GaWx

1 hour ago, so_whats_happening said:

It does start to become noticeable when you take a look at things in this perspective. Southern hemisphere and tropics still humming along as they have been.

The mean global AAM based on this is not much above 0…+0.5 at most, not at all jibing with the Sep 17th +3.3. I don’t get it.

6 hours ago, Winter Wizard said:

An interesting thing about the GLAAM is that when it's plotted on a latitudinal basis, it's actually shown to be strongly in the negative direction around the mid-latitudes. It almost looks like a glitch but it has been moderately to strongly negative at various other points since July. Perhaps some interference somewhere?

Indeed, the weighted avg of your graph, which looks like it is only ~+1.25 to 1.5, doesn’t at all jibe with the image below, which shows it ~+3.3:

12Z UKMET: again says no Gulf TC

5 minutes ago, Windspeed said:

1 hour ago, GaWx said:

 Despite the Euro having something in the Gulf late, ironically the crazy GFS has no Gulf TC on its 6Z for the 1st run since way back at 18Z of 9/14! It just has one moving just N of Cuba (not in Gulf) at 384.

It still does have a system / vorticity breaking off of the CAG 130'ish hours into the 6Z run, it just fails to develop a fully fledged TC and bring that into the GOM. That could just as easily come back on the 12z today. Again, chaotic. Though, yes, it also breaks off vorticity and develops a hurricane late in the run. Meh, these simulations will remain complete choas until something actually resolves. If anything can be taken from these runs at this point, it's to say we should have a warbling surface trough gyre establish itself by this weekend over central America and we just need to watch for any pieces of energy and vorticity that may break off on either side of the landmass (EPAC or WCARIB) for potential development over the next few weeks.

The MJO is heading toward favorable phases for TCG at this time of year, which Joe Bastardi has been appropriately emphasizing in his call for activity:

6 hours ago, Windspeed said:

Lol at tonight's GFS 00z operational. I made a post during the previous week that modeling of any potential CAG system was going to be rather chaotic until something actually resolved. That has definitely been the case. Still, if something develops and gets in the right position at the right time, potential exists for a powerful system given the potential favorable upper environment that should evolve over the GOM next week. If nothing else, it's something to watch. Mind you, though the UKMet and GFS suites continue flirting with a system, the Euro suites haven't been bothered yet. I should add it's not that Euro doesn't have the CAG there, it just transfers that energy or resulting vorticity into the EPAC instead of trying to resolve something in the WCARIB or GOM.

 Despite the Euro having something in the Gulf late, ironically the crazy GFS has no Gulf TC on its 6Z for the 1st run since way back at 18Z of 9/14! It just has one moving just N of Cuba (not in Gulf) at 384.

41 minutes ago, Windspeed said:

Lol at tonight's GFS 00z operational. I made a post during the previous week that modeling of any potential CAG system was going to be rather chaotic until something actually resolved. That has definitely been the case. Still, if something develops and gets in the right position at the right time, potential exists for a powerful system given the potential favorable upper environment that should evolve over the GOM next week. If nothing else, it's something to watch. Mind you, though the UKMet and GFS suites continue flirting with a system, the Euro suites haven't been bothered yet. I should add it's not that Euro doesn't have the CAG there, it just transfers that energy or resulting vorticity into the EPAC instead of trying to resolve something in the WCARIB or GOM.

The off again, on again UKMET is now off again with a Gulf TC fwiw.

5th CFSv2 AAM run in a row with an extreme/historic level of 4+ being progged starting Sep 19th! It looks like it’s going to actually happen, folks! My inner weenie is genuinely excited:

2 hours ago, michsnowfreak said:

Any idea the strength of the 1925-26 Nino?

Per Eric Webb’s table, 1925-6 trimonthlies peaked at +1.3.

 The E US heat of Sept 2026 is somewhat similar to the intense E US heat of another El Niño Sept, that of record breaking 1925.

38 minutes ago, ORH_wxman said:

Prob safe to call the extent min now too....about a 130k increase in the last two days as rapid refreezing is occurring in the high central arctic basin. 

 

So it looks like the final minimums this year will be 2.711 million sq km on NSIDC area and 4.574 million sqkm on NSIDC extent. 

This chart agrees with your data that the minimum has passed due to increases during the last week: 2026 is now back to ~175K sq km above the 2013-24 avg for Sept 15th, which is the best in relation to that avg in about a month. It’s now per this chart >800K higher than it was on 9/15/2020! 2020 didn’t reach yesterday’s level til ~Oct 5th! The cold Arctic N of 80N during summer very likely helped:

On 9/14/2026 at 6:07 AM, olafminesaw said:

Could be flirting with the warmest September on record at GSO

Thanks. I agree 100% with the above analysis as of Sept 13th MTD suggesting Sept of 2026 at GSO would (assuming the model projection is in the ballpark of reality of course) obliterate 2019’s 76.4F! Update: Sept 1-15 is at 80.0, which is consistent with the graph.

