[Model Output Discussion - Spring Has Sprung]

Blimey - over the past couple of weeks I've been following the models quite loosely, just checking the latest GFS ensemble when I remember, and today I saw more agreement on something interesting next week.  Only then did I peruse the other models...  Goodness the latest GEM is some eye candy. 

I'm back baby! 

[Moans, ramps and banter]

1 hour ago, North Easterly Breeze said:

Had to laugh at the radar this morning, almost taking the you know what out of the south as it covers Belgium in snow.

You think that's bad.  Apparently it's snowing here.

[Model Output Discussion - Colder but how cold and for how long?]

3 minutes ago, nick sussex said:

The models just refuse to really break through the snow shield with these coastal teases .

At this timeframe there’s still room for changes but we do need the 12 hrs runs to collectively push things north .

 

There is still a bump of 'New Snow' showing for Horsham from the GEFS, but it's shrunk a little since yesterday

 

[Model Output Discussion - Colder but how cold and for how long?]

6 minutes ago, Mcconnor8 said:

Arome gives hope for the far South East

There has to be a positive (from a winter perspective) of living on the south coast.   

[Model Output Discussion - Colder but how cold and for how long?]

4 minutes ago, SilverWolf said:

Jeez, this is proving to be a little stressful now..

I'd settle for that 

 

 

[Model Output Discussion - Colder but how cold and for how long?]

Just now, seabreeze86 said:

GFS ensembles are interesting at 96hrs for the first time they are many that go below -12hpa some as low as -16hpa. These were not there earlier and at such a early timescale 

Agreed.  As said above, on the locations I'm monitoring, the average has never been so low (-8.9c) as it is now 

[Model Output Discussion - Colder but how cold and for how long?]

3 minutes ago, jright35 said:

 

Not completely dry on the ensemble, admittedly for mid Sussex.  This is New Snow 

P23 is the light blue line  

[Model Output Discussion - Colder but how cold and for how long?]

Crazy cold on the ensemble by the 16th. Average 850hpa temp is -8.9c and some go as low as -14c.

[Model Output Discussion - Colder but how cold and for how long?]

19 minutes ago, Bricriu said:

 

 

I am sure someone  will mention ensembles showing otherwise and that there is no trend, but that's two GFS runs, along with the ECM and EC46 showing a more westerly influence for the final week of January.  Also John Holmes indicated this might happen too. On a more positive note any westerly influence  will hopefully be brief. I don't think I could take another lengthy Zonal period.

Spot the outlier / trend setter*

 

* delete as applicable 

[Model Output Discussion - Colder but how cold and for how long?]

Just now, Drifter said:

For us? Rain. 

Feel like testing the sweat filter!

Why? Are you a royal prince?

[Model Output Discussion - Colder but how cold and for how long?]

1 minute ago, RainAllNight said:

I don't know what this means 

Snow north of the M4?

 

 

[Model Output Discussion - Colder but how cold and for how long?]

Just now, Jason M said:

Yes, but control and Opp running together at day 8 cannot be ignored.

True, but they both ran cold earlier, so take you pick.  Until the ensemble converges we're going to be flip-flopping.  At least the majority have 850pha temps down to close to -10c by 15th; in fact the average for the cluster is -6.5C, which is about as low as it's been shown recently.  

[Model Output Discussion - Colder but how cold and for how long?]

6 minutes ago, Bricriu said:

How can the GFS change so much from one run to the next. This morning it looked good for extending the cold but now it looks like it may not last at all. I appreciate some could  get a dumping before  all that happens 

There's the reason, a 17C range - with the GFS Op right at the top of the spread.  

[Model Output Discussion - Colder but how cold and for how long?]

12 minutes ago, Continental Climate said:

Just my opinion of course I think it will travel south through the channel and will be all snow for our South Coast contingent.  

May I quote you on that?

Oh I have

[Model Output Discussion - Colder but how cold and for how long?]

Just now, northwestsnow said:

I've not seen the mood so high for a long time on NW!!

Let's hope the upgrades continue tonight  

Or we'll see toys lobbed everywhere 

[Model Output Discussion - Colder but how cold and for how long?]

Just now, Mcconnor8 said:

ECM 06z Control is looking so much better than the 0z did, will update with pics when it finishes running!

It is very much so.  Clean.

[Model Output Discussion - Colder but how cold and for how long?]

2 minutes ago, Mcconnor8 said:

Meteociel - Cartes Ensemble CEP/ECMWF ENS

WWW.METEOCIEL.FR

---

meteociel propose des rubriques météo temps réel, forums, modeles...

ECM run that goes out to +144 Hours with an ensemble set as well, has an 18z run as well that is the same.

The Op run is here I think 

 

WWW.METEOCIEL.FR

---

Meteociel propose le modèle deterministe de ECMWF CEP en Open-Data avec une résolution de 0.4°

 

[Model Output Discussion - Colder but how cold and for how long?]

12 minutes ago, sheikhy said:

Ecm 06z looking juicy at just 90 hours!better block and colder air further south!!!

Hopefully this GIF shows the difference.  A wedge of 1025hpa has been lost to our south 

[Model Output Discussion - Colder but how cold and for how long?]

I'm not going to post individual ensemble members (that's some else's job) but there are some very very interesting ways to get cold and widespread snow in the GFS 6z ensemble.  

Nice to see.   

[Model Output Discussion - Colder but how cold and for how long?]

8 minutes ago, kold weather said:

It's a total mess on the ensembles even on the macro level to be honest, complicated by the fact that relatively minor adjustments will make the difference between a 2 week exceptional spell and a rain event with a little snow for Scotland and SW airflow further beyond.

I think we can only hope it falls favourably for is, it's been a little while since we've really lucked in.

Yes. As an example. At day 4 we have a 10c spread at the 850hpa temp level, and over 15c difference a week out.  So, all to play for really! 

This is for Sussex, as we're at the southern extreme in terms of possible outcomes. 

[Model Output Discussion - Into 2024]

9 minutes ago, Hammer50 said:

A week is a long time in the weather world just have to wait and see pray the line is just into France for us southerners .

Yep. The odds are stacked against it, but other than a proper Easterly were hardly in the best locations for cold and snow.

I've had snow this winter already.

 

[Model Output Discussion - Into 2024]

9 minutes ago, SussexSnow said:

 

I think at the resolution of the Op run the GFS data point for Worthing includes part of the English channel, so the T2M is often moderated this way. 

To show the difference, this is for Horsham, the 850hpa temps are pretty much identical, but the T2M are more in line with the 'pack', although still quite high within the overall ensemble. 

[Model Output Discussion - Into 2024]

3 minutes ago, northwestsnow said:

WTF went on with the op it was Basil from the starting pistol ..

 

Just now, snowblind said:

That doesn't look as bad as I was expecting from reading some of the other posts.

Temps generally below 5 for your south coast location, raising slightly towards the end, with the op above the mean for the duration.

Let's hope for a better op this afternoon.

I think at the resolution of the Op run the GFS data point for Worthing includes part of the English channel, so the T2M is often moderated this way. 

[Model Output Discussion - Into 2024]

The GFS ensemble T2M chart shows a little uncertainty. 

 

[Model Output Discussion - Into 2024]

25 minutes ago, Purga said:

There'll be more than a few Swearing AGAIN*d off southerners if this verifies.

We're so used to it by now.