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Pattern January 2020 - Operation Thaw Alaska

deltadog03 said:
I agree. I know it’s only 1 run but the euro op really wanted to make this happen. We have all the cold on our side of globe. That’s a good thing to start with.
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Hmmm looks like the Euro ensemble is picking up on this too. A sizable chunk of this Scandinavian high ends up moving over the pole in several days and traps the tropospheric polar vortex over northern Canada & Greenland. Good catch btw

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Jimmy Hypocracy said:
With that EPO doing its thing, If we were able to score a -AO would it only help to strengthen the -PNA or would ridging at the pole begin to drive a new pattern?
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The way we're going to get rid of the -PNA is through a major extension of the North Pacific jet, that requires the MJO to move out into the West-Central Pacific. The AO & NAO usually become negative &/or less positive following a West Pac MJO event, so the -AO >>> +PNA relationship occurs more as a result of happenstance rather than the -AO forcing a +PNA. It's really the change in angular momentum imparted by shifting tropical convection that modifies the Pacific jet stream which directly drives changes in the PNA.
 
Webberweather53 said:
Hmmm looks like the Euro ensemble is picking up on this too. A sizable chunk of this Scandinavian high ends up moving over the pole in several days and traps the tropospheric polar vortex over northern Canada & Greenland. Good catch btw

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Thanks. That in return should force the trod over the Aleutians, sent the ridge poleward to hook up with that ridge moving into Alaska. Then the trof kicks the ridge northwestward to form a -NAO.
 
It seems as if the cold is just waiting for something to kick start it’s way down to where we live... to think we can’t get that kick start through the end of January and into February seems unlikely
 
Nice split on the eps too
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What really sucks is when you look at the pattern evolution over the next 5 days it's raj going as planned ton get a cold January. The okhotsk low forced the Pacific ridge into AK and the cold delivered into the central and eastern us. Problem is tpv lobe rotates around the arctic circle into northern Russia jet accelerates a bit flow in Siberia becomes zonal okhotsk low kicks out Pacific ridge gets cut in half and you end up with an ugly -pna. I say all that to say this, we are likely to repeat a similar process in the d10-20 range. We will probably see some Scandinavian ridging, trough near the urals, Siberian ridge and a low in the okhotsk/aleutians. The question for the Jan 15 onward period are 2 fold: #1 do we actually see some type of -nao/ao construct? #2 do we have enough of a deep okhotsk low that we can force and tilt the Pacific ridge poleward and get a better net result than now? I guess a 3rd question is do we possibly see western us trough actually roll under the Pacific ridge and those anomalies reverse? It's nice to see things looking better in the extended but I have my concerns that we are chasing another transient cold shot.

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The EPS/GEFS project a 2.5/3.0 amp MJO 4/5 late next week. If this one were to peak near 3, would it be a record strong 4/5 for winter? No, because it peaked at 4.1 in Feb of 1985. Also, it peaked at 3.15 in Jan of 1986 and at 3.1 I late Dec of 2018. If it peaks at ~3.0. it would become the 4th strongest on record for winter. THE GEFS does tend to overdo amps although the EPS sometimes is too low. So, I suspect it will peak between them. So, I'm guessing it will peak near 2.75 amplitude in 4/5.

- How many periods on record has there been a ~2.5+ peak of 4/5 in winter? 16
- How many of those 14 had a +NAO? 12 ( 2 were neutral and 2 were -NAO)
- How many of those 14 had a +AO? 8 (5 were neutral and 3 were -AO)
- How many of those 14 had a -PNA? only 4 (3 were neutral and 9 were +PNA)
- How many of those 14 had a +EPO? 10 (2 were neutral and 4 were -EPO)

- How many of these 16 periods were AN at KATL? Only 10 with 5 BN; The 16 periods averaged +2
- Average length of strong 4/5 in winter? 6 days or about how long the upcoming one is projected to be
- The warmest anomalies were these: +12, +10, +9, +9, +8, +7, +7, +4, +3, +3, +1
- The coldest anomalies were these: -10, -8, -5, -5, -4
- The coldest anom of -10 was for 1/20-31/1978, when there was -AO, +PNA, and -EPO to go along with +NAO. Also, that was a wk Nino.
- The 2nd coldest anom of -8 was for 1/6-7/2015, when there was a +PNA/-EPO to go along with +NAO/+AO. Also, that was a wk Nino.
- The 3rd coldest anom of -5 was for 2/12-22/1985, when there was a -AO/+PNA to go along with neutral NAO/+EPO.
- The 4th coldest anom of -5 was for 2/1-8/2004, when there was - -NAO/+PNA to go along with a neural AO/+EPO.

For the upcoming one, the GEFS forecast is for a +NAO/+AO/-PNA and I think a +EPO is being forecasted, also. So, that is like all 7s for warmth on the "indices slot machine.". So, a very warm period close to the warmest of the ones I listed, +7 to +12, wouldn't surprise me.

****EDIT: I just incorporated 2 additional periods (both from Dec of 2018) that I had accidentally left off.
 
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GaWx said:
The GEFS/EPS project a 2.5-3.0 amp MJO 4/5 late next week. If this one were to peak near 3, would it be a record strong 4/5 for winter? No, because it peaked at 4.1 in Feb of 1985. Also, it peaked at 3.15 in Jan of 1986. If it peaks at ~3.0. it would become the 3rd strongest on record for winter. THE GEFS does tend to overdo amps although the EPS sometimes is too low. So, I suspect it will peak between them. So, I'm guessing it will peak near 2.75 amplitude in 4/5.

- How many periods on record has there been a ~2.5+ peak of 4/5 in winter? 14
- How many of those 14 had a +NAO? 12 ( 1 was neutral and 1 was -NAO)
- How many of those 14 had a +AO? 7 (4 were neutral and 3 were -AO)
- How many of those 14 had a -PNA? only 4 (3 were neutral and 7 were +PNA)
- How many of those 14 had a +EPO? 8 (2 were neutral and 4 were -EPO)

- How many of these 14 periods were AN at KATL? only 9 with 5 BN; The 14 periods averaged only +1
- Average length of strong 4/5 in winter? 6 days or about how long the upcoming one is projected to be
- The warmest anomalies were these: +12, +10, +9, +9, +8, +7, +4, +3, +3
- The coldest anomalies were these: -10, -8, -5, -5, -4
- The coldest anom of -10 was for 1/20-31/1978, when there was -AO, +PNA, and -EPO to go along with +NAO. Also, that was a wk Nino.
- The 2nd coldest anom of -8 was for 1/6-7/2015, when there was a +PNA/-EPO to go along with +NAO/+AO. Also, that was a wk Nino.
- The 3rd coldest anom of -5 was for 2/12-22/1985, when there was a -AO/+PNA to go along with neutral NAO/+EPO.
- The 4th coldest anom of -5 was for 2/1-8/2004, when there was - -NAO/+PNA to go along with a neural AO/+EPO.

For the upcoming one, the GEFS forecast is for a +NAO/+AO/-PNA and I think a +EPO is being forecasted, also. So, that is like all 7s for warmth on the "indices slot machine.". So, a very warm period close to the warmest of the ones I listed, +7 to +12, wouldn't surprise me.
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