GaWx

5 hours ago, mitchnick said:

September Jamstec. It may not get the forecast right, but it'll at least get you to make an optometrist appointment. 

 

-Sep Jamstec winter forecasts going back to 2017-8 are available at the site to compare to

-Sep ‘26 is vs all Sep forecasts back to ‘17 by a good margin the coldest DJF in the CONUS overall, by a very wide margin the coldest DJF in the E 1/2 overall, and is easily the coldest for the SE, midsouth, S Plains, Ohio Valley, and Mid-Atlantic. I couldn’t even find a colder one than this for the corridor from Chic to NYC.

-Sep ‘26 is the wettest overall for the E US vs the other Sep DJF forecasts

-June-Sep ‘26 are all very similar in the CONUS for DJF ‘26-7 and are the most consistent of any DJF forecasts back to 2017-8!

 Here’s the ‘23 Sep forecast for DJF for comparison (the 2nd coldest since ‘17): coldest is -0.5 to -1C:

Compare that to ‘26: like night and day with coldest -2 to -3C! This would easily be the coldest winter for the SE, Mid-South, and S Plains since 2014-5. Also, note how much colder is the Arctic vs ‘23-4. Keep in mind that the Arctic N of 80N from late May through summer was easily the coldest since 1958 for unknown reasons:

How did Sep JAMSTEC verify in the E US overall?

’17: too warm NE/close SE

’18: close NE/too cold SE

’19: too cold

’20: close NE/too warm SE

’21: N/A

’22: too cold

’23: too cold

’24: too warm

’25: too warm

So, for these 8 winters, Jamstec:

-in NE was too warm 3 times, too cold 3 times, and close twice…so neutral bias averaged out

-in SE was too warm 3 times, too cold 4 times, and close once…so, very slight cold bias but pretty neutral overall averaged out 

-Keep in mind that this cold E US forecast is with Jamstec progging an E based super Nino.

1 hour ago, LakePaste25 said:

To verify sure, there’s no requirement in how one gets there. It’s more about trusting the prognosis to begin with. 

Say it’s 100 in Atlanta. A model says starting tomorrow, we will see the forecast high drop 5 degrees every day for the next 6 days. So in a few days it’ll only get to 80 in Atlanta. 

It’s now tomorrow, and the high didn’t drop 4 degrees. It’s 99. Continue on to the next day, it’s 100 again. Why should I trust what the model is saying 3 weeks out when it’s making such a massive forecast error 2-5 days out? 

 I and others have been posting what the model trend has been for later this autumn for the various Nino regions (clearly downward), but am not suggesting anyone “trust” what the CFSv2 (or any model for that matter) shows since model progs sometimes verify poorly. Regardless of model imperfections though, a good portion of this and other forecasting discussion threads typically centers around the trends of model output even though the output isn’t typically “trusted”. Models are very useful tools even though they’re not at all crystal balls and thus can bust badly.
 

 I’ve found over the many years that I’ve been following them that model prog trends are quite worthy of discussion since they often give good hints on what’s actually liable to occur down the road regardless of their imperfections.
 

 A good example of another current forecasting discussion thread that follows model trends is this one in the Mid-Atlantic forum that I and some others here also post in and which I recommend others check out:

 Today’s weekly relative update (which has been NOAA’s official way of measuring these for quite awhile now) for last week cooled in Nino 1+2 from +3.9 to +3.7 and in Nino 4 from +0.1 to -0.1. Meanwhile, Nino 3 warmed from +2.7 to +2.8 while Nino 3.4 warmed from +1.8 to +2.0:

02SEP2026         3.9        2.7        1.8        0.1
 09SEP2026         3.7        2.8        2.0       -0.1

 This is the comparable week in 1997:

10SEP1997         3.8        2.6        1.8        0.5

 This tells me that 2026 remains more E based than 1997 and was thus for another week the most E based on record for this time of year.

 Today’s SOI is at ~-26. That’s the 33rd straight -SOI. The 30/90 day averages are at -17.5/-20.3:

https://www.longpaddock.qld.gov.au/soi/

 The AAM yesterday finally for the first time this month exceeded an impressive +3 per the following image after several early Sep runs had had that occurring by Sep 7-8th. The delay is typical due to a + bias of the CFSv2.

 This is saying it will hit an extreme level of +4+ in only ~5 days (~Sep 19th), which is the earliest in its forecast that I’ve ever seen it reach it, and that it will stay +4+ at least through Sep 24th. I’ll keep following these graphs to see if that actually occurs:

10 minutes ago, forkyfork said:

do you really think it's going to immediately start falling

It was initialized at +4.6 for the full Sept averaged out. The mean then has +3.9 for Oct averaged out. There’s no requirement that the highly volatile 1+2 fall immediately for both of these to verify well.

17 minutes ago, LakePaste25 said:

So it’s already initialized too low? Toss IMO. 

Why do you say it’s initialized too low?

6 minutes ago, mitchnick said:

Enso 3.0 down too.

1+2 also dropping:

8 hours ago, GaWx said:

3.4 peak still cooling!

That was an earlier update. Check out the latest: down to +2.9 peak/blues still lower than reds thru NDJ:

5 minutes ago, LakePaste25 said:

The MJO isn’t “avoiding” the IO/MC, it’s being suppressed by the descending branch of the hadley cell triggered by the Nino standing wave whenever it enters that region. If you use VP and OLR plots you can still see the MJO pass thru those regions in a very suppressed state. On the RMM plot, El Niño is overwhelming the signal. 

Why is it overwhelming the signal on RMM now but in 97-8 it was nearly opposite (majority in MC/IO)?

