It was novel for a while and the dry and sunny days are still welcome but the clock is ticking...February soon and some of us are getting impatient now Phil.
As fascinating as watching paint dry....
Will the UK high pressure bounce to Greenland ?...er wait a minute... no.
Will the UK high pressure bounce to Scandinavia ?....er wait a minute..no.
It was novel for a while and the dry and sunny days are still welcome but the clock is ticking...February soon and some of us are getting impatient now Phil.
Borrowong loosely from Crosby, Stills, Nash & Young:
If you can't have the weather you love, love the weather you have.
Typical deep FI fayre here - disruption undercutting and HLB of sorts, even if its not quite the money shot!
That trough disruption would only have to occur a couple of hundred miles further west and things would start getting pretty interesting!http://old.wetterzentrale.de/pics/Rtavn2881.gif
Even as it is the run ends up on a rather intriguing note, not dissimilar to the GEFS perturbation I linked to from the 12Z.
http://old.wetterzentrale.de/pics/Rtavn3841.gif
Jet forecast to go south, and by quite a long way as well. GFS was hinting at southerly tracking lows earlier.http://old.wetterzentrale.de/pics/Rtavn28814.gif
That trough disruption would only have to occur a couple of hundred miles further west and things would start getting pretty interesting!http://old.wetterzentrale.de/pics/Rtavn2881.gif Even as it is the run ends up on a rather intriguing note, not dissimilar to the GEFS perturbation I linked to from the 12Z. http://old.wetterzentrale.de/pics/Rtavn3841.gif
was hoping to see a bit more of that this evening but still plenty of time for that over the next 48-72hrs!
Yes, I was looking at that earlier and thinking it would not take much of an adjustment west or south to get the trough disruption over the British Isles. There's a pocket of seriously cold air advecting west under the block
http://modeles.meteociel.fr/modeles/gfs/runs/2017011918/gfsnh-1-264.png?18
The 12z ECM run for my area has maxima below 5C and overnight frosts all the way out to Friday week: it's only on Day 10 that we get to 10C and that's a long way off. Interestingly for London the Op had very little ensemble support on Day 10 - virtually a mild outlier and 5C above the mean.
http://www.weathercast.co.uk/meteo/eps/ensemble-tt6-london.gif
JUST FOR FUN: Deep into FI look north and to our east: - if the Atlantic does break through end of next week!?
So the GFS ensembles are fairly set now to the 28th January when we get back into the massive uncertainty that we have had at this range all winter. This still leaves 4-6 weeks approx of a chance of a good cold spell with snow with no clear signals in favour or to the contrary really. I would prefer to see the range of 850 hPa values in FI from 0 to -10 rather than +5 to -5 as now because impending cold always seems to need a few extreme cold runs out there to kick start it!
Based on experience of this winter FI is still at T+144.
Atlantic now looks delayed until 27th January ?
Ignoring what is shown afterwards this chart is showing potential. WAA is more directly thrown north over our neck of the woods with a developing Scandi High/Arctic extension.
A continued westward correction, a few tweaks,a slight undercut, a slice of luck for once and things could start to look very different in a couple of days time.
We shall see.
Based on experience of this winter FI is still at T+144.Atlantic now looks delayed until 27th January ?Ignoring what is shown afterwards this chart is showing potential. WAA is more directly thrown north over our neck of the woods with a developing Scandi High/Arctic extension.A continued westward correction, a few tweaks,a slight undercut, a slice of luck for once and things could start to look very different in a couple of days time. We shall see.
That is some block forecast out there to the east Steve, a wall north to south, its going to take some punch to get through. The Azores high wants to help out later on, but its suggested the Atlantic doesn't make it to the east of us which makes our space a bit of a battlefield between two pressure systems. Could be the southerly flow may inflate the high to east and looking for signals this may happen if low pressure can then drive through to the south.
What the 18z giveth, the 0z taketh away
But FI shows some promise
GEFS has HP still influencing the SE on roughly half the ENS on the 25th,but as you say Atlantic flow winning through by the 27TH with over 80% ENS S westerly/westerly by then.
It's a delicate evolution to get enough WAA to bolster the block, especially when there's high pressure too close to the south west countering trough disruption because you can't get energy into the southern arm of the jet, under the block.
The models keep tweaking the evolution so there's little certainty about how things will pan out a week hence. The Atlantic looks to be waking up but everything continues to slip back.
block a bit stronger
http://modeles.meteociel.fr/modeles/gfs/runs/2017012006/gfsnh-0-138.png?6
In the shorter term the ensembles showing current cold spell in the South continuing for a few days. With maxima 4-5C and nightly frosts around -4C on average and perhaps lower in the next few days it has only really lacked snow.This seems to have slipped through the net a bit and will have lasted over a week before it ends.
http://modeles.meteociel.fr/modeles/gfs/runs/2017012006/gfsnh-0-156.png?6
first attempt fails, but warm southerly winds for us all