Model Output Discussion - Snow Watch limited edition

[Purga]

Average to possibly coolish at times And pretty unsettled. Certainly nothing of any wintry note to come apart from the high ground i the north maybe at first.

[nick sussex]

The MJO composite for phase 7 in March is this .

Not far off the trend of the outputs . Positive anomalies to the north and nw , lower heights to the sw .

The issue is how far north south the jet is . It’s too early to rule out another cold snap .

Of course we’re getting later into the month . Personally I’m not a great lover of spring cold and marginal snow but that’s still a possibility.

 

 

[Stuie]

Come Sunday, snow is dropped from the menu and replaced with plenty of water cress. Saturday is the last day any cold uppers cover the country.  Post that stuck in a west based NAO with a conveyor belt of LP`s. Can`t see what could change to stop that.

 

 

Edited March 9, 2023 by Stuie

[brabs69]

West Haddon, Northamptonshire 

[Stuie]

Still a small signal for something wintry tomorrow morning/lunch as the LP exits. Looks like the tank is empty via the Arpege. Can`t see the GFS outlook (blanket snow).

The 528 DAM does skirt EA.

EDIT: The Arome does have a heavy precipitation exit, might be a surprise around lunch.

Edited March 9, 2023 by Stuie

[nick sussex]

3 minutes ago, Robbie Coldrain said:

And with this epic cold rain spell coming to an end. It's time time to start looking for the first 70F. 

 Very funny ! It was pants here aswell . I’d not rule out more cold rain though !

The models are still messing about in the medium term . I wouldn’t totally give up home of some snow during March for those unlucky over the last few days .

[Spurry]

Started Snowing in wigan about an hour ago,looks to be getting heavier now 

[DJ Fart]

1 hour ago, Stuie said:

See what happens over here in EA soon. Marginal dew point.

I'll give you a clue, mate: nothing.

[andy989]

Blizzard here. Started about 5:am. Hard to get an accurate measure as it’s the fine “blowy about” kind of snow. 

[DJ Fart]

That's

1 hour ago, brabs69 said:

West Haddon, Northamptonshire 

Now you're talking. Very nice!

[MJB]

35 minutes ago, brabs69 said:

West Haddon, Northamptonshire 

And you aren't that far from Banbury 

 

Banbury Snow

Bicester Rain

Edited March 9, 2023 by MJB

[RhHh]

22 minutes ago, MJB said:

And you aren't that far from Banbury 

 

Banbury Snow

Bicester Rain

Lousy parkers in Bicester!!

[ANYWEATHER]

I would imagine after a very dry spell plenty of water going into the streams ,rivers and reservoirs after the snow melt for some places and the copious amounts of rain to be falling in the days ahead. May go from snow watch to rain watch ! Anyway looking forward to some milder weather, 14c would feel tropical at the moment....

[johnholmes]

For net wx 0900 Thur 9 th March 2023

Looking at the 3 charts I have on my daily check on the NOAA output, there has been a slow increase in the contour heights from north to south. The latest shows the 540DM line just about on the Scottish border.(see below). The air with that still originates from fairly high latitudes over the Pacific and ne Russia so not especially mild. A 546DM contour is shown over southern England.

 

With these charts being very consistent in their evolution I am pretty confident they will be shown to be about ‘right’ 6 days from now. So the deep cold has certainly been moved well north with even much of Scotland in the slightly less cold air. Turning to the 8-14, covering the period 16-22 March and the pattern remains much as the 6-10, the 540 DM is now over northern Scotland with the 546DM still over southern England.

This all suggests that snow is going to become confined to the highest hills of northern England with only the far north of Scotland likely to be seeing any snow falling below about 5-800 ft. That is when there is any ppn! Turning to the ECMWF 10 day charts by the 13th onwards and the 850 MB charts show the -5 C line moving to the north of Scotland before returning to the south of Scotland by the 19th. As is often the case EC and NOAA are not on the same page so to speak but not on different chapters. Overall, along with the synoptic outputs from the 3 main models I would suggest that PM air with surface flow from a westerly point is the weather pattern 6-14 days from today. Neither very mild nor very cold weather patterns are likely for any period.

Of course I may be talking nonsense but then weather forecasters can only do their best with outputs at their disposal; egg on face is a professional hazard so bear with UK Met as they grapple with the next 72-96 hours let alone beyond.

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

[snefnug]

Have some piccies!  Amber warning finally issued for North Wales Marches.   

[StingJet]

53 minutes ago, andy989 said:

Blizzard here. Started about 5:am. Hard to get an accurate measure as it’s the fine “blowy about” kind of snow. 

Been air snowing since day break here Andy on Ynys Mon ,  we are about 400' ASL ,  It has been sticking ,  but marginal atm,  couple of hills to the North @ 800' ASL  are now white .. the forecast for my spot is sleet , but been Snow thus far ..  even on the School run this morning down to Valley , closer to sea level was air snow , but not sticking. Will be interesting to see what the heavier precip delivers later ,  and overnight when the LP shifts east and drags back in the wrap-around northerly  

First "proper" snow fall for here for years, probably since the 12" dumping winter 2012/2013  

Edited March 9, 2023 by StingJet

[Drifter]

1 hour ago, nick sussex said:

The MJO composite for phase 7 in March is this .

