Cold hunt - models and chat

[Summer Sun]

Just now, Blizzardof82 said:

GFSP says hold my beer, we are not done with Winter just yet

Not a lot of support for it either (yellow and black line)

[Nick F]

Extended 00z EPS ensemble mean shows quite a strong -ve height anomaly / trough over Azores, especially days 11-12, while downstream stronger ridging building N and NW across the NE Atlantic. However, suggests a fine line between mild southerlies and a cold continental flow, depending on where surface high pressure sets up - which the mean will blend out the different options.

[IDO]

4 minutes ago, That ECM said:

End of feb is 17 days away. It might not end up cold but it’s 17 days away

The NAO Index for January came in at +0.59 (NOAA CPC)

The NAO has been: Negative in 2 of the last 16 months

Negative in 3 of the last 32 Dec-Mar winter months

Negative in 1 of the last 24 Dec-Feb winter months

Positive the last 8 Decembers

Positive the last 8 Januarys

source: @griteater

That is what we are fighting so the default is likely to be not cold for the UK, and we have to look for background signals that will flip that. I cannot see it ATM, especially with the MJO now stalling in Phase 7, and that is assuming no interference, unlikely based on this Winter's performance.

We can hope, but the likelihood is clearly unfavorable.

[Chris101]

1 hour ago, mb018538 said:

I guess a stopped clock is right twice a day....

00z runs holding zero promise in my eyes. Once this weeks mildness is blown away it looks like a return to wind and rain. Nothing to whet the appetite in this busted flush of a winter.

Even the analogies in here make no sense

[Blizzardof82]

We can dream GFSP 00z ends like this

[winterof79]

27 minutes ago, Summer Sun said:

Not a lot of support for it either (yellow and black line)

Mike said it runs at high res throughout?

[frosty ground]

16 minutes ago, IDO said:

The NAO Index for January came in at +0.59 (NOAA CPC)

The NAO has been: Negative in 2 of the last 16 months

Negative in 3 of the last 32 Dec-Mar winter months

Negative in 1 of the last 24 Dec-Feb winter months

Positive the last 8 Decembers

Positive the last 8 Januarys

source: @griteater

That is what we are fighting so the default is likely to be not cold for the UK, and we have to look for background signals that will flip that. I cannot see it ATM, especially with the MJO now stalling in Phase 7, and that is assuming no interference, unlikely based on this Winter's performance.

We can hope, but the likelihood is clearly unfavorable.

This post makes little sense, what has the measured NAO in December got to do with February? Are you pointing out a link?

[feb1991blizzard]

2 minutes ago, winterof79 said:

Mike said it runs at high res throughout?

It seems that way to me anyway, you can always tell by how long it takes to come out, and it stalls just as much at the end of the run as at the start, where as the op after 240 just race out, as do the ensembles.

[Summer Sun]

7 minutes ago, winterof79 said:

Mike said it runs at high res throughout?

Not sure but this version of GFS P is 0.25 high res but only runs to D10

https://www.meteociel.fr/modeles/gfs-para/pression/3h.htm

"These maps are based on raw data from the US GFS parallèle (Global Forecast System) High Resolution (0.25deg) model"

Edited February 11, 2019 by Summer Sun

[frosty ground]

2 minutes ago, Summer Sun said:

Not sure but this version of GFS P is 0.25 high res but only runs to D10

https://www.meteociel.fr/modeles/gfs-para/pression/3h.htm

"These maps are based on raw data from the US GFS (Global Forecast System) High Resolution (0.25deg) model"

Isn't that just a copy of the original GFS layout. 

[feb1991blizzard]

Yes, i don't think the grid is any different.

[mountain shadow]

34 minutes ago, IDO said:

The NAO Index for January came in at +0.59 (NOAA CPC)

The NAO has been: Negative in 2 of the last 16 months

Negative in 3 of the last 32 Dec-Mar winter months

Negative in 1 of the last 24 Dec-Feb winter months

Positive the last 8 Decembers

Positive the last 8 Januarys

source: @griteater

That is what we are fighting so the default is likely to be not cold for the UK, and we have to look for background signals that will flip that. I cannot see it ATM, especially with the MJO now stalling in Phase 7, and that is assuming no interference, unlikely based on this Winter's performance.

We can hope, but the likelihood is clearly unfavorable.

A very sobering post. 

I don't think the MJO is stalling in Phase 7 though, it is going to move into 8 but at far less amplitude as they were predicting last week. 

That for me is why my towel is thrown in for the Winter, see y'all next Winter.

[IDO]

8 minutes ago, frosty ground said:

This post makes little sense, what has the measured NAO in December got to do with February? Are you pointing out a link?

That is the background we work within, an NAO predominantly opposed to sustained cold. To get a cold Feb we need a trigger to break the climate trend, last March was from an SSW. 

It is, therefore, reasonable to assume no sustained cold in Feb without a variable bucking that trend; just saying there are another 17 days, is not IMO important without the background signals to back up a flip to cold?

