November 2025 OBS Discussion

[Wannabehippie]

On 11/21/2025 at 1:41 PM, eduggs said:

It responded that it didn't use any papers.

My earlier responses were based on:

• foundational meteorological knowledge (jet dynamics, cutoff-low behavior, coastal steering, ENSO teleconnections, North Pacific climatology),

• plus the real-time information I retrieved via your previous queries.

Keep in mind that chatGTP is not the be all and end all of accuracy. it is only as good as the search terms, and what is inputted in to it. Too many variables at this point with it IMHO.

 

[Sundog]

Do you know how hard it is for the EPS to show such a negative anomaly in the long range with our background state?

[cleetussnow]

53 minutes ago, Sundog said:

Do you know how hard it is for the EPS to show such a negative anomaly in the long range with our background state?

Not hard. Thats just a picture at this time horizon.  Artwork.  We see these model phantoms a lot, due to said background state.  

[psv88]

0.28 from the rain. 
 

looking forward to some sunny skies 

[the_other_guy]

27F, coldest thus far…and unexpected

[bluewave]

I guess it will be fitting that Thanksgiving is set to follow the same windy pattern we have seen all year. Mild Great Lakes cutter storm track on Wednesday. Then strong W to NW flow on Thursday.

The one hope is that the strongest winds of around 40 mph peak after parade time. But you can see this year already has double the number of 40 mph gust days as any previous year at over 60.

Most of the gusts since January have occurred behind Great Lakes or hugger storm tracks on W to NW flow. The one lone coastal storm back in October was one of the few days with a NE gust over 40 mph. 
 

 

[qg_omega]

38 minutes ago, bluewave said:

I guess it will be fitting that Thanksgiving is set to follow the same windy pattern we have seen all year. Mild Great Lakes cutter storm track on Wednesday. Then strong W to NW flow on Thursday.

The one hope is that the strongest winds of around 40 mph peak after parade time. But you can see this year already has double the number of 40 mph gust days as any previous year at over 60.

Most of the gusts since January have occurred behind Great Lakes or hugger storm tracks on W to NW flow. The one lone coastal storm back in October was one of the few days with a NE gust over 40 mph. 
 

 

Pattern is locked in with no signs of changes

[bluewave]

14 minutes ago, qg_omega said:

Pattern is locked in with no signs of changes

Record WPAC warm pool in conjunction with the cold over Siberia continue to create the very strong thermal gradient leading to the faster Pacific Jet and dominant Northern Stream Storm track.

The tropical warm pool near the equator and the record subtropical warm pool to the east of Japan and south of the Aleutians both enhance the Southeast ridge. Plus the record Gulf Stream SSTs also contribute.

Models tend to underestimate this long range influence as we are seeing with the new forecasts in early December with stronger Southeast ridge than originally forecast. Once this pattern becomes established, it can linger longer than expected as we have often seen heading into December over the last decade. 
 

New EPS forecast for December 1-8

Old EPS forecast December 1-8

 

[MJO812]

21 minutes ago, qg_omega said:

Pattern is locked in with no signs of changes

Yes right now but it shouldn't last. 

Delayed but not denied 

[bluewave]

21 minutes ago, MJO812 said:

Yes right now but it shouldn't last. 

Delayed but not denied 

The long range EPS keeps underestimating that forcing in the 120E to 150E Maritime Continent regions.

New run

 

Old run

[susqushawn]

15 minutes ago, bluewave said:

Record WPAC warm pool in conjunction with the cold over Siberia continue to create the very strong thermal gradient leading to the faster Pacific Jet and dominant Northern Stream Storm track.

The tropical warm pool near the equator and the record subtropical warm pool to the east of Japan and south of the Aleutians both enhance the Southeast ridge. Plus the record Gulf Stream SSTs also contribute.

Models tend to underestimate this long range influence as we are seeing with the new forecasts in early December with stronger Southeast ridge than originally forecast. Once this pattern becomes established, it can linger longer than expected as we have often seen heading into December over the last decade. 
 

New EPS forecast for December 1-8

Old EPS forecast December 1-8

 

Long range ensemble guidance has also routinely undersold the +PNA the last few months, this example of course flips that script

[MJO812]

Larry Cosgrove thinks December will be mild and January and February will be colder.

I haven't heard anyone say that expect him. All I have been hearing and seeing are  cold and active December forecasts due to the PV.

[wdrag]

Saw the prior 24 hours of posts... and suggests but not locked into a Wind Advy thread Fri 11/28, possibly starting Thanksgiving afternoon.  Awaiting 12z/24 (Monday) modeling.