Severe Weather 2021

[andyhb]

Don't think we're going to get sufficient moisture return for the Feb 3-6 system if that nor'easter around the turn of the month just sits there for days. Too much ridging downstream/to the north.

 

[rolltide_130]

Last night's GFS is hinting at another system to start cranking around mid-February. This is looking a bit more low-amplitude with a more favorable downstream ridge positioning than what we had previously.

Obviously I'm not trying to highlight the individual system this far out, but the overall lower-amplitude pattern evolution being depicted is the next step towards a major event at some point during the spring this year.

 

[andyhb]

Strengthening of both the -PDO (cooling over the NE Pacific and warming west) and +TNI signatures (Nino 1.2 warming faster than Nino 4) over the past week via CDAS. We’re now comfortably in a “Modoki” La Niña configuration.

 

[KevinH]

View attachment 5801

Strengthening of both the -PDO (cooling over the NE Pacific and warming west) and +TNI signatures (Nino 1.2 warming faster than Nino 4) over the past week via CDAS. We’re now comfortably in a “Modoki” La Niña configuration.

Pardon my ignorance (I am new), but what does Modoki mean and what could that mean for Spring? I am guessing nothing good??

 

[andyhb]

Pardon my ignorance (I am new), but what does Modoki mean and what could that mean for Spring? I am guessing nothing good??

Modoki means the cold sea surface temperature anomalies in the equatorial Pacific associated with La Nina are further west than usual in a typical La Nina. It sets up a configuration in the SSTA patterns that has been present for a number of active severe weather seasons in Dixie.

 

[KevinH]

Modoki means the cold sea surface temperature anomalies in the equatorial Pacific associated with La Nina are further west than usual in a typical La Nina. It sets up a configuration in the SSTA patterns that has been present for a number of active severe weather seasons in Dixie.

OK, so just more talk of what everyone has been saying lately: This year Dixie Alley MAY get its donkey whooped in a way it has not seen since 2011 because of how things have been lining up in recent weather patterns.

Great.

I live in Dixie and it will be very interesting to see how things are looking in mid to late February.

 

[Fred Gossage]

OK, so just more talk of what everyone has been saying lately: This year Dixie Alley MAY get its donkey whooped in a way it has not seen since 2011 because of how things have been lining up in recent weather patterns.

Great.

I live in Dixie and it will be very interesting to see how things are looking in mid to late February.

That's a bit early. The MJO has gone back into the Pacific, and that helps drive the pattern suppression we have seen so far this winter. It doesn't mean we won't have any threats, but the main action likely isn't going to start that soon. The MJO will head back toward phases supportive of traditional La Nina forcing deeper into February. I think the main action starts to pick up with time in March, and especially in April.

 

[Fred Gossage]

View attachment 5801

Strengthening of both the -PDO (cooling over the NE Pacific and warming west) and +TNI signatures (Nino 1.2 warming faster than Nino 4) over the past week via CDAS. We’re now comfortably in a “Modoki” La Niña configuration.

Here's a look at the SSTAs as of a couple days ago from an alternate source. We've seen a few times this year that the daily CDAS numbers from Tidbits has been off a few 0.XC. Regardless of what those numbers have, this shows that we have a screaming +TNI in place now, further backing up your thoughts about it intensifying, and we're already seeing the classic, textbook -PDO horseshoe configuration developing, which continues to intensify, as you have mentioned.

 

[Fred Gossage]

Here is the Euro projection of the MJO through the end of February. We see it in a low to mid amplification through the western Pacific now. That continues through at least the first half of February before it deamplifies and heads toward the "circle of death". Once it is there, the La Nina background state will have nothing holding it back from being the pattern driver for the pattern as we head into March and April. This is a classic configuration for holding the pattern suppressed until the start of spring severe season so that the polar jet does not shift north of Dixie Alley until it does what it wants to in March and April, and we have seen this in several of the high profile analog years previously mentioned in this thread.