Bearing in mind 15c is forecast later this week I really fail to see this Feb being anything but above the CET historical mean. Do you think otherwise and if so, why?

[feb1991blizzard]

3 minutes ago, IDO said:

That is the background we work within, an NAO predominantly opposed to sustained cold. To get a cold Feb we need a trigger to break the climate trend, last March was from an SSW. 

It is, therefore, reasonable to assume no sustained cold in Feb without a variable bucking that trend; just saying there are another 17 days, is not IMO important without the background signals to back up a flip to cold?

Bearing in mind 15c is forecast later this week I really fail to see this Feb being anything but above the CET historical mean. Do you think otherwise and if so, why?

Yes, that is a 100% guarantee now.

[Summer Sun]

A settled 10-days ahead looking at the average pressure slightly lower in Scotland but no washout by any means. Mild as a result widely across Europe.

[Mike Poole]

32 minutes ago, winterof79 said:

Mike said it runs at high res throughout?

Yes, FV3 does run at high resolution throughout.  This explains:

https://www.emc.ncep.noaa.gov/gmb/wx24fy/doc/CCB_FV3GFS_24sept2018_v4.pdf

See slide 4.

When it takes over it will run slower than current GFS, see slide 22.

And lots of other interesting stuff about the model too...

[Purga]

At least GFSP keeps a sense of humour amidst all the mild onslaught.

BTW it looks like the Beast wants to come back for his birthday! LOL!

Edited February 11, 2019 by Purga

[Timmytour]

58 minutes ago, Summer Sun said:

Not a lot of support for it either (yellow and black line)

In such situations we do not refer to the run as being either an outlier or without support, instead we hail it as a trendsetter!

[booferking]

31 minutes ago, frosty ground said:

This post makes little sense, what has the measured NAO in December got to do with February? Are you pointing out a link?

It makes perfect sense where i sit not even great background signals for a -NAO can flip it.

[TEITS]

5 minutes ago, IDO said:

 To get a cold Feb we need a trigger to break the climate trend, last March was from an SSW. 

 

Was it though?

Clearly this winter has shown that just one variable i.e SSW isn't the sole reason for a cold spell in the UK. The bitter E,ly last winter would of been caused by other variables being favourable.

I shall repeat what I said at the beginning of this winter and have said for several years now. The reason why we cannot forecast using Teleconnections is because we do not fully understand them and more importantly how they interact with each other. You then have the added complication of the UK being a tiny Island.

Obviously this doesn't mean members should give up trying. However if members want a more stress free model viewing next winter then they should take background signals with a pinch of salt until this promise appears at +144. I started this winter with a new approach of only viewing to +144 with a glancing look at the ECM to +240. However I admit the temptation of looking at GFS +384 was too much when promising charts failed to appear within the reliable timeframe.

[TEITS]

3 minutes ago, booferking said:

It makes perfect sense where i sit not even great background signals for a -NAO can flip it.

Always much more likely to see a +NAO in Dec compared to Feb. Also I can think of many occasions when the NAO has been positive in Dec but negative in Feb.

If you look back then historically UK cold spells have always been more likely after Xmas than before. The Likes of Dec 1981, 2009,2010 were very unusual.

[kold weather]

Pretty clear we are in a decent +be NAO pattern for now. As Nick said we may swing a technical -ve spell if we were to see an upper low dives into the Atlantic but a long way off.

Looking well above average this week, and a far better chance of a top 10 mildest Feb's then a below average Feb...I'd say probably equal odds for a record breaking Feb than a below average one. I don't think either will happen, But who knows!

Also possibility of a daily record of two being broken this week.

Edited February 11, 2019 by kold weather

[frosty ground]

23 minutes ago, IDO said:

That is the background we work within, an NAO predominantly opposed to sustained cold. To get a cold Feb we need a trigger to break the climate trend, last March was from an SSW. 

It is, therefore, reasonable to assume no sustained cold in Feb without a variable bucking that trend; just saying there are another 17 days, is not IMO important without the background signals to back up a flip to cold?

Bearing in mind 15c is forecast later this week I really fail to see this Feb being anything but above the CET historical mean. Do you think otherwise and if so, why?

Again what has the measured value of Decembers NAO got to do with February?

Sustained cold in any winter month is against climate norm for the UK but that has little to do with past NAO readings taken over 45 days ago.

We had a SWW and it failed to deliver which as been mention a billion times can happen in 1 in 3 events, that had nothing to do with the NAO reading from December.

We can have one cold week and still maintain an above average CET average for the month, the temps this week will have no bearing on that, as it stands there is not much sign of a cold outbreak at the moment but there is nothing to say there won't be any changes either.

[frosty ground]

14 minutes ago, booferking said:

It makes perfect sense where i sit not even great background signals for a -NAO can flip it.

Flip what?

[frosty ground]

20 minutes ago, Timmytour said:

In such situations we do not refer to the run as being either an outlier or without support, instead we hail it as a trendsetter!

We can say it's an outlier because it has support, so it would be trendsetters