42 minutes ago, GaWx said:

 The MJO continues to avoid the Maritime C and IO like no other time on record:

And here’s the 2 week fcast below. Does anyone know why the MJO is avoiding the IO & MC?

I looked at the other 16 Ninos since 76/7 and found only two others only somewhat similar in JAS:

2015: still had good # in IO

1994: still had large # in MC

 The MJO continues to avoid the Maritime C and IO like no other time on record:

Per this the min of 3.6 may have already been hit. If so, that’s well above the worst:

I think this is the 5th run in a row and 7th overall with a Medi-TC!
 

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER  36 HOURS
              FORECAST POSITION AT T+ 36 : 34.1N  18.4E

                        LEAD                 CENTRAL     MAXIMUM WIND
      VERIFYING TIME    TIME   POSITION   PRESSURE (MB)  SPEED (KNOTS)
      --------------    ----   --------   -------------  -------------
    0000UTC 15.09.2026   36  34.1N  18.4E     1010            32
    1200UTC 15.09.2026   48  34.5N  20.8E     1004            41
    0000UTC 16.09.2026   60  34.3N  22.6E     1006            39
    1200UTC 16.09.2026   72  34.5N  24.9E     1006            30
    0000UTC 17.09.2026   84  36.3N  27.9E     1007            29
    1200UTC 17.09.2026   96              CEASED TRACKING

35 minutes ago, SnoSki14 said:

This is moronic on both levels. Thanking Trump for no hurricanes and saying it's due to anti-climate policies. 

Indeed. But Parnas is smart enough to know better. That’s a huge blunder for him. Typical DT supporters OTOH….though I’m suspecting trolling .

23 minutes ago, LongBeachSurfFreak said:

Allot goes into OHC. But the main function of hurricanes is to redistribute heat from the tropics to the poles. OHC can absolutely build year over year. Deep OHC in the 100-300m zone is not impacted by local winds. It takes the upwelling caused by major hurricane winds to cause the water column that deep to overturn.


.

 CC has caused the poles to warm much more rapidly than the tropics. Thus, there’s less of need to move heat from tropics to poles. In theory that should mean a net drop in TCs. Although the ATL basin has yet to exhibit this (ignoring 2026, which is super Nino related), the W PAC sure has overall (esp when ignoring Nino related ‘26). Maybe the ATL will eventually have a CC related reduction, especially when -AMO returns.

No, A. Parnas, the super Nino is not caused in part due to DT anti-climate policies!

Remember this 9/5 CFSv2 AAM run progging 3+ starting Sep 8th and 4+ starting Sep 15?

Compare that to the latest released (9/12) showing 3+ not til Sep 15th and 4+ not til Sep 19th!

3.4 peak still cooling!

We’re getting hit hard with what looks like a severe thunderstorm even though it’s not warned yet! It started at 7:15PM.

Edit: total for 9/11/26 was ~0.6”, which brought my MTD up to ~2.0”.

On 9/8/2026 at 12:48 PM, GaWx said:

Not Atlantic basin per se but this is interesting:

The UKMET has for the 2nd run in a row a TC in the Mediterranean Sea:

12Z UKMET:

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 132 HOURS
FORECAST POSITION AT T+132 : 35.8N 21.0E

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
0000UTC 14.09.2026 132 35.8N 21.0E 1008 31
1200UTC 14.09.2026 144 38.7N 24.0E 1007 27
0000UTC 15.09.2026 156 40.5N 24.6E 1007 27
1200UTC 15.09.2026 168 39.6N 22.6E 1008 25

 After having a Medi-TC on both Sep 8th UKMET runs (TCG late 9/13 to early 9/14), the subsequent 5 runs’ textual output showed nothing. But the newest UKMET (12Z 9/11 run) brought it back albeit slightly delayed vs the two 9/8 runs with TCG ~18 hours later. This run gets it all of the way down to 986 mb. Wouldn’t it be amazing for the Mediterranean to have a TC stronger than the strongest so far in the Atlantic?

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 78 HOURS
FORECAST POSITION AT T+ 78 : 34.5N 13.5E

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
0000UTC 15.09.2026 84 34.1N 14.1E 1010 30
1200UTC 15.09.2026 96 35.3N 16.5E 1003 43
0000UTC 16.09.2026 108 35.8N 16.7E 998 51
1200UTC 16.09.2026 120 35.4N 15.6E 993 46
0000UTC 17.09.2026 132 35.0N 17.3E 992 41
1200UTC 17.09.2026 144 35.1N 19.7E 989 51
0000UTC 18.09.2026 156 35.0N 22.5E 986 60
1200UTC 18.09.2026 168 35.2N 26.1E 991 48

@LongBeachSurfFreak

7 minutes ago, 40/70 Benchmark said:

How about region 4?

Nino 4 on latest UKMET strengthened slightly from a peak of ~+1.3 in Sep on the Aug run to a peak of ~+1.4 in Nov on the new run:

Aug run: peak of ~+1.3 in Sep (non-relative)

Sep run: peak of ~+1.4 in Nov (non-relative)

The UKMET, which pretty much nailed the 2023 ONI peak of ~+2.0, just updated for Sept: it peaks at ~+3.3 in Nov:

 The prior run (Aug) had peaked at only +3.1:

Regarding Nino 1+2, it also strengthened:

New run: a little >+4 (this like for 3.4 above is not relative and thus doesn’t taken into account GW well):

Prior run (Aug): ~+3.8

Mean of last 3 days worth of CFSv2 runs has this for Sep 25-Oct 1st: