November Medium/Long Range Discussion

[WinstonSalemArlington]

4 minutes ago, JenkinsJinkies said:

Wait, cold and wet, in a Niña?

Weak Niña?

[Eskimo Joe]

13 minutes ago, JenkinsJinkies said:

Wait, cold and wet, in a Niña?

Seeing the slightly above normal precip anomaly doesn't surprise me given the H5 look in the quote post. You have a boundary pressing south and we're right on the edge. It's possible some light rail tracks could be hinted at by guidance.

[WxUSAF]

Another good thread from @griteater. 2017 was the last year we had even respectable December snowfall. 

[Bob Chill]

The weeklies H5 that Will posted is pretty ideal for small/moderate events. I dont really like big downhill/uphill patterns. Potential for bigger storms is better but lots of waiting and high risk of things not turning the corner in the right spot. The broader trough can be more active and shortwaves can get going much further west with good trajectory for the MA. TN Valley overrunners and things like that.  

In dec, big amplified stuff can often have temp problems too. Atlantic air moisture draw isnt nearly as friendly as Jan/Feb. Entrenched cold overrunning is easier to produce in Dec 

[WEATHER53]

33 minutes ago, WxUSAF said:

Another good thread from @griteater. 2017 was the last year we had even respectable December snowfall. 

I got 89-90 also and 95-96. It’s interesting this season that a lot of occurred event analogs from this  year are matching to positive outcome producing years in the past 

[LongRanger]

I like seeing juicy Pacific systems come ashore near LA, as is progged for this weekend. When other conditions are right, those have produced some of our biggest snows about a week later. May that pattern continue into the coming colder months.

[Eskimo Joe]

57 minutes ago, Bob Chill said:

The weeklies H5 that Will posted is pretty ideal for small/moderate events. I dont really like big downhill/uphill patterns. Potential for bigger storms is better but lots of waiting and high risk of things not turning the corner in the right spot. The broader trough can be more active and shortwaves can get going much further west with good trajectory for the MA. TN Valley overrunners and things like that.  

In dec, big amplified stuff can often have temp problems too. Atlantic air moisture draw isnt nearly as friendly as Jan/Feb. Entrenched cold overrunning is easier to produce in Dec 

Agreed. Let's lock in with light to mod.ecent one after the other. Don't blow a good pattern on one big storm that melts off in a few days, especially leading into Christmas.

[psuhoffman]

1 hour ago, Bob Chill said:

The weeklies H5 that Will posted is pretty ideal for small/moderate events. I dont really like big downhill/uphill patterns. Potential for bigger storms is better but lots of waiting and high risk of things not turning the corner in the right spot. The broader trough can be more active and shortwaves can get going much further west with good trajectory for the MA. TN Valley overrunners and things like that.  

In dec, big amplified stuff can often have temp problems too. Atlantic air moisture draw isnt nearly as friendly as Jan/Feb. Entrenched cold overrunning is easier to produce in Dec 

Historically I don’t disagree. But we’ve said this quite a few times over the last 10 years and it seems our “hit rate” has become pretty low in a more zonal suppressed “big bowl” pattern also, to the point maybe it’s better to just take our chances on the big hit anymore. But since we don’t control what we get it doesn’t matter.   Yea I’d take a high chance if getting some moderate 3-5” type events over a very low chance at a 10”+ but it doesn’t seem to be that way anymore. We seem to waste the “high probability” looks just as often as the big hit ones lately. 

[Weather Will]

14 minutes ago, psuhoffman said:

Historically I don’t disagree. But we’ve said this quite a few times over the last 10 years and it seems our “hit rate” has become pretty low in a more zonal suppressed “big bowl” pattern also, to the point maybe it’s better to just take our chances on the big hit anymore. But since we don’t control what we get it doesn’t matter.   Yea I’d take a high chance if getting some moderate 3-5” type events over a very low chance at a 10”+ but it doesn’t seem to be that way anymore. We seem to waste the “high probability” looks just as often as the big hit ones lately. 

I get it, but let's try to keep the vibes positive this winter, at least it is not a shut the blinds look....maybe we will get lucky...

[Stormchaserchuck1]

Problem really is that we need a big NE N. Pacific low pressure, major negative anomaly at 500mb, and we haven't really had that since the 15-16 Strong Nino. I think maybe 1 or 2 anomalous times of only a few weeks in the Winter since then, but that's it. It's really a drought - actually the Feb-March N. Pacific -PNA recently broke the previous record for a 8-year consecutive period by +140%. We've been needing a big N. Pacific pattern change. We want the jet stream to be stopped up, and a big part of that is NE N. Pacific low pressure. It's not climate change, unless you are saying CC is putting more High pressure in the north pacific ocean. It's been a Hadley Cell - La Nina pattern since 16-17 (but to a lesser extent since 98-99).  

