Jump to content
Holidays
Local
Radar
Snow?
Paul

Model output discussion - here comes the beast!

Paul

Please only post model discussion in this thread 

For more general chat and banter, or moans and ramps loosely around the models, please head to the banter thread:
https://www.netweather.tv/forum/topic/86721-model-moans-ramps-and-banter/

For general weather chat including about the snow/cold chances around the country, please go to the regional threads:
https://www.netweather.tv/forum/forum/142-regional-discussions/

We also have a special post SSW cold spell discussion open here:
https://www.netweather.tv/forum/topic/89358-ssw-related-cold-spell-will-it-wont-it/

Thank you!

Message added by Paul

Recommended Posts

3 minutes ago, That ECM said:

Post the models that show what you are describing. 7c Friday 10c weekend. 

On a iPhone but look at hi-res gfs 00z along the south coast, 7c Friday, 10c by Sunday. Yes colder inland but snow highli unlikely south of the M4 by Saturday.

 

Share this post


Link to post
Share on other sites

I mentioned about the perceived perception of blocking being difficult to move, gfs 00z firmly debunks this theory again as the mean of the ensembles moves from -15.1c to -1c in 30 hours along the south coast.

Edited by Paul

Share this post


Link to post
Share on other sites

Just a note of caution on reading too much into the models past 240hrs or so. We do have yet another SSW event ongoing off Canadas atlantic coast. Like the last SSW 10days ago or so it look the models a while to input that into the runs. For me it looks like it hasnt done so so just yet. If the mild returns it will be brief. I suspect it wont and in turn we shall have more Nly outbreaks of cold wrather. If you want a year that was similar try March 2006 or 2013.... brrrrr. 

Share this post


Link to post
Share on other sites
10 minutes ago, Alderc said:

On a iPhone but look at hi-res gfs 00z along the south coast, 7c Friday, 10c by Sunday. Yes colder inland but snow highli unlikely south of the M4 by Saturday.

 

Have a look at AWD post, viewing on a phone is probably causing you confusion. The chart below is for Thursday. 2m temps showing 4c just over the sea and along the coast. They are not as accurate right on the coast.

IMG_0623.PNG

Edited by That ECM

Share this post


Link to post
Share on other sites
3 minutes ago, AWD said:

Green 850hpa air into the south on Friday;

132-7UK.thumb.gif.dbdfae453a1282502b5d36971fefdb51.gif

Nooooooooooooooooo, it's going to be mild, any snow is going to melt.

But wait, surface temps for the same time;

132-778UK.thumb.gif.78c5457cfacc1d791493742588792205.gif

It's still cold.  Any snow might not melt.  Wooooohoooooo.

There's more to temps/snowfall than the 850hpa temps you know.  :pardon:

Those are indicative of freezing rain possibly? falling onto already frozen ground?

Share this post


Link to post
Share on other sites
1 minute ago, Alderc said:

I mentioned about the perceived perception of blocking being difficult to move, gfs 00z firmly debunks this theory again as the mean of the ensembles moves from -15.1c to -1c in 30 hours along the south coast.

Where's the blocking to move? The main block is to the NW by the time low starts pushing up. The low is not coming up against a block to its northeast. 

Share this post


Link to post
Share on other sites

Looking at the GEFS 00z mean, the north, especially scotland stays very cold with snow for the next few weeks..enjoy!!:shok::cold-emoji::)

Share this post


Link to post
Share on other sites

So models now starting to firm up more regarding the low pressue. 

GFS picked the signal up really well yesterday and it appears ECM has moved towards the GFS overnight, with mild air now looking likely to creep into the south, south east.

Strange on how a number of people here shot it down yesterday even though there was major agreement within the 6z GFS suite.

As things currently stand anyone north of the M4 could be in for a decent event.

 

 

Share this post


Link to post
Share on other sites

Yeah Darren I'd say there is a higher then normal chance along that south of M4 corridor for freezing rain. If it came off(especially if it came after the snow) all it will does is make an utter ice rink and with it some really dangerous conditions. I don't think people would know how to deal with it as its so rare in this country as this is just about the only situation that gets cold enough for it to occur...basically we are playing by east coast states rules for a short period of time on the first front due to the surface cold.

GFS ensembles still quite uncertain with some going for all snow, a majority go for snow-rain in south and the rest go with snow in Midlands north (thatis the smallest cluster for sure)

Edited by kold weather

Share this post


Link to post
Share on other sites
7 minutes ago, Alderc said:

On a iPhone but look at hi-res gfs 00z along the south coast, 7c Friday, 10c by Sunday. Yes colder inland but snow highli unlikely south of the M4 by Saturday.

 

Hi Alderc, yes I agree with you on the blocking, I remember 2010 when it was minus 7C here on the Friday night but plus 10C on the Saturday at lunchtime!

With the temperatures, you are right as far as Bournemouth is concerned but it is very close - it's still below 2C not a 30 minute drive from you.

