January 2024 Weather Discussion

[tron777]

Time to get the January thread going! We will begin the month on NYD with a possible clipper system dropping thru the trough. A few rain and snow showers possible but not really a big deal. Highs for the first week of January look to be seasonal in the Upper 30s to the middle 40s and lows in the 20s to the lower 30s. I thought that maybe around the 2nd or 3rd, we would have a system to talk about, a southern slider, but as of this post, the moisture looks to stay south of our local area.

Then, around the 7th, another STJ wave comes up from the SW, but as of now, this maybe all rain due to the lack of cold air. Then from the 10-12th, the pattern and storm evolution gets very murky so I'll stop there. If we get a big cutter, we should be able to pull down some colder air for a more sustainable wintry pattern. But we are not sure as of now how that storm, or multiple storms, will evolve. I do like the baroclinic boundary that has been showing up on some guidance but it's way too early to get too specific this far out in time. Hoping from mid January on, winter gets rocking. The potential for winter to be good is still there. The first week or so of the month... not so much unless something changes on the modeling between now and then.

Bgoney made a great post about the Aleutian Low. It is NOT in the correct location is the problem. It is too close to mainland Alaska. It wipes out any attempt at a sustainable -EPO or ridging over Alaska. If the current ensemble guidance is correct, that changes. The low retrogrades to the west, towards the tip of the Aleutians, and that is the classic spot that you want it to be in to get a nice sustainable ridge over Alaska to drain the arctic air southward from Siberia, into Canada, and eventually into the CONUS. It is the usual most winters lately, to see the cold dump out West first and then slowly bleed east. We see that during Week 1 of January. After the 10th, if the guidance is correct, we get the nice -EPO and a nice -NAO. The PNA is negative which is fine as long as you have the aforementioned blocking. The -PNA keeps the storminess coming but you don't get the SE ridge either as long as the EPO works in conjunction with the -NAO.

I know this winter has been frustrating. A warm December was called for by everyone, but I did not think it would be this warm. Trev did the best with regards to temps and lack of snowfall. If I recall, he even called for an inch or less of snow. Right on the money if you ask me. Great job Trev! Hopefully things turn soon! I did call for mid January and February to be our best window for winter so hopefully, I don't miss that call so I can get a B winter outlook grade instead of a C or D. So far Trev, you get an A thru the 1st month. Giving myself a B for December since I was not warm enough.

[tron777]

12Z EPS still looking good in the longer term.

EPS1.png

EPS2.png

[Bgoney]

New month and a PV update , looks like it stays weak and displaced a bit for most of Jan, atm . Fine by me, it has pretty much been in that state for much of December and don’t feel like that’s been the problem .


Polar vortex status

The SPV is currently weaker than ERA5 average
and is forecasted to remain weaker than average (according to GEFS-mean)
3 of 31 members have stronger vortex than average at the last forecast step (2024-01-12 12:00:00)

The SSW probability in GEFS is: 10%

The zonal mean zonal wind at 10 hPa 60N is today (GFS analysis): 29.4 m/s
Weakest zonal wind at 10 hPa 60N in ERA5 record for todays date is: 3.2 m/s 2001
Strongest zonal wind at 10 hPa 60N in ERA5 record for todays date is: 61.3 m/s 1988

[tron777]

I agree. The problem has been that the cold air has been trapped on the other side of the globe and no mechanism to get it to fill up our side. That should change in the next 10 days or so per longer term guidance if it is correct. We just don't yet know this far away. The pattern is changing from well above normal to more seasonal temps so that is step 1. Hopefully the next step after that is something akin to the above EPS images.

[Bgoney]

I agree. The problem has been that the cold air has been trapped on the other side of the globe and no mechanism to get it to fill up our side. That should change in the next 10 days or so per longer term guidance if it is correct. We just don't yet know this far away. The pattern is changing from well above normal to more seasonal temps so that is step 1. Hopefully the next step after that is something akin to the above EPS images.

I was just going to post the same thing. lol, Got to get the PAC blocked up for Canada

[tron777]

I agree. The problem has been that the cold air has been trapped on the other side of the globe and no mechanism to get it to fill up our side. That should change in the next 10 days or so per longer term guidance if it is correct. We just don't yet know this far away. The pattern is changing from well above normal to more seasonal temps so that is step 1. Hopefully the next step after that is something akin to the above EPS images.

I was just going to post the same thing. lol, Got to get the PAC blocked up for Canada

Exactly! Once that happens, the Pacific jet will slow down. Then the real fun can begin to go along with the active subtropical jet. Fingers crossed!

[Bgoney]

Not much change overnight. First week still featuring multiple southern stream systems. Going to need a northern stream vort phasing / tugging and supply the cold air if we’re going to see anything significant here. EU is closest to that happening. Right now elevations (APPs) should see some accumulations

[tron777]

Good morning all! The only thing I have to add to what Bgoney already has posted is that we need the big cutter to pull down the cold air for future systems to work with. The overnight GFS is doing just that. This is the fantasy range obviously, and I should not be posting this, but I have to get some bang for my Accu Wx Buck, right?