[bncho]

Do not fear, guys! This year isn't a shut the blinds look. Plus, if all else fails, we have the 26-27 +PDO Nino open the blinds look!

[Stormchaserchuck1]

I wouldn't be so sure about +PDO in 2026, this is what we've seen so far this decade, which is way more extreme than any decade on record:

October 2025	-2.40
September 2025	-2.33
August 2025	-3.20
July 2025	-4.16
June 2025	-2.62
May 2025	-1.66
April 2025	-1.15
March 2025	-1.12
February 2025	-1.40
January 2025	-1.28
December 2024	-2.03
November 2024	-3.13
October 2024	-3.80
September 2024	-3.56
August 2024	-2.91
July 2024	-3.00
June 2024	-3.15
May 2024	-2.98
April 2024	-2.11
March 2024	-1.52
February 2024	-1.33
January 2024	-1.57
December 2023	-1.66
November 2023	-1.79
October 2023	-2.23
September 2023	-2.99
August 2023	-2.47
July 2023	-2.52
June 2023	-2.53
May 2023	-2.42
April 2023	-3.07
March 2023	-2.45
February 2023	-1.65
January 2023	-1.24
December 2022	-2.21
November 2022	-2.41
October 2022	-1.81
September 2022	-2.29
August 2022	-2.38
July 2022	-2.64
June 2022	-1.32
May 2022	-2.24
April 2022	-2.09
March 2022	-1.67
February 2022	-1.91
January 2022	-2.40
December 2021	-2.71
November 2021	-2.75
October 2021	-3.13
September 2021	-1.96
August 2021	-0.95
July 2021	-2.00
June 2021	-1.82
May 2021	-2.04
April 2021	-1.84
March 2021	-1.67
February 2021	-1.09
January 2021	-0.61
December 2020	-0.99
November 2020	-1.58
October 2020	-0.62
September 2020	-1.04
August 2020	-1.33
July 2020	-0.92
June 2020	-0.75
May 2020	-0.53
April 2020	-1.32
March 2020	-1.75
February 2020	-1.48
January 2020	-1.41

Even seasonal models have a -PDO next Winter, despite El Nino.. but it's far out so skill is low.

[mitchnick]

12 minutes ago, Stormchaserchuck1 said:

I wouldn't be so sure about +PDO in 2026, this is what we've seen so far this decade, which is way more extreme than any decade on record:

October 2025	-2.40
September 2025	-2.33
August 2025	-3.20
July 2025	-4.16
June 2025	-2.62
May 2025	-1.66
April 2025	-1.15
March 2025	-1.12
February 2025	-1.40
January 2025	-1.28
December 2024	-2.03
November 2024	-3.13
October 2024	-3.80
September 2024	-3.56
August 2024	-2.91
July 2024	-3.00
June 2024	-3.15
May 2024	-2.98
April 2024	-2.11
March 2024	-1.52
February 2024	-1.33
January 2024	-1.57
December 2023	-1.66
November 2023	-1.79
October 2023	-2.23
September 2023	-2.99
August 2023	-2.47
July 2023	-2.52
June 2023	-2.53
May 2023	-2.42
April 2023	-3.07
March 2023	-2.45
February 2023	-1.65
January 2023	-1.24
December 2022	-2.21
November 2022	-2.41
October 2022	-1.81
September 2022	-2.29
August 2022	-2.38
July 2022	-2.64
June 2022	-1.32
May 2022	-2.24
April 2022	-2.09
March 2022	-1.67
February 2022	-1.91
January 2022	-2.40
December 2021	-2.71
November 2021	-2.75
October 2021	-3.13
September 2021	-1.96
August 2021	-0.95
July 2021	-2.00
June 2021	-1.82
May 2021	-2.04
April 2021	-1.84
March 2021	-1.67
February 2021	-1.09
January 2021	-0.61
December 2020	-0.99
November 2020	-1.58
October 2020	-0.62
September 2020	-1.04
August 2020	-1.33
July 2020	-0.92
June 2020	-0.75
May 2020	-0.53
April 2020	-1.32
March 2020	-1.75
February 2020	-1.48
January 2020	-1.41

Even seasonal models have a -PDO next Winter, despite El Nino.. but it's far out so skill is low.

Just multiply those numbers by -1 and voila!