It's a really close thing. A very, very small correction could mean everyone stays cold throughout. As it stands, Northern areas will.

Share this post


Link to post
Share on other sites
6 minutes ago, That ECM said:

Have a look at AWD post, viewing on a phone is probably causing you confusion.

Pretty sure that’s 7c along the south coast. 10c by Sunday.

C266C91C-62E7-4083-87EE-1635E642FE4B.png

DDD23E36-3148-4A32-A41F-24435642FC80.png

Share this post


Link to post
Share on other sites
3 minutes ago, Man With Beard said:

Hi Alderc, yes I agree with you on the blocking, I remember 2010 when it was minus 7C here on the Friday night but plus 10C on the Saturday at lunchtime!

With the temperatures, you are right as far as Bournemouth is concerned but it is very close - it's still below 2C not a 30 minute drive from you.

It's a really close thing. A very, very small correction could mean everyone stays cold throughout. As it stands, Northern areas will.

Absolutely, a correction of 100miles south with the low sliding into the continent would yield incredible results however almost all models are coming on board with a more progressive theme.

Share this post


Link to post
Share on other sites

Still way to early to make definitive statements regarding whether the snow at thurs/fri turns to rain or not. Micro movements in pressure systems and fronts plus the availabilty of a dry continental feed at ground level wil ensure this probably goes down to the wire.

Tiny correction southward have huge cosequencesand plenty of time yet.

Share this post


Link to post
Share on other sites
4 minutes ago, Weather-history said:

Looking at Friday, if you look at the archive of famous snow events of the past, the uppers are not that impressive.

The famous snowstorm of March 1891 which buried the SW of England, the uppers don't look that special in the area that was badly hit. 

NOAA_1_1891030918_2.png

Look at the uppers for the famous ice and snowstorm of late January 1940. You wouldn't think you would get anything from that just on that chart.

NOAA_1_1940012706_2.png

Quite so weather history blizzard of 78 uppers were 0c to minus 2

Share this post


Link to post
Share on other sites

Let’s see where we are by tonight.

The actual block is expected to head further west but you only need a small correction in where the low goes to bring quite different conditions.

There’s been some corrections this morning from the outputs which have improved slightly from last night in terms of snow.

As long as you maintain that surface flow from the east even if the 850s become less cold it will still be cold at the surface .

Share this post


Link to post
Share on other sites

It's game over for the far south, pretty much unanimous agreement amongst the GFS and ECM ensemble suites for a fast warm up, I mean... anyone who can't see that in the GFS ensembles is in serious denial, people will say it's a 6 days away but we've seen once the GFS and ECM suites are onboard at this range they aren't often wrong.

 

Question for the more intelligent ones regarding the SSW, as it was a record reversal do you think to some extent that is what is shooting the coldest uppers straight through us at a vast rate of knots as the cold pool seems to move through us very fast, all things considered.

IMG_0382.PNG

Share this post


Link to post
Share on other sites

The January 1940 event certainly is one to keep in mind, though I think the uppers won't get nearly as warm this time round.Does give an idea WHY I actually think that the freezing rain solution is the most dangerous though. March 1891 looks synoptically very close to what we will have as well.

Anyway as has been said only going to require small corrections, anyone of the following will help the south:

1: Small south correction

2: Small east correction

3: Slower system giving it more time to mix out the milder air.

Share this post


Link to post
Share on other sites
3 minutes ago, Broadmayne blizzard said:

Quite so weather history blizzard of 78 uppers were 0c to minus 2

Time and time again, when looking at the archives of historical snow events, it's common to see that uppers were looking very "marginal".

Share this post


Link to post
Share on other sites
5 minutes ago, Weathizard said:

It's game over for the far south, pretty much unanimous agreement amongst the GFS and ECM ensemble suites for a fast warm up, I mean... anyone who can't see that in the GFS ensembles is in serious denial, people will say it's a 6 days away but we've seen once the GFS and ECM suites are onboard at this range they aren't often wrong.

 

Question for the more intelligent ones regarding the SSW, as it was a record reversal do you think to some extent that is what is shooting the coldest uppers straight through us at a vast rate of knots as the cold pool seems to move through us very fast, all things considered.

IMG_0382.PNG

Ok, no, friday is a long time away its not game over😂

Share this post


Link to post
Share on other sites
8 minutes ago, kold weather said:

The January 1940 event certainly is one to keep in mind, though I think the uppers won't get nearly as warm this time round.Does give an idea WHY I actually think that the freezing rain solution is the most dangerous though. March 1891 looks synoptically very close to what we will have as well.

Anyway as has been said only going to require small corrections, anyone of the following will help the south:

1: Small south correction

2: Small east correction

3: Slower system giving it more time to mix out the milder air.

ECM shows possible freezing rain on the back edge of the snow in places.

us_model-en_modez_2018022500_123_5595_155.png

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...