January 2019 Medium/Long Range Pattern Discussion

[Carvers Gap]

26 minutes ago, Holston_River_Rambler said:

The trend is your friend?

Yeah yeah, I know it's just the GEFS and probably won't get things just right, but I don't think ensemble means are meant to be diagnostic of specifics. They're more useful for trends. And that's what we need right now. We have all the specifics rain we need in the short term. Remembered Carver's suggested 5 day averages and the 6z GEFS's trends there look nice for now. Wait you might say, what about the 0z EPS? Yeah, it looks bad. But for now, I'm going with the Mets in the NE forum's idea that it has some problem with diurnal tropical convection and is doing a bad job with the MJO so far.  We'll see if the 12z EPS looks better. Well, better is a relative term give how it's dealing with the MJO. But I do see some similarities between this and the 12z (yesterday) EPS I posted earlier in this thread. Retrograding -NAO, attempt at a -AO, and slow retraction of the Pac jet. Maybe the GEFS isn't right, but if it is doing a better job dealing with the movement of the convection that is sustaining the Pac jet, maybe it's hints are useful.  

The GEFS has been decent this year.  It does IMHO have a cold bias at LR.  That said, it is also my opinion that the American model suite does pretty well w strat split stuff.    I think I remember someone stating that it also does pretty well w the MJO.  Biggest thing today is to watch trends at high latitude.   How/if the SSW effects the troposphere(nSSW or dSSW) is important.  Of equal importance is the MJO being decoupled from the El Nino.  There are some very good drivers out there for cold, they are not in sync.  It is possible that those drivers never sync...but there is also a possibility (maybe a stronger one) that some or all of those drivers sync and things flip.  I am waiting for the 12z run today before giving my final guess for January...

[Carvers Gap]

Well, that is interesting.  The SOI(source: Long Paddock) has again crashed.  That is a good sign if it can hold and continue to remain negative.  

 

[Carvers Gap]

Remember that Western Atlantic Ridge last February that basically ended winter.  It proceeded the strat split.  Take a look at what HM placed on Twitter.  Now, his focus is on a temporary ridge just to the west of the UK that surges poleward, but take a look at eastern NA.  Anyway, I think last winter's version of the UK ridge was the WAR.  Even though this year did not have that mega-ridge here, we still had quite the ridge.  Something to file away.  From what I have read, I do think this split will be different this year.  He also has some comments on how this might induce blocking in the NAO region if you look at that thread.  

 

 

[Carvers Gap]

FWIW, I do expect the Weeklies to flip warm tonight...the EPS did not look good this AM.  In the off chance that the Euro Weeklies are cold after being derived from a warm run, that means that model is really seeing something that signals cold.  As a friend noted, maybe they were just too quick on Thursday?

[AMZ8990]

11 minutes ago, Carvers Gap said:

FWIW, I do expect the Weeklies to flip warm tonight...the EPS did not look good this AM.  In the off chance that the Euro Weeklies are cold after being derived from a warm run, that means that model is really seeing something that signals cold.  As a friend noted, maybe they were just too quick on Thursday?

Kind of confusing isn’t it! LOL

[Carvers Gap]

Just now, AMZ8990 said:

Kind of confusing isn’t it! LOL

Honestly, it drives some folks crazy.  I kind of like the uncertainty.  And that Thursday Euro Weeklies run appears to be a bit of an outlier.  However, it is not uncommon for LR modeling to be too fast as noted by a friend.  That said, it has been pushing back cold for 2-3 weeks...so not sure that applies.  At some point, a model is just incorrect.  Of note, the Weeklies are fairly sensitive to the run that they are derived from.  If they still go cold(tonight) after being derived from a warm run the morning, then we may have something.  If they flip warm, that is probably to be expected.  Again...w the current SSW(and the unknown of if/when it affects the troposphere), the SOI that has been positive, the anomalous MJO amplitude, and the subsequent non-coupling(is that even a wx term?!) of the Nino state to the MJO/SOI...I am not sure any wx model on the planet can juggle those.  Now, if the Euro nails this pattern...that will be incredibly, incredibly impressive given the number of variables that are unknown.  It would be understandable if all models whiff on what actually becomes reality.  That said, this strat split was again nailed at LR by maybe the CFS(?).  That type of performance was unrealistic when I started doing this as a hobby 20 years ago.  So, we have come a very long way in a very short amount of time in terms of atmospheric modeling.  Again, how amazing is it to see those 3-D polar vortex splits(into three no less).  