Weekend rule?

CVG:

Code: Select all

SAT 12Z 13-JAN  -4.8    -8.0    1015      85      96    0.10     543     531    
SAT 18Z 13-JAN  -2.5    -9.9    1012      89      98    0.18     533     523    
SUN 00Z 14-JAN  -4.8   -11.7    1019      91      97    0.07     533     519  

[tron777]

Looking at the 1/3 - 1/4 system a little more closely, as Bgoney eluded too, from the operational model standpoint, the Euro is the closest one trying to show some partial phasing between the northern and southern jets. The idea has some Ensemble support. Here is the 6Z GEFS showing precip types from the individual members:

GEFS.png

Now let's really start discussing this thing. This is not some fantasy pipe dream as my above post was. This is Days 5 and 6 so worth to invest a little bit of our time in. Do we have enough blocking going on for this thing to come together or is the pattern at that time, still a bit too progressive? To me it's still a bit too progressive. Below, is a hemispheric shot of the 6Z GEFS valid for the same time as the above p-type maps.

gfs-ens_z500a_namer_25.png

As you can see, we don't have a full on -NAO yet. IT is just starting to develop. That does come during Week 2 by the way. EPO is also still positive for this event. This is certainly going to be a thread the needle type of situation for sure. Below will be the EPS valid for the same time. A more suppressed look with the STJ wave and more of a full latitude trough. A colder solution then the GEFS, but less moisture.

eps_z500a_namer_26.png

The rest of the maps will be for the SLP placement from the GEFS and EPS as well as 24 hour QPF from both.

GEFS SLP.png

EPS SLP.png

GEFS Precip.png

EPS Precip.png

So in summation, this is a thread the needle / long shot for wintry weather around Jan 3-4th. But it's really the only thing we've got to keep an eye on other than the fantasy range of course. Let's see what the rest of you think on this one.

[tpweather]

Yes as we head into January already seeing changes as colder air is starting to be on this side of the world. This should at least keep temps near average during the first week of January. Can we get the two jets to play ball and again still believe these will tend to be last minute phasing.

Concerning PV and do we get a split. Finally seeing temps in eastern Siberia heading towards -70 for the first time this season which is no doubt late in the season. The warming if it occurs and it may be doing that already it takes time for the cold to be fully released. Usually it starts out in Siberia where they get really cold for a week or two and if the warming continues then we may see the cold expand to the lower latitudes. I have been worried about the cold in the polar regions because they have been well above normal though we have seen those spokes of cold into the lower latitudes for brief periods.

The southeast ridge and it will one that happens once in awhile but not going to hold up shop because the STJ is very busy and systems will travel across the USA. We do need some ridging and that should mainly be in the Atlantic Ocean.

Okay I mentioned the cold is heading to this side of the world but then you mentioned -70 in eastern Siberia. Key here is eastern Siberia and so close to this side of the planet. If this was in western Siberia and eastern Europe that would not be a good place for us to get colder.

We still have the low southwest of Alaska and part of the puzzle where we need this further south and west to really help funnel the cold to the lower 48.

More later today and then heading back home on Saturday

[tron777]

Yes as we head into January already seeing changes as colder air is starting to be on this side of the world. This should at least keep temps near average during the first week of January. Can we get the two jets to play ball and again still believe these will tend to be last minute phasing.

Concerning PV and do we get a split. Finally seeing temps in eastern Siberia heading towards -70 for the first time this season which is no doubt late in the season. The warming if it occurs and it may be doing that already it takes time for the cold to be fully released. Usually it starts out in Siberia where they get really cold for a week or two and if the warming continues then we may see the cold expand to the lower latitudes. I have been worried about the cold in the polar regions because they have been well above normal though we have seen those spokes of cold into the lower latitudes for brief periods.

The southeast ridge and it will one that happens once in awhile but not going to hold up shop because the STJ is very busy and systems will travel across the USA. We do need some ridging and that should mainly be in the Atlantic Ocean.

Okay I mentioned the cold is heading to this side of the world but then you mentioned -70 in eastern Siberia. Key here is eastern Siberia and so close to this side of the planet. If this was in western Siberia and eastern Europe that would not be a good place for us to get colder.

We still have the low southwest of Alaska and part of the puzzle where we need this further south and west to really help funnel the cold to the lower 48.

More later today and then heading back home on Saturday

Exactly Tim! I mentioned this yesterday. You want the Aleutian Low to be near the tip of the island chain, not near mainland Alaska. As Bgoney also eluded too previously, any attempt at an arctic high trying to drop in from Siberia is negated unless the Aleutian Low is in the correct spot. I am still seeing the Ensemble guidance retrograding it more to the west in time, which is a good thing. We need to see that look hold.