Not far off the trend of the outputs . Positive anomalies to the north and nw , lower heights to the sw .

The issue is how far north south the jet is . It’s too early to rule out another cold snap .

Of course we’re getting later into the month . Personally I’m not a great lover of spring cold and marginal snow but that’s still a possibility.

 

 

Now I’ve had my snow (enough for a snowball fight with the kids yesterday) I want to start looking for some warmth in the charts now. Got plenty of jobs I want to do outside but too damp and cold for that now!

Need to pin my hopes on an Azores ridge I guess. 

[LRD]

Snowed here for 24 hours on and off and it's barely settled anywhere. Patchy on rooftops, some covering on the grass/fields, next to nothing roads/pavements

As I suspected and said elsewhere on here, this 3-day wonder (IMBY - I realise that, for example, Scotland and some other northern areas has been colder/are going to remain cold for longer) is looking pretty wintry for higher places but for many low lying locations it's a slushy, wet, sleety, snowy mess. Awful. If only it was December, it'd be much more convincing I suspect

At least it's on its way out by Saturday evening/Sunday morning

[andy989]

6 minutes ago, StingJet said:

Been air snowing since day break here Andy on Ynys Mon ,  we are about 400' ASL ,  It has been sticking ,  but marginal atm,  couple of hills to the North @ 800' ASL  are now white .. the forecast for my spot is sleet , but been Snow thus far ..  even on the School run this morning down to Valley , closer to sea level was air snow , but not sticking. Will be interesting to see what the heavier precip delivers later ,  and overnight when the LP shifts east and drags back in the wrap-around northerly  

First "proper" snow fall for here for years, probably since the 12" dumping winter 2012/2013  

I’m about 1000’ASL on the side of Elidyr Fach/Fawr. My house is often on the mountain snow line so we usually do well. The lane was starting to drift over as I was leaving for work so I suspect I won’t be able to drive to the house at the end of the day. Light rain down in Caernarfon though. Hope you get some accumulation later

[johnholmes]

some may enjoy book marking this link for some web cams mainly Derbyshire+, the heavier snow not really reaching there so far, Flash at 1500 ft showing the most (Staffordshire).

Peak District Webcams

WWW.JAMESGPHOTOGRAPHY.CO.UK

---

A collection of Peak District webcams highlighting current weather and road conditions. Useful for planning photography trips in the Peak District.

 

[nick sussex]

1 minute ago, Drifter said:

Now I’ve had my snow (enough for a snowball fight with the kids yesterday) I want to start looking for some warmth in the charts now. Got plenty of jobs I want to do outside but too damp and cold for that now!

Need to pin my hopes on an Azores ridge I guess. 

Great that you managed that snowball fight . At the moment the jet looks like tracking quite close to the UK . The uncertainty is really exactly how far south that might come so the weather could be anything from cool wet , to colder with a continued risk of snow .

[Phil Blake]

3 minutes ago, nick sussex said:

Great that you managed that snowball fight . At the moment the jet looks like tracking quite close to the UK . The uncertainty is really exactly how far south that might come so the weather could be anything from cool wet , to colder with a continued risk of snow .

I think a fair assumption is it'll probably be fairly mobile with milder/colder shots as systems move through

[Ali1977]

That’s another system coming in on Friday, some snow for Cornwall and Devon - hopefully it comes further east 

[GokouD]

Proper snow here in Telford. Apologies to the snow starved!

 

[Stuie]

23 minutes ago, johnholmes said:

For net wx 0900 Thur 9 th March 2023

Looking at the 3 charts I have on my daily check on the NOAA output, there has been a slow increase in the contour heights from north to south. The latest shows the 540DM line just about on the Scottish border.(see below). The air with that still originates from fairly high latitudes over the Pacific and ne Russia so not especially mild. A 546DM contour is shown over southern England.

 

With these charts being very consistent in their evolution I am pretty confident they will be shown to be about ‘right’ 6 days from now. So the deep cold has certainly been moved well north with even much of Scotland in the slightly less cold air. Turning to the 8-14, covering the period 16-22 March and the pattern remains much as the 6-10, the 540 DM is now over northern Scotland with the 546DM still over southern England.

This all suggests that snow is going to become confined to the highest hills of northern England with only the far north of Scotland likely to be seeing any snow falling below about 5-800 ft. That is when there is any ppn! Turning to the ECMWF 10 day charts by the 13th onwards and the 850 MB charts show the -5 C line moving to the north of Scotland before returning to the south of Scotland by the 19th. As is often the case EC and NOAA are not on the same page so to speak but not on different chapters. Overall, along with the synoptic outputs from the 3 main models I would suggest that PM air with surface flow from a westerly point is the weather pattern 6-14 days from today. Neither very mild nor very cold weather patterns are likely for any period.

Of course I may be talking nonsense but then weather forecasters can only do their best with outputs at their disposal; egg on face is a professional hazard so bear with UK Met as they grapple with the next 72-96 hours let alone beyond.

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

Good read John, thanks.  2 of my posts back these were my thoughts also (but nowhere near this level of language).