GaWx

 Today’s GEFS and EPS MJO forecasts both have a 2+ amplitude (strong) phase 6/7 starting in week 2:

-GEFS has 2+ amp phase 6 for Jan 17-21 with a peak at ~2.6 on 1/21 (often strong GEFS forecasted MJOs verify a bit weaker in this region fwiw)

-EPS has ~2+ amp phase 6-7 (mainly 7) for Jan 16-21 with a peak at ~2.2 in phase 7 on 1/19 (sometimes EPS forecasted MJOs verify a bit stronger in this region fwiw)

- These tell me that the chance for Jan to end up with 20+ days on or inside circle is decreasing.

- The frequency of MJO amps of 2+ in DJF has increased substantially on a multi-decadal basis (climate change suspected):

# of days MJO 2+ amplitude per DJF

70s-80s: 11

90s-00s: 17.5

10s-20s: 23

 So far, 2025-6 has had 4 days of 2+ amp (Dec 1-4)

 These Jans had a 2+ amp phase 6 or 7:

-2024

-2021-18

-2016-3

-2011-8

-2006

-2004

-2002

-1997

-1993-2

-1990-89

-1986

-1979

-1976

 Note how much less common phase 6-7 periods with 2+ amp were in Jan during 1975-2001 (only 30% of the Jans) vs 2002-2025 (67%)!

——————
 Here’s another MJO stat. tidbit:

# of days per phase Jans 2011-25 (465 total days)/% of Jan days per phase

1: 17 (only 4%)

2: 26 (only 6%)

3:   67 (14%)

4:  51 (11%)

5:  57 (12%)

6:  101 (a whopping 22%)

7:  104 (a whopping 22%)

8:  42 (9%)

So, since 2011, each of Jan phase 6 and 7 days has been more than twice as common as phase 8 days and a whopping FOUR TO FIVE times as frequent as each of Jan phase 1-2 days!

@bluewave

 These CFS ens AAM forecasts are volatile especially for later in the forecast period. So fwiw, the latest forecast mean is the most bullish yet for a rising AAM starting in ~2 weeks and actually going modestly positive (El Nino-like) in ~3 weeks:

 With El Niño favored for next fall/winter, I looked at E US temps during multiyear La Niña Febs that immediately precede El Niño:

1911: cool NE/mild elsewhere

1918: cool NE/mild SE

1972: cool

1976: warm

2009: mild NE/NN SE

2018: warm

2023: warm

Feb: SE temps/RDU snow

1911: 1 AN/0”
1918: 3 AN/T and some ZR
1972: 5 BN/1.4” SN/IP
1976: 5 AN/T
2009: 1 AN/T
2018: 7 AN/0”
2023: 9 AN/0”

Average of these 7 Febs at RDU: 3 AN, 0.2” SN/IP

Of the 7:
-one was cold
-two were NN
-four were mild to warm

 So, these analogs favor the @snowman19mild Feb thinking in the SE. So, if we get another 2/2014 like I think both@40/70 Benchmarkand Eric Webb are more or less favoring (correct me if I’m wrong), I’d be thrilled since these analogs don’t favor it. 
 
 In the NE, these analogs are mixed with 3 BN and 4 AN.

Here’s the avg of the 7 Febs: check out how warm the SE, Midsouth, lower MidAtlantic, and OH valley are:

23 minutes ago, Stormchaserchuck1 said:

We're not going to hit La Nina on the ONI. It's going to officially be "ENSO Neutral" for the 2nd straight year. 

Chuck,

 But for the second straight year it will be a borderline weak/moderate Niña based on RONI:

https://www.cpc.ncep.noaa.gov/data/indices/RONI.ascii.txt

From Eric Webb, he’s clearly on the 2013-4 and seems excited:

On 1/5/2026 at 10:35 AM, snowman19 said:

I’m not sure how much we can trust the MJO progs all the way into the start of February based on how utterly awful they were for December. But that aside, the thing I definitely doubt is 5 months of below normal cold in this new CC regime, which is most pronounced in winter. We have been lucky thus far to have seen November, December and the start of January see below normal cold. I just cannot see all 5 months in a row (Nov, Dec, Jan, Feb, Mar) averaging below normal cold. We haven’t seen a La Niña that averaged all 5 months in a row below normal in over 30 years (95-96) and that was well before CC really started

Today I estimated that a significant portion of the E US (at least the area from Chicago to much of the SE) will end up ~5-6 warmer than normal for the first half of Jan. With that, the chance of Jan overall coming in cold is low and warmer than normal overall has a better chance. So, the cold month string will be broken most likely. Plus Dec was mainly NN from the SE to the SL area meaning Dec’s cold didn’t even come close to covering the entire E US.