[Carvers Gap]

25 minutes ago, AMZ8990 said:

Kind of confusing isn’t it! LOL

Also, folks have been discussing gradient issues.  Typhoon Tip recently mentioned it.  Normally we have an El Nino that is surrounded by cooler water.  That gradient produces the expected reactions(wx pattern) over NA.  Right now, the Pacific basin is fairly warm and that is reducing the gradient.  (Also, I "think" there is some cold water now appearing just off the coast of western equatorial South America....that is off the top of my head). But the lack of gradient between the Nino state and the typically cooler waters around it might be creating a brand new analog w original consequences over the northern hemisphere.  Here is another crazy thing....There is a strat split over the Southern Hemisphere I think.     

Addendum:  Temperature gradients produce pressure gradients.  In turn, those create wind currents which move air from areas of high pressure to areas of low pressure.  That is what drives the weather on our planet.   We are used to predicting the weather based on certain gradients and weather patterns...if those change, we are flying blind until we can build/improve models to account for those new patterns.  The physics obviously don't change, but analogs might be less useful if the previously known and used gradients are different.

[AMZ8990]

39 minutes ago, Carvers Gap said:

Also, folks have been discussing gradient issues.  Typhoon Tip recently mentioned it.  Normally we have an El Nino that is surrounded by cooler water.  That gradient produces the expected reactions(wx pattern) over NA.  Right now, the Pacific basin is fairly warm and that is reducing the gradient.  (Also, I "think" there is some cold water now appearing just off the coast of western equatorial South America....that is off the top of my head). But the lack of gradient between the Nino state and the typically cooler waters around it might be creating a brand new analog w original consequences over the northern hemisphere.  Here is another crazy thing....There is a strat split over the Southern Hemisphere I think.     

Addendum:  Temperature gradients produce pressure gradients.  In turn, those create wind currents which move air from areas of high pressure to areas of low pressure.  That is what drives the weather on our planet.   We are used to predicting the weather based on certain gradients and weather patterns...if those change, we are flying blind until we can build/improve models to account for those new patterns.  The physics obviously don't change, but analogs might be less useful if the previously known and used gradients are different.

  Great post CG, thank you.  One question- don’t the cooler waters off of western South America usually run in line with Modoki El Niño’s though?  Or is this just a case of to little to late to affect nino in that way. 

[Carvers Gap]

1 hour ago, AMZ8990 said:

  Great post CG, thank you.  One question- don’t the cooler waters off of western South America usually run in line with Modoki El Niño’s though?  Or is this just a case of to little to late to affect nino in that way. 

I think that is correct.   Just saying that is one more piece to the puzzle that models have to juggle.  Seems like the water there is colder than usual....but I read that somewhere and just filed it away for a later date.  Can't remember where I read that....maybe Twitter(and I don't Twitter much...just some folks who I regard as very good mets, interesting mets, and/or climate folks.  Only follow like 25 people right now.).

[Holston_River_Rambler]

NASA GOES model now doing something even weirder with the strat pv and trying to recombine the two larger parts of the split, but over North America: https://stratobserve.com/tht_pvstr_maps (Need to look at 800k (~10hPa) and above to see this) 12z GFS looks like it is trying to do something similar.

If you have some time, click through all the levels from 1500k all the way down to 400k. Pretty neat to see how the strat vort splits different ways at different levels. Below 800k the N American part seems less potent. 