 

[KevinH]

That's a bit early. The MJO has gone back into the Pacific, and that helps drive the pattern suppression we have seen so far this winter. It doesn't mean we won't have any threats, but the main action likely isn't going to start that soon. The MJO will head back toward phases supportive of traditional La Nina forcing deeper into February. I think the main action starts to pick up with time in March, and especially in April.

Oops.. I should have clarified something. LOL! I was not saying that our severe events would start in February LOL. I read somewhere (probably on this thread I think) that there is going to be some change in mid to late February that will further "set the stage" for what we are thinking is going to happen in March and April. I cannot remember exactly what it was, but I believe the change I am thinking of is the MJO heading back.

I hope things do not pan out the way they have been trending, but time will tell, and I will keep watching (and asking questions lol).

 

[Fred Gossage]

Overnight CDAS derived ENSO data on Tidbits has Region 1+2 now positive (+0.003), and Region 4 is still below -1 and dropping again (-1.058). That gives a TNI of +1.061, but we also know when comparing Tidbits numbers to CPC released weekly data that Tidbits has been 0.2-0.3 too warm with its Region 4 numbers, and it has varied in magnitude but has been a little too cold with warmer areas. Because of that, the TNI may actually be as high as +1.2 or higher and steadily climbing. This look below would certainly support that idea...

 

[KevinH]

Overnight CDAS derived ENSO data on Tidbits has Region 1+2 now positive (+0.003), and Region 4 is still below -1 and dropping again (-1.058). That gives a TNI of +1.061, but we also know when comparing Tidbits numbers to CPC released weekly data that Tidbits has been 0.2-0.3 too warm with its Region 4 numbers, and it has varied in magnitude but has been a little too cold with warmer areas. Because of that, the TNI may actually be as high as +1.2 or higher and steadily climbing. This look below would certainly support that idea...

View attachment 5806

So in other words....? lol

 

[Fred Gossage]

So in other words....? lol

It's everything we've already been talking about for a while in this thread...

 

[KevinH]

It's everything we've already been talking about for a while in this thread...

OK, more of the same thing, got it!

I just came across these articles that were a little helpful:
https://climatedataguide.ucar.edu/climate-data/nino-sst-indices-nino-12-3-34-4-oni-and-tni &

Is There an Optimal ENSO Pattern That Enhances Large-Scale Atmospheric Processes Conducive to Tornado Outbreaks in the United States?

Abstract The record-breaking U.S. tornado outbreaks in the spring of 2011 prompt the need to identify long-term climate signals that could potentially provide seasonal predictability for U.S. tornado outbreaks. This study uses both observations and model experiments to show that a positive phase...

journals.ametsoc.org

 

[warneagle]

We've got a little mini event going on in northeast Oklahoma and northwest Arkansas.

 

[rolltide_130]

January's SOI came in at the 5th highest value ever since recording began, behind 1939, 1962, 1974, and 2011

 

[tennessee storm chaser]

January's SOI came in at the 5th highest value ever since recording began, behind 1939, 1962, 1974, and 2011

1974 seems to be a big analog used for this upcoming spring season

 

[KevinH]

View attachment 5803
Here is the Euro projection of the MJO through the end of February. We see it in a low to mid amplification through the western Pacific now. That continues through at least the first half of February before it deamplifies and heads toward the "circle of death". Once it is there, the La Nina background state will have nothing holding it back from being the pattern driver for the pattern as we head into March and April. This is a classic configuration for holding the pattern suppressed until the start of spring severe season so that the polar jet does not shift north of Dixie Alley until it does what it wants to in March and April, and we have seen this in several of the high profile analog years previously mentioned in this thread.

Is the pattern flip of the MJO related (at all) to the bouts of cold weather we are expecting in February?

 

[KevinH]

1974 seems to be a big analog used for this upcoming spring season

Where do you see these analogs that show 2011, 1974, etc?

 

[tennessee storm chaser]

Where do you see these analogs that show 2011, 1974, etc?

Cips using it... one of the years .