Here’s a link to the last video from Michael Clark, done on 12/30 in which he was highly confident and even smug:
 

 From this 12/30 video, he posted a forecast map for 12/31-1/15 showing most of the E US (Minneapolis to SL to ATL eastward) BN. Instead it is headed toward solidly AN. I project Chicago, ATL, and RDU will end up ~+5 to +6 for 12/31-1/15. He forecasted Chic at -3 to -4 and ATL/RDU at -1 to -2. BAM is headed toward a miss of -6 to -9 for 12/31-1/15 in a good portion of the E US!

@donsutherland1

2 minutes ago, MJO812 said:

I dont see the models backtracking with the cold. 

I think it’s BAMwx having been colder than the models and now being forced to backtrack.

Bamwx backtracking today for the medium range:

2 hours ago, snowman19 said:

No one in their right mind is going to argue that this Niña isn’t collapsing or that we aren’t going to see a substantial El Niño develop this spring, granted. My issue is this fantasy going around twitter (NOT saying Webb is saying this) that a full blown El Niño pattern is going to take over by February. That wishcast is going to go down in flames and it’s completely preposterous. It takes months for the atmosphere to flip from one completely different ENSO state to another. There is always a lag, no matter what

Thanks, snowman.
 Yeah, Eric Webb of course knows this and thus isn’t at all saying that a full blown Nino pattern will set in by Feb. But he is as I already posted excited about E US potential in Feb as he’s been saying in recent days that a 2014 type of Feb is becoming increasingly possible. We’ll see but at least he’s laying this out and not being shy.

 Any guess yet as to the strength of the upcoming El Niño assuming it actually does occur?

12 minutes ago, WinstonSalemArlington said:

Juneuary

1. The good news is that this is very old news as regards the models.

2. In addition, for the SE this for the most part will likely not be nearly as warm as the late Dec torch nor as long.

3. This refers to today through Monday. But in reality the warmth ends with a transition by Sat night.

From Eric Webb this morning:

The is one of the most impressive mid-winter collapses of La Nina I’ve ever seen. 

If you’re still in a Nina, you are definitely not supposed to see westerly wind bursts drive this deep into the Pacific, with or without an MJO event

3 hours ago, MJO812 said:

We just need the PNA to be in our favor which it looks like it might . 

 Per WxBell’s version of the GEFS’ mean PNA, the trend of the last few days for both the length and strength of the midmonth +PNA has been a sharp increase: watch as the midmonth green line above 0 on each of these images gets longer and peaks higher:

- 0Z 1/2 run: <1 day >0 (Jan 12th); max amp +0.1 (Jan 12th)

- 0Z 1/3 run: 3 days>0 (Jan 11th-13th); max amp +0.5 (Jan 12th)

- 0Z 1/4 run: 4.5 days>0 (Jan 10th-14th); max amp +0.7 (Jan 11th)

-0Z 1/5 run: 6 days>0 (Jan 9th-15th); max amp +1.2 (Jan 13th)

-18Z 1/5 run: 8 days>0 (Jan 9th-17th); max amp +1.7 (Jan 14th)

Here are those 5 images in a GIF:

1 hour ago, MJO812 said:

You love the weeklies.  It hasn't been accurate at all .

1. I just present what I see, whether something I want or not on whatever I’m presenting.

2. It’s the best we have for long range guidance. Nothing in the long range does great because that’s beyond the models’ abilities.

3. EW is a tool and nothing near a crystal ball. But it often gives a halfway decent idea of what’s to come. Look at what it showed last year on this day, which all verified pretty well:

 After the +PNA leaning week of 1/12-18, which gives the SE NN/coldest anomalies of E US, today’s Euro Weeklies continue with the idea of a stronger than avg gradient N to S. The -PNA returns ~1/17 and the week of 1/19-25 has the SE with NN in NC to slightly AN GA and it has moderately BN in New England. The subsequent 3 weeks all warm due to a continued -PNA and warm to NN NE and modestly AN SE though one can see the CADdies in the SE are helped on certain days thus keeping them only barely AN in the means.

 The Weeklies now go through Feb 15th. So far, they’re showing no sign of a cold Feb anywhere. But hopefully that will drastically change!

 I sure hope it’s prog of a -PNA 1/17-2/15 is going to be dead wrong!