 

[Carvers Gap]

2 minutes ago, Holston_River_Rambler said:

NASA GOES model now doing something even weirder with the strat pv and trying to recombine the two larger parts of the split, but over North America: https://stratobserve.com/tht_pvstr_maps (Need to look at 800k (~10hPa) and above to see this) 12z GFS looks like it is trying to do something similar.

If you have some time, click through all the levels from 1500k all the way down to 400k. Pretty neat to see how the strat vort splits different ways at different levels. Below 800k the N American part seems less potent. 

 

Yeah, I noticed the recombining this morning.  It would be nice if over NA...if it tightens back up over the pole that is a big problem....even if it tightens up over northern NA, that could still bottle up the cold.  I still think this thing is pretty unpredictable.  We need it beat-up and not uniform.

[AMZ8990]

What do we think is going to happen in regards to the MJO.  The map I just looked  seems like it’s doing circles in phase 5 up to the 23rd but it was heading towards phase 6 at the end of the run on the 23rd.   Anybody know if it’s still heading towards phase 6 at the present time?

[Holston_River_Rambler]

3 minutes ago, AMZ8990 said:

Anybody know if it’s still heading towards phase 6 at the present time?

It is.

[AMZ8990]

Just now, Holston_River_Rambler said:

It is.

  Thanks HRR!

[Holston_River_Rambler]

I think that's partly why the SOI is falling. There's been a tropical cyclone near N. Australia just chillin out doing circles, so the MSLP at Darwin is lower in response to that. Looking at the negative SOIs the closer the observed pressures are at Darwin and Tahiti, the lower the SOI. So if Tahiti is living the dream under high pressure and Darwin is getting cyclon'd, I think that usually reflects not only the MJO in a bad place and contributing to the Pac jet, but the SOI is going to be higher too. Once that cyclone scoots out (and it looks like it is going to take its time) will be interesting to see where the SOI heads. 

[Holston_River_Rambler]

@AMZ8990 Here is a link that seems to update pretty regularly that lets you look at BOMM, GEFS, Euro, JMA, and I think Canadian MJO forecast for easy comparison.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/clivar_wh.shtml#for 

You just have to mouse over the model to see it. For some reason some of the models on the page you can mouse over don't work, but most of them do. 

We can all hope and dream the CFS has it right! I know I do!

[tnweathernut]

2 minutes ago, Holston_River_Rambler said:

@AMZ8990 Here is a link that seems to update pretty regularly that lets you look at BOMM, GEFS, Euro, and I think Canadian MJO forecast for easy comparison.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/clivar_wh.shtml#for 

Thanks for posting this.  What sticks out (at least to me) is the very poor MJO handling in the last several days from the European modeling.  Pretty crazy how wrong it has been at VERY short (1-2 day) lead times.    It might lend credence to the EPS being dead wrong about our never ending spring(ish) weather.   We will know soon enough.

[AMZ8990]

10 minutes ago, Holston_River_Rambler said:

@AMZ8990 Here is a link that seems to update pretty regularly that lets you look at BOMM, GEFS, Euro, JMA, and I think Canadian MJO forecast for easy comparison.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/clivar_wh.shtml#for 

You just have to mouse over the model to see it. For some reason some of the models on the page you can mouse over don't work, but most of them do. 

We can all hope and dream the CFS has it right! I know I do!

Thanks, I’m with you too after looking at it.  CFS camp all the way!!!

[Holston_River_Rambler]

Speaking of phase 6 @AMZ8990

Just read in the MA and NE forum that Isotherm claims the MJO is already in phase 6 and showing no signs of weakening. Some of you may know this already, but for those who don't the plots at the link I posted are called RMM diagrams. But there are other ways to determine the phase. 

Hope he doesn't mind the quote, and hope I'm not misrepresenting, but seems pertinent to our MJO discussion:

 

[Carvers Gap]

As we near record highs for TYS and TRI...check out in the observation thread when TYS set their record high for that date. 

[AMZ8990]

1 hour ago, Holston_River_Rambler said:

Speaking of phase 6 @AMZ8990

Just read in the MA and NE forum that Isotherm claims the MJO is already in phase 6 and showing no signs of weakening. Some of you may know this already, but for those who don't the plots at the link I posted are called RMM diagrams. But there are other ways to determine the phase. 

Hope he doesn't mind the quote, and hope I'm not misrepresenting, but seems pertinent to our MJO discussion:

 

  Interesting, definitely makes one wonder what could come once we get around the 10th of January and beyond.

[Carvers Gap]

All right....final call for January. Not even gonna look at the Weeklies...they are probably not gonna be pretty.   My seasonal forecast is slightly AN for December, normalish for Jan, and BN for Feb.

Right now this is a GEFS/GEPS vs EPS battle in the LR.  They are basically the exactly opposite w the EPS having a trough in the West and ridge in the East w the ridge maybe lifting out late... if extrapolated(basically a real crap show if you like winter...let's be honest....it is ugly...LOL).  The GEFS/GEPS is a weak trough in eastern NA w nice blocking over the top on the GEFS.  No model has sustained, signifiant cold air over the EC of the Lower 48...If the GEFS is to be believed, the cold lurks in Canada.  Basically, I think modeling is juggling so much stuff(see earlier posts), that I am going with climatology for the back half of the month and ensembles for the first half.

So, with all of that in mind...I am betting on a pattern flip.  When this potential happens makes the month very difficult to forecast.  So here is my best shot, and it may just be flat-out wrong in the end.  

January Temps

Week 1: AN

Week 2: much AN

Week 3: (transition week w the flip late in the week) normal to slightly AN

Week 4: BN (might be well below)

Overall month: Slightly AN with the assumption that the last 1/3 of January goes stone cold and erases significant warmth on the front end.  Right now that is a hunch with not a lot of model support.  Basically going to ride Nino climatology and bet that the SSW does its dirty work in terms of blocking.  Also, going to ride with the work that John has done regarding the November/January cold relationship.  I don't have to do this for a living so I can gamble a bit.   But I am going to bet the flip.

January Snowfall

This is always a total crapshoot.  I am going to go normal w a big storm to end the month and begin the new pattern.  I am still bullish about February w slightly AN.

Final note:  I also see a path to where this winter could be AN the rest of the way.  94-95 is a decent analog.  I also remember 89-90(Nina?) and I can't discount it since some indices such as the SOI have long term trends w Nina climatology.  So when in doubt...I am riding w weak Nino climatology which is a backloaded winter.  

[Icy Hot]

1 hour ago, Carvers Gap said:

All right....final call for January. Not even gonna look at the Weeklies...they are probably not gonna be pretty.   My seasonal forecast is slightly AN for December, normalish for Jan, and BN for Feb.

Right now this is a GEFS/GEPS vs EPS battle in the LR.  They are basically the exactly opposite w the EPS having a trough in the West and ridge in the East w the ridge maybe lifting out late... if extrapolated(basically a real crap show if you like winter...let's be honest....it is ugly...LOL).  The GEFS/GEPS is a weak trough in eastern NA w nice blocking over the top on the GEFS.  No model has sustained, signifiant cold air over the EC of the Lower 48...If the GEFS is to be believed, the cold lurks in Canada.  Basically, I think modeling is juggling so much stuff(see earlier posts), that I am going with climatology for the back half of the month and ensembles for the first half.

So, with all of that in mind...I am betting on a pattern flip.  When this potential happens makes the month very difficult to forecast.  So here is my best shot, and it may just be flat-out wrong in the end.  

January Temps

Week 1: AN

Week 2: much AN

Week 3: (transition week w the flip late in the week) normal to slightly AN

Week 4: BN (might be well below)

Overall month: Slightly AN with the assumption that the last 1/3 of January goes stone cold and erases significant warmth on the front end.  Right now that is a hunch with not a lot of model support.  Basically going to ride Nino climatology and bet that the SSW does its dirty work in terms of blocking.  Also, going to ride with the work that John has done regarding the November/January cold relationship.  I don't have to do this for a living so I can gamble a bit.   But I am going to bet the flip.

January Snowfall

This is always a total crapshoot.  I am going to go normal w a big storm to end the month and begin the new pattern.  I am still bullish about February w slightly AN.

Final note:  I also see a path to where this winter could be AN the rest of the way.  94-95 is a decent analog.  I also remember 89-90(Nina?) and I can't discount it since some indices such as the SOI have long term trends w Nina climatology.  So when in doubt...I am riding w weak Nino climatology which is a backloaded winter.  

So basically, we will know the weather when we stick our heads out the window.

[Carvers Gap]

23 minutes ago, Icy Hot said:

So basically, we will know the weather when we stick our heads out the window.

LOL.  It might be one of those months with so much uncertainty .  Hopefully, we transition back to winter later this month.  For now, we can just ride with the car windows down.  

[Carvers Gap]

Hot off the press...Euro Weeklies (hindcast has run...below is how the 850s/500 look...2m temps not out yet). This is just 850 stuff and am interested to see what 2m temps look like:

Week 1:  Much AN

Week 2:  Much AN

Week 3:  AN but a transition week

Week 4:  BN

Week. 5: BN

Week 6:  Much BN

1/2 of week 7:  Much BN

Of note, if you look at the EPS on both runs today, the Euro brings a trough into the West very late in the run.  On the Weeklies it builds the cold eastward from that trough with the trough eventually progressing and holding in the East.  Normally, I would be pretty happy to see a run like that.  It looks good.  What we do know is that the Weeklies have consistently pushed back this switch to cold for the past several weeks.  What is good about this run, it didn't flip cold.  What is bad, it took expected baby steps away from a great look last Thursday.  If correct(and that is a BIG if given past performance), the month would finish AN.  Overall, the progression made a bit more sense this run.  The run last Thursday never had support from the EPS.

FTR: I put my January thoughts in writing before the Euro Weeklies ran.

**Update:  The non-hindcast Weeklies are basically the same set-up. Again, normally I would be enthused.  It is basically a retread of the run last Monday w some slight differences.  And I re-iterate w so much going on right now in terms of undefined variables....I wouldn't trust a model past ten days right now.  So, understand this....is me bringing you information.  This is not a forecast.****

[Holston_River_Rambler]

For any who are still interested: 

 

Some may prefer this ever popular model at this point:

https://imgur.com/gallery/k9Ex3 

Not saying I would blame you. 

[Holston_River_Rambler]

There must have been some icy members in the overall run past day 15. One individual member had a section 9+ inches into the Gulf of Mexico! That was certainly a single outlier, but others pushed some nice storms even south of us.

@Carvers Gap the specific member for the gulf snow was member 27. Could have just been a weird anomalous event, but you'd think there would have to be some good suppression to give the Gulf SE of Marsh Island, LA 9 inches! 

[Carvers Gap]

3 minutes ago, Holston_River_Rambler said:

There must have been some icy members in the overall run past day 15. One individual member had a section 9+ inches into the Gulf of Mexico! That was certainly a single outlier, but others pushed some nice storms even south of us. 

I will give it a look.  I can't see individual maps.  Plus the run isn't finished yet on WxBell.  The progression on this looks reasonable.  But again, I caution...with so much stuff going on right now, I doubt we have seen the last flip or even the last two flips.  I didn't consider tonight's run a flip though.

[Carvers Gap]

Definitely a block look after mid-month.  It is about Jan 20 where the -NAO/-AO sync.  Green line is the mean.  Dots are the control.  Could be Much moving the football another week or it could fit Nino climatology like a glove.  Here are there teleconnections...

 

[Carvers Gap]

The 46 day snow mean stayed generally the same compared to Thursday and might have increased in NE TN.  The control was pretty much barren.  But after looking at the AM run, I can see why it was barren!  LOL.  Anyway everyone, take it with a huge grain of salt.  While not expecting much for a couple of weeks, I still think patience will be rewarded....and Happy New Year to all!