[psuhoffman]

14 minutes ago, Stormchaserchuck1 said:

I wouldn't be so sure about +PDO in 2026, this is what we've seen so far this decade, which is way more extreme than any decade on record:

October 2025	-2.40
September 2025	-2.33
August 2025	-3.20
July 2025	-4.16
June 2025	-2.62
May 2025	-1.66
April 2025	-1.15
March 2025	-1.12
February 2025	-1.40
January 2025	-1.28
December 2024	-2.03
November 2024	-3.13
October 2024	-3.80
September 2024	-3.56
August 2024	-2.91
July 2024	-3.00
June 2024	-3.15
May 2024	-2.98
April 2024	-2.11
March 2024	-1.52
February 2024	-1.33
January 2024	-1.57
December 2023	-1.66
November 2023	-1.79
October 2023	-2.23
September 2023	-2.99
August 2023	-2.47
July 2023	-2.52
June 2023	-2.53
May 2023	-2.42
April 2023	-3.07
March 2023	-2.45
February 2023	-1.65
January 2023	-1.24
December 2022	-2.21
November 2022	-2.41
October 2022	-1.81
September 2022	-2.29
August 2022	-2.38
July 2022	-2.64
June 2022	-1.32
May 2022	-2.24
April 2022	-2.09
March 2022	-1.67
February 2022	-1.91
January 2022	-2.40
December 2021	-2.71
November 2021	-2.75
October 2021	-3.13
September 2021	-1.96
August 2021	-0.95
July 2021	-2.00
June 2021	-1.82
May 2021	-2.04
April 2021	-1.84
March 2021	-1.67
February 2021	-1.09
January 2021	-0.61
December 2020	-0.99
November 2020	-1.58
October 2020	-0.62
September 2020	-1.04
August 2020	-1.33
July 2020	-0.92
June 2020	-0.75
May 2020	-0.53
April 2020	-1.32
March 2020	-1.75
February 2020	-1.48
January 2020	-1.41

Even seasonal models have a -PDO next Winter, despite El Nino.. but it's far out so skill is low.

Yes.  But that can’t continue forever. Look at all the past similar extremely negative PDO periods. There longest such recorded periods and closest to this one were in the 1950s and 1970s. But those didn’t extend past 6 or 7 years. The extreme -PDO. So we have to be coming to the end of this current cycle soon. There is absolutely no precedent for this continuing much longer. 

[psuhoffman]

45 minutes ago, Weather Will said:

I get it, but let's try to keep the vibes positive this winter, at least it is not a shut the blinds look....maybe we will get lucky...

 

[George001]

30 minutes ago, Stormchaserchuck1 said:

I wouldn't be so sure about +PDO in 2026, this is what we've seen so far this decade, which is way more extreme than any decade on record:

October 2025	-2.40
September 2025	-2.33
August 2025	-3.20
July 2025	-4.16
June 2025	-2.62
May 2025	-1.66
April 2025	-1.15
March 2025	-1.12
February 2025	-1.40
January 2025	-1.28
December 2024	-2.03
November 2024	-3.13
October 2024	-3.80
September 2024	-3.56
August 2024	-2.91
July 2024	-3.00
June 2024	-3.15
May 2024	-2.98
April 2024	-2.11
March 2024	-1.52
February 2024	-1.33
January 2024	-1.57
December 2023	-1.66
November 2023	-1.79
October 2023	-2.23
September 2023	-2.99
August 2023	-2.47
July 2023	-2.52
June 2023	-2.53
May 2023	-2.42
April 2023	-3.07
March 2023	-2.45
February 2023	-1.65
January 2023	-1.24
December 2022	-2.21
November 2022	-2.41
October 2022	-1.81
September 2022	-2.29
August 2022	-2.38
July 2022	-2.64
June 2022	-1.32
May 2022	-2.24
April 2022	-2.09
March 2022	-1.67
February 2022	-1.91
January 2022	-2.40
December 2021	-2.71
November 2021	-2.75
October 2021	-3.13
September 2021	-1.96
August 2021	-0.95
July 2021	-2.00
June 2021	-1.82
May 2021	-2.04
April 2021	-1.84
March 2021	-1.67
February 2021	-1.09
January 2021	-0.61
December 2020	-0.99
November 2020	-1.58
October 2020	-0.62
September 2020	-1.04
August 2020	-1.33
July 2020	-0.92
June 2020	-0.75
May 2020	-0.53
April 2020	-1.32
March 2020	-1.75
February 2020	-1.48
January 2020	-1.41

Even seasonal models have a -PDO next Winter, despite El Nino.. but it's far out so skill is low.