 The 12Z GEFS and EPS did go colder than 0Z/6Z late in the runs. However, it and 12Z EPS still go to a -PNA late. Hopefully those will change within the next few days. Otherwise, the best the SE can reasonably hope for imho are just short cold periods/ups and downs as any sustained cold stays to the north (strong gradient pattern N to S).

18 minutes ago, snowman19 said:

I’m not sure how much we can trust the MJO progs all the way into the start of February based on how utterly awful they were for December. But that aside, the thing I definitely doubt is 5 months of below normal cold in this new CC regime, which is most pronounced in winter. We have been lucky thus far to have seen November, December and the start of January see below normal cold. I just cannot see all 5 months in a row (Nov, Dec, Jan, Feb, Mar) averaging below normal cold. We haven’t seen a La Niña that averaged all 5 months in a row below normal in over 30 years (95-96) and that was well before CC really started

1. But Jan as a whole may not end up cold if the -PNA returns midmonth. If not, that breaks the cold streak.

2. My Feb post didn’t say anything about March.

 Back to the Jan PNA, this 24 hour change of the GEFS mean does show how quickly forecasts can change:

 24 hours ago (1/4 forecast): rose to neutral Jan 10th but that was it as it then aimed slowly downward afterward with only 4 members staying +PNA to the end:

Today (1/5 forecast): rises to neutral Jan 9th and quickly goes to a +PNA for a week, a significant + change. However, the mean then heads back down to neutral. That being said, note that there are more members (~10/33%) that stay + to the end (1/19) vs only 4 yesterday. What that 1/3 of members is doing is the kind of thing we need going past midmonth to have a good shot at a +PNA Jan like numerous analogs had been suggesting has a high chance:

 So, unless the +PNA hangs on instead of switching back within a week like the ensembles show, we’d likely not end up with a BN Jan. 

 But we can still look ahead to Feb., which has some encouraging signs:

1. There are long range model progs that the MJO will be headed into 8 near the start of Feb:

2. Though the CFS AAM outlook often jumps around and thus can’t be trusted, the latest does have a reversal to an El-Ninoish +AAM very late in Jan.

3. Webb is now optimistic about Feb. And @40/70 Benchmarkremains optimistic about a cold Feb.

 Looking at the bigger picture of the 100% of -ENSO -PNA Decs since 1983-4 that switched to a +PNA for Jan: none of them did what the ensemble means are showing, which is a 6-7 day long +PNA that starts Jan 9-10 but unfortunately then turns back to a -PNA for the rest of the runs. That would seal the deal for no +PNA for Jan as a whole, which obviously is not at all what I would want to see and would be a first for -ENSO since 1983-4.

 So, either the ensemble means very soon change their tune for 1/16+ to not go back toward a -PNA or the chance of getting a +PNA Jan is “cooked” using the term some of you guys like to use. Being that 1/16 is still 11 days out and considering the -PNA model bias, there’s still time for that to change. But if we don’t see this start to change within the next few days, the chance of getting a +PNA Jan will drop dramatically.

Reflecting on milder E US forecasts, NG is way down this morning (-6%).

I just got an enjoyable walk in this evening with mid 40s, calm winds, and some cool looking fog that had formed especially over the warmer water with RH.% in the 90s.

Jan update of MJO through Jan 2nd: finally heading back the other way inside the circle. So the first two days of Jan are on or inside circle. 12/29-1/2 were in phase 5:

1 hour ago, wncsnow said:

It looks to get to near normal at least next week

I’m looking forward to a NN averaged week next week which should include some BN (assuming it verifies), with its largely Canadian airmass influenced chilliness…great for walking…always welcomed! The upcoming mid-week to weekend of semi-torching to torching won’t be too fun for that .

OND RONI -0.92

OND ONI -0.55

So, OND RONI was 0.37 lower than OND ONI. That difference was a similar 0.35 for SON meaning the difference has been pretty steady for awhile.

22 minutes ago, Ji said:

people are making too big of a deal of MJO phase 6. If this is correct...its a 2-4 day thing where irs out of the neutral circle

Ji/Mitch

 I agree that folks are making too big of a deal about phase 6 and BAMwx’s map is much too cold as I said. My own research looked at phase 6 including phase 6 inside the circle and it was as I said not nearly as cold as that BAMwx’s map for all cases averaged out (-2 at GSP vs BAM’s -6 to -7). Based on the latest ext GEFS, phase 6 is currently forecasted to last 9 days (14th-22nd) while it lasts 7 days on the ext EPS (14th-20th). So, both have 7 days (14th-20th) in phase 6. But of course they’ll likely not verify exactly and may end up not close. And even if close, the variance of temperatures for Jan La Niña phase 6 is large.

@mitchnick