But FYI regarding GSO’s warmest Septembers on record:

1921 at 78.2 and 1925 at 77.9 were warmer than 3rd place’s 2019 at 76.4.

 Even so: if I look at projections for these projections for the 2nd half of September and assuming they’re in the ballpark of reality, GSO would even be flirting with 1921’s 78.2! The projection I ran was 78.1, which would obliterate 2019’s 76.4.

https://www.weather.gov/wrh/Climate?wfo=rah

22 hours ago, GaWx said:

What’s this on the 12Z UKMET? For the first time, it has a TC (TD) in the C Gulf late in the run with it moving slowly WNW and strengthening:

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 150 HOURS
FORECAST POSITION AT T+150 : 25.0N 90.7W

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
0000UTC 22.09.2026 156 25.0N 90.4W 1008 23
1200UTC 22.09.2026 168 25.5N 91.7W 1005 31

After having a central Gulf TD late on yesterday’s 12Z per the quoted post and then not on the 0Z, today’s 12Z UKMET at the identical time (18Z on 9/21) has a TD form albeit in the E Gulf rather than C Gulf and with it moving very slowly WNW just like yesterday’s run had:

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 126 HOURS
FORECAST POSITION AT T+126 : 26.8N 84.1W

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
0000UTC 22.09.2026 132 26.6N 84.0W 1008 21
1200UTC 22.09.2026 144 27.0N 84.7W 1008 20
0000UTC 23.09.2026 156 27.1N 84.7W 1008 25
1200UTC 23.09.2026 168 27.2N 85.4W 1006 31

10 hours ago, GaWx said:

Latest (0Z of Sep 15th) CFSv2 AAM forecast, which is already at a very high >+3, is like yesterday progging an off the charts extreme/historic? +4+ starting by Sep 19th (earliest in the forecast I’ve ever seen) and lasting at least through Sep 24th:

9/15 12Z CFSv2 consistent with 0Z run having AAM on Sep 19th go to a historical extreme level (+4+):

38 minutes ago, Stormchaserchuck1 said:

Are we really getting such a large 500mb ridge? Surface temps aren't as impressive as H5. That's actually not too far away from the all time US record. I wonder if we are shattering mid-Sept US record?

Chuck,

 I’m thinking that the reason the 2m anomalies aren’t as impressive as the H5 anomalies is probably that there’s a lot of Atlantic origin moist and cooler air in the 2m mix as opposed to drier and hotter land based air.

 Opinions?

What’s this on the 12Z UKMET? For the first time, it has a TC (TD) in the C Gulf late in the run with it moving slowly WNW and strengthening:

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 150 HOURS
FORECAST POSITION AT T+150 : 25.0N 90.7W

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
0000UTC 22.09.2026 156 25.0N 90.4W 1008 23
1200UTC 22.09.2026 168 25.5N 91.7W 1005 31

Check out this insanity: the latest 3 day mean CFSv2 has not just the most negative H5 anomalies of DJFM in March but even the absolutes are the most negative! And it’s been that way on a good # of 3 day means!

Dec: highest H5 absolutes and anomalies of DJFM:

March: lowest H5 absolutes and anomalies of DJFM as they steadily cool from Dec to March!

 The absolutes for March are 5-15 dm lower than that for Dec over most of the E US! Does this look reasonable? The 2m absolutes aren’t the coldest though although they’re not far off in some portions. I couldn’t find a Nino with the coldest absolutes of the winter in March though I found many with a solidly cold March.
 
 The only winters on record with the coldest absolutes of NDJFM being March in the E US overall are 1890, 1932, and 1960 (all non-Nino). I guess we’re due fwiw.

38 minutes ago, OSUmetstud said:

Compare these to Sep ‘26 warmest JAMSTEC peak period (OND) SSTa longitude of 120-125W, which is between Euro’s 110W and CANSIPS’ 145W. It will be interesting to see which verifies the closest. Do you have a prediction for the warmest longitude at the progged OND peak? Between these 3 model progs, Euro 110W, JAMSTEC 120-125W, and CANSIPS 145W, which do you think will end up the closest?

Latest (0Z of Sep 15th) CFSv2 AAM forecast, which is already at a very high >+3, is like yesterday progging an off the charts extreme/historic? +4+ starting by Sep 19th (earliest in the forecast I’ve ever seen) and lasting at least through Sep 24th:

JAMSTEC Sept ‘26 Nino 3.4 forecast (this is NOT relative): mean is stronger than recent CFSv2 (though CFSv2 updates more recent since their updates are much more frequent) and mean cools more slowly, too, especially into Jan:

^How well did Jamstec’s May forecast for JJA verify in the CONUS?

May ‘26 Jamstec forecast for summer ‘26:

Actual for summer ‘26: Jamstec forecast excellent in E US; overall CONUS pattern excellent with warmest in SW US and coolest Midwest although it wasn’t quite warm enough in sone of the SW US:

 Here’s my analysis of the new Jamstec forecast for winter: hint SE cold lovers will enjoy this as it is progging the coldest winter in the SE/Mid-South since 2014-5!

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/