I’m not sold on El Niño either. Historically year 2 after a strong/super mini goes cold ENSO, year 3 is roughly 50/50 and its year 4 that tilts warm ENSO. 

[Stormchaserchuck1]

14 minutes ago, George001 said:

I’m not sold on El Niño either. Historically year 2 after a strong/super mini goes cold ENSO, year 3 is roughly 50/50 and its year 4 that tilts warm ENSO. 

Yeah but after 5/6 La Nina years, we have a tendency to flip for the next 3-5 years, and that happens immediately after 4/6 consecutive ENSO events or greater.. I'd give it 2/3 chances for El Nino next year, even if it's weak.. 

[Maestrobjwa]

15 minutes ago, George001 said:

I’m not sold on El Niño either. Historically year 2 after a strong/super mini goes cold ENSO, year 3 is roughly 50/50 and its year 4 that tilts warm ENSO. 

Wut. Man it's too hard to get a Nino it takes forever! Or does a -PDO regime naturally produce more ninas?

[Stormchaserchuck1]

34 minutes ago, psuhoffman said:

Yes.  But that can’t continue forever. Look at all the past similar extremely negative PDO periods. There longest such recorded periods and closest to this one were in the 1950s and 1970s. But those didn’t extend past 6 or 7 years. The extreme -PDO. So we have to be coming to the end of this current cycle soon. There is absolutely no precedent for this continuing much longer. 

Kind of limited data. History does say the average PDO cycle is just about as long as we've been in since 1998, but we seem to be at the most extreme part of the cycle now and common sense says that's probably another 10-15 years to neutralize. I know the NOAA has been doing subsurface passes in the PDO area, and there is warmer water down to -200m now more than ever before, which could be 5-10 years to change phases cleanly.  There are sometimes 2-3 year phases blips in a long term opposite phase though. 

[Steve25]

2 hours ago, WxUSAF said:

Another good thread from @griteater. 2017 was the last year we had even respectable December snowfall. 

Someone can correct me if I’m wrong, but the end of December 2017 into January 2018 was one of the coldest stretches I can remember in recent history. I recall there was like a 10 day stretch where it didn’t get above freezing in Baltimore. Many nights in the single digits, many days that struggled to get out of the low 20s. 

[psuhoffman]

14 minutes ago, Stormchaserchuck1 said:

Kind of limited data. History does say the average PDO cycle is just about as long as we've been in since 1998, but we seem to be at the most extreme part of the cycle now and common sense says that's probably another 10-15 years to neutralize. I know the NOAA has been doing subsurface passes in the PDO area, and there is warmer water down to -200m now more than ever before, which could be 5-10 years to change phases cleanly.  There are sometimes 2-3 year phases blips in a long term opposite phase though. 

I’m not talking about the longer scale -PDO. Within that are shorter term extreme phases. That’s what’s been killing is. We can snow in a somewhat negative PDO. Look at the 1960s!  But past mini extreme -PDO periods (typically 4-7 years where the PDO is below -1 most of the time) are always god awful for snowfall. We have to be coming to the end of this mini super negative PDO phase. None going back 125 years last longer than about 6-7 years. 

[wxdude64]

27 minutes ago, Steve25 said:

Someone can correct me if I’m wrong, but the end of December 2017 into January 2018 was one of the coldest stretches I can remember in recent history. I recall there was like a 10 day stretch where it didn’t get above freezing in Baltimore. Many nights in the single digits, many days that struggled to get out of the low 20s. 

I set 8 new either record lows or 'cool maxes' between 1/292017 and 1/9/2018, lowest temp was -2.8 degrees. Warmest was 32.8 degrees. Below 20 degrees for 79 hours between 1/5 and 1/8.

[frd]

36 minutes ago, Steve25 said:

Someone can correct me if I’m wrong, but the end of December 2017 into January 2018 was one of the coldest stretches I can remember in recent history. I recall there was like a 10 day stretch where it didn’t get above freezing in Baltimore. Many nights in the single digits, many days that struggled to get out of the low 20s. 

There was also this 

Rehoboth Beach experienced a significant blizzard and "bomb cyclone" on January 4, 2018, which brought heavy snow, strong winds, and whiteout conditions. The storm resulted in a blizzard warning for Sussex County, an estimated 8 to 12 inches of snow, and a Level 1 driving warning issued by the Governor. 

 

[Chris78]

37 minutes ago, psuhoffman said:

I’m not talking about the longer scale -PDO. Within that are shorter term extreme phases. That