[tpweather]

Yes as we head into January already seeing changes as colder air is starting to be on this side of the world. This should at least keep temps near average during the first week of January. Can we get the two jets to play ball and again still believe these will tend to be last minute phasing.

Concerning PV and do we get a split. Finally seeing temps in eastern Siberia heading towards -70 for the first time this season which is no doubt late in the season. The warming if it occurs and it may be doing that already it takes time for the cold to be fully released. Usually it starts out in Siberia where they get really cold for a week or two and if the warming continues then we may see the cold expand to the lower latitudes. I have been worried about the cold in the polar regions because they have been well above normal though we have seen those spokes of cold into the lower latitudes for brief periods.

The southeast ridge and it will one that happens once in awhile but not going to hold up shop because the STJ is very busy and systems will travel across the USA. We do need some ridging and that should mainly be in the Atlantic Ocean.

Okay I mentioned the cold is heading to this side of the world but then you mentioned -70 in eastern Siberia. Key here is eastern Siberia and so close to this side of the planet. If this was in western Siberia and eastern Europe that would not be a good place for us to get colder.

We still have the low southwest of Alaska and part of the puzzle where we need this further south and west to really help funnel the cold to the lower 48.

More later today and then heading back home on Saturday


Exactly Tim! I mentioned this yesterday. You want the Aleutian Low to be near the tip of the island chain, not near mainland Alaska. As Bgoney also eluded too previously, any attempt at an arctic high trying to drop in from Siberia is negated unless the Aleutian Low is in the correct spot. I am still seeing the Ensemble guidance retrograding it more to the west in time, which is a good thing. We need to see that look hold.

Hey Les, some great info this morning from you. I believe one of the problems is the cold in the polar regions. Sure we have these spokes of cold in Europe and Asia but they are not widespread. The colder air building in Siberia at the moment should help in forming bigger High Pressure systems that will be able to push the Aleutian Low further southwest. That has not happened and a place like Anchorage has got tons of snow this seson.

[tron777]

Thanks Tim! Yeah... Anchorage has been a snow magnet since November really! Check this out from the Anchorage NWS!!! I pulled these stats from their latest climate report.

Seasonal total: 79.5"
Normal to date: 35.3"
Departure: + 44.2"

Current snow depth: 24"

Wow, just wow!

[Trevor]

Look at that high temp ahead of the cold front associated with the bomb!

[tron777]

Look at that high temp ahead of the cold front associated with the bomb!

Could be a squall line of t-storms associated with the cold front should we get that kind of warmth.

[tron777]

Just as a side note while the 12Z OP GFS is running... I still plan on doing individual storm threads like we have done for the past few years. We just have not had anything yet worth creating a thread on both wintry or severe wx wise. It's been tough for the snow and t-storm crowds for quite some time.

[Trevor]

Look at that high temp ahead of the cold front associated with the bomb!

Could be a squall line of t-storms associated with the cold front should we get that kind of warmth.

If we do see a track that far NW, you are correct. In my update on my page today I touched on essentially all precip types possible between 9-12th.

[Bgoney]

GFS closer to what the EU had , higher elevations in the Apps with accumulations. An improvement

[tron777]

GFS closer to what the EU had , higher elevations in the Apps with accumulations. An improvement

You beat me to it! I was going to post the same thing. Definitely a step in the right direction.

[tron777]

Here are the last 4 OP GFS runs. You can see it slowly coming around to the Euro's solution.

GFS Trends.gif

[tpweather]

GFS closer to what the EU had , higher elevations in the Apps with accumulations. An improvement

No doubt and the Apps should do well this season and they have no doubt been in a snow drought for many years. Going to see systems like this over the next few weeks as one run shows no phase at all and then boom a nice phase and then back to no phase. What is up with the nam today showing snow locally

[tron777]

GFS closer to what the EU had , higher elevations in the Apps with accumulations. An improvement

No doubt and the Apps should do well this season and they have no doubt been in a snow drought for many years. Going to see systems like this over the next few weeks as one run shows no phase at all and then boom a nice phase and then back to no phase. What is up with the nam today showing snow locally

To your point Tim, there is another southern slider for the 6th-7th, but that one does not appear to have any cold air to work with unlike the 3rd-4th system.

[Bgoney]

GFS closer to what the EU had , higher elevations in the Apps with accumulations. An improvement

No doubt and the Apps should do well this season and they have no doubt been in a snow drought for many years. Going to see systems like this over the next few weeks as one run shows no phase at all and then boom a nice phase and then back to no phase. What is up with the nam today showing snow locally

To your point Tim, there is another southern slider for the 6th-7th, but that one does not appear to have any cold air to work with unlike the 3rd-4th system.

Yep , pretty excited for Apps to have some good opportunities coming up as you’ve mentioned.


NAM is having a CMC moment

[tron777]

12Z GEFS Precip Type for Jan 3-4th system:

GEFS P Type.png

[winterstormjoe]

12Z GEFS Precip Type for Jan 3-4th system:


GEFS P Type.png

Sign me up for a few of those slides!