Model output discussion 10/02/21

[minus10]

Gfs 18z toying with the idea of plunging us back into the freezer from the north....

 

[Dancerwithwings]

7 minutes ago, feb1991blizzard said:

GFS 18z is a stonker.

A stonker for any time of year but seriously good for late March.

 

Your right for sure, thoughts of 2013 come to mind

 

[minus10]

8 minutes ago, minus10 said:

Gfs 18z toying with the idea of plunging us back into the freezer from the north....

 

Forget toying. Its decided....well for tonight anyway...

Edited March 6, 2021 by minus10

[Allseasons-Si]

My alarm has just woken me up from early hibernation,...

@MATTWOLVES,these are for you buddy...

seriously though,the ops and ens have been showing this of late and it is not unheard of at this time of the year and i would welcome one last blast of cold weather before spring arrives proper

bring it on 

Edit:just to add,...do you see a Lion over Scandi on the latest Sat?

in with a lamb!,..out with a Lion!

 

Edited March 6, 2021 by Allseasons-si

[Iceman2606]

 

Looking very stormy on Thu next week on GFS 18z this evening. Would be 60-70mph gusts widely inland with possible 80mph on coasts if this verified?

Storm Evert to be named possibly?

[geordiekev]

2 hours ago, Dancerwithwings said:

Your right for sure, thoughts of 2013 come to mind

 

Yep, I remember visiting Aviemore for my birthday from Spain where I was living in 2013 and was so chuffed at copious snow.

Quite often I travel to colder climates for my birthday just after mid month only to find it's snowing at home.

Could it be another snowy 18th, it's certainly a watching brief

[Jordan S]

Morning

Just a quick update on the now likely storm for wednesday night into thursday morning.

it's likely the storm will develop quickly out in the atlantic with wind gusts of 80-90mph on the southern and/or southwestern quadrant.. before these lessoning as it approaches the UK.

Here's the Gfs, Gem and Ecmwf..

Gfs..

Gem..

Ecmwf..

The low pressure system moves quite quickly northeast as it crosses the country with the centre probably moving over Scotland and the strongest winds to the south through Ireland into England and Wales, although a little uncertainty with the exact track.

winds becoming very strong with gusts of 50-60mph probable quite widely inland, with 60-75mph for some parts of the west and southwestern coasts of England and Wales.

Icon as an example..

As much as 50-80mm of rainfall accumulating on the hills of Wales, northwest England and western Scotland too altogether from late Tuesday/midday thursday.

Edited March 7, 2021 by jordan smith

[Tim Bland]

Good agreement in high pressure by day 10. Just the ECM this morning that has it far enough west for a northerly ... 

[mushymanrob]

Maybe tentetive signs of something a little more settled beginning to emerge in the 8-14 day timeframe?

 

[Frosty.]

I’ve been banging on about this for days now..was probably talking too myself?.well I am autistic!..but anyway, there are continued signs..indeed, increasing signs..that the last third of March could become more settled?!  

Edited March 7, 2021 by Jon Snow

[minus10]

12 hours ago, minus10 said:

Forget toying. Its decided....well for tonight anyway...

yes this morning shows the constant volatility with the gfs going from a northerly on yesterdays 18z to a westerly on 0z to now a warm south easterly on 6z. This is a signal that seems to be growing however a colder snap cannot be ruled out yet. The wind this week will be the issue.....

[Frosty.]

The increasingly settled longer term trend continues on the GEFS 6z mean..sure there’s still some crud?..isn’t there always!..but the general direction of travel (just a small sample shown here)...is towards something less unsettled / more settled by the last third of March..which may include Easter!  

 

[damianslaw]

13 hours ago, minus10 said:

Forget toying. Its decided....well for tonight anyway...

Would force people to stay in and complete the census!

[phil nw.]

Yes Karl some promise of a drier period after the unsettled spell but the main focus this coming week continues to be a wet and windy period especially around Tuesday to Thursday as a strong jet heads this way.

Jet stream chart and the fax for Weds. 12z shows the general picture.

Quite cold air sourced from Greenland follows for the end of the week with a brisk westerly showery flow after the low passes.

Plenty of snow showers higher up over Scotland and perhaps over higher ground further south.Temperatures back down again to single figures after a brief milder interlude around mid-week.

As already touched on there are signs of rising pressure again in the ens for week 2 especially further south.

GFS 06z ens

Safe to say though that there are indications of some improvement in week 2 with little rainfall showing in those ensembles.

 

 

[SqueakheartLW]

The different faces of Easter Sunday based on today's GFS Extended Run

We all know how variable the weather can be in early to mid spring when warmth is building to our south but the cold air is still very much in place to our north and the source of our air can make a very big difference at this time of the year between very cold with single figure maximums and frost and snow a threat to warm and sunny with 20C or even more possible in the warmest setups.

Think back to last early April when at one point it looked like we were heading into the freezer

31st March 2020

At this stage we are under high pressure with generally slightly cooler than average temperatures, the legacy of the cooler weather that had set in behind the last area of low pressure which was then trapped under the area of high pressure but very cold Arctic air is gathering way up to the north near Greenland and this is about to build up and head south towards the UK

1st April 2020

High pressure begins to lose its grip over the UK as it begins to pull out into the Atlantic and at this stage it looked like we were about to open the floodgates to that very cold Arctic air that is making its way towards the UK from Iceland and Greenland and after such a dire winter 2019/2020 for snow this was looking like the best period for potential snow coming up. This day was less cold as the air was stirring up in the higher wind speeds combined with less cold Atlantic air moving in too

2nd April 2020

At this stage we had all the features more or less in the right place to get that cold Arctic air into the UK and looking at the 500mb chart it looks almost perfect with that big Greenland high and Scandi trough but the big spoiler feature is that last little bit of heights just sitting to our west. The cold air has made it into Scotland and the northern Isles but this is as far as it ever got as you see the big bust in the next couple of days all because of that little spoiler high pressure area.

3rd April 2020

Although the Greenland High and Scandi trough are still there it is not doing us any favours getting the cold air in as the spoiler high I mentioned on the previous day has collapsed back into Europe and instead this is now opening the gates to much warmer air from the south instead so the cold stays trapped in the far N whilst temperatures are beginning to rise further S.

4th April 2020

Milder air is now pushing north and in turn pushing any last hopes of a late save for that dreadful 2019/2020 period for snow away. This generally sets the trend for April 2020 with milder than average and much drier than average temperatures overall. Shame we couldn't keep the dry theme for Summer 2020 however

Now to get onto the GFS Extended charts for Easter Day 2021

I particularly focused on what happened early on ln April 2020 as the following charts show what can happen if this comes off as well as if we get the opposite extreme. I have picked out the two coldest charts for Easter Sunday today as well as the two warmest ones just to show you how different things can be. They are based on 12pm and the point in the day with the highest 2m temperatures on the runs.

The cold faces of Easter Sunday

GFS Extended Member 15     850hpa temp -8.1     2m temp 1.3

This chart is a cold lovers dream at any point in the winter, let alone early April and temperatures are very low as well. A daytime maximum of just 1.3 in Scunthorpe but some parts of Scotland as well as parts of the Midlands look to be at or below 0C. Very cold 850hpa temps for the time of the year too at -8.1. The pressure pattern itself looks to be a real snow maker for England and Wales in particular away from the far south which is in less cold air with a threat of some persistent snow and based on that region of 0C temps it looks like the Midlands is in the firing line for the snow. Scotland and N Ireland could see snow showers in the cold air to the north of the fronts. When you look at the 500mb chart you can follow the isobars back and see just how far that cold air has come from. It looks to be of Siberian origin.

I would call this one the Snowy Face of Easter Sunday

GFS Extended Member 4     850hpa temp -11.4     2m temp 3.0

Another cold looking set of charts to conclude the cold section of my post. This one has a cold Arctic northerly blast just in time for Easter. 2m temperatures aren't quite as low for England and Wales here with 3.0C for Scunthorpe but probably 4's and 5's for the south but like with the previous option around 0C for Scotland. 850hpa temps are however lower in this option compared to the first so probably more unstable air and with convection likely to play a big part here due to April sunshine then snow showers could be triggered just about anywhere by day and continue at night in exposed regions. The 500mb chart is a cold lovers beauty and with that small trough near Iceland that could easily dive SE and create more persistent snow.

This one I could call the Arctic Blast Face of Easter Sunday

The warm faces of Easter Sunday

GFS Extended Member 13     850hpa temp +5.6     2m temp 13.6

The first of my warmer charts to show you but not everyone is warm here. 2m temps show a large contrast between the north and the south with temperatures struggling to get to 6C in Scotland whilst the south is seeing around 18C. A lot of this could be down to low cloud coming in off the North Sea in the gentle easterly winds and keeping temperatures low whilst the south is in the drier continental feed so will likely be sunnier and as a result much warmer. This is very much a typical April easterly with dry weather and low cloud

I would call this one the Typical Face of Easter Sunday

GFS Extended Member 28     850hpa temp +6.0     2m temp 16.8

The final set of charts reminds me somewhat of some of the weather patterns we saw in April 2003 with warm air pushing in from the south lifting temperatures widely into high teens and low 20's quite often. This 2m temp chart shows widespread above average temps with 16.8 at Scunthorpe but no doubt even higher further south. 850hpa temps are also warm for April too but this is by no means a totally settled pattern with low pressure close to the NW so a threat of rain here but the SE should be dry and warm.

This is the Summer like Face of Easter Sunday

[offerman]

17 hours ago, Allseasons-si said:

My alarm has just woken me up from early hibernation,...

@MATTWOLVES,these are for you buddy...

seriously though,the ops and ens have been showing this of late and it is not unheard of at this time of the year and i would welcome one last blast of cold weather before spring arrives proper

bring it on 

Edit:just to add,...do you see a Lion over Scandi on the latest Sat?

in with a lamb!,..out with a Lion!

 

Reminds me of a cloud , Lion smoking a fat one I caught a few years ago :-). 
 

 

[minus10]

After the stormy interlude gfs 12z is indicating an anticyclonic warm spell followed by an anticyclonic cool spell. The theme is there, just how it plays out is still to be finalised...

 

Edited March 7, 2021 by minus10

[feb1991blizzard]

Ice days with an almighty blizzard anyone??

[stodge]

Evening all

One of those typical spring days where it's warm in the sun and out of the wind but pretty cold in the wind and out the sun. Nothing unusual in that - nor in the immediate evolution to a more unsettled pattern in the next week. From there, indications continue of a renewed rise in pressure over or close to the British Isles as we move into the second part of March.

Let's look at this evening's meteorological entrails.

T+144 and T+240 from GEM, GFS OP and GFS Parallel respectively:

T+144 (March 13th):

T+240 (March 17th):

The overall pattern pretty well set with an active trough to the north of the British Isles at T+144 bringing strong WNW'ly air flow according to the American models and a more WSW'ly according to GEM with the trough elongated more to the south over the British Isles. Heights duly build from the south west and both GEM and Parallel end with the core of heights over the British Isles by T+240. OP keeps a much stronger northern arm to the jet and that maintains heights over Europe and the British Isles continues in a mild SW'ly.

Moving on with the T+312 and T+384 charts from GFS OP, Parallel, Control and CFS:

T+312 (March 20th):

T+384 (March 23rd):

Once again, it's the old question of where do you put the HP? Parallel ends up fantastic for cold fans with the HP over Scandinavia and a decent late cold wave. Control is much slower and OP brings back the Atlantic pretty quickly. The rise in heights from T+240 looks set but where it all ends up is still a long way from resolution.

 

[SqueakheartLW]

1 hour ago, feb1991blizzard said:

Ice days with an almighty blizzard anyone??

Member 14     850hpa temp -13.8     2m temp at 12pm -0.8

Just seen this one. Looked at 2m temps on wetterzentrale and it stays below freezing all day in many places

Look at that big area of 0C or lower in central UK especially and it only gets colder later in the day too

Member 24     850hpa temp 4.0     2m temp at 12pm 15.7

What a contrast to the warmest option at the same time

[cheshire snow]

Looking at the day 10 upper temperature profile on this evenings ECM +10 over West Ireland to -3 over East Anglia feeling very spring like in Ireland but still a chill in the air in the east of the uk All at day ten so almost unlikely to verify.

C.S

[damianslaw]

A change is afoot in the next 24 hours after a lengthy predominantly dry quiet spell under anticyclonic conditions, the atlantic is set to come back with some gusto. A feature of the winter just gone has been a lack of relatively stormy conditions, come mid-week strong winds and gales are forecast for some, thanks to a strong jet tracking through the UK. Heavy rain for many as well, which will make for rather unpleasant conditions. Colder uppers also moving in towards end of the week, despite winds being westerly the air source is the arctic, could be a fair bit of wintry precipitation over relatively modest levels in the north, sub 528 dam air, even a pocket of 522 dam air shown on ECM. 

As we move into the middle of the month, signal for heights to build in behind the atlantic trough quite quickly, we could easily revert back to what we have seen so far this month, not easy to pinpoint where heights might eventually end up, there is a sign of quite an amplified flow, so they could build into scandinavia, or just sit over the UK. 

A rather typical March could be on the cards with an interplay between the atlantic and something much drier and anticyclonic.

[Jordan S]

The outlook for next weekend still remains an unsettled one with showers some perhaps wintry in the north on Saturday before it possibly becomes slightly milder by Sunday and a chance of a longer spell of rain, windy too.

GFS..

GEM..

 

For the first half of next week upto wednesday at least and apart from possible initial rain in places on monday, higher pressure likely moving north from the south into at least central,southern England and Wales with the unsettled weather most likely becoming confined to Scotland and possibly northern Ireland by tuesday and wednesday with the continued chance of rain at times aswell as the potential for strong winds here.

areas further south especially southern parts of England and Wales will likely become mostly settled. It probably also becomes milder for most or all.

Edited March 8, 2021 by jordan smith

[IDO]

As expected just a brief westerly interlude before pressure rises again in our locale:

London> 

Still some variation on the theme of HP and timing but we are again looking at another 5-7 day settled period post d7. ECM, late to the party but finally got there yesterday whilst gem and gfs have been consistent in FI with this. The gefs mean d8-16:

Wed-Thursday still looking stormy with some high gusty winds:

 

Worst of the rain in the NW and West (^^^acc by d4).

[minus10]

Surprised there arent more weather warnings from the met office re wind Wednesday and Thursday yet? This has been signalled for quite some time now. Maybe they will be issued this morning. After a long quiet spell it will definately be a noticeable change...

Edit: they have now been issued. 

Edited March 8, 2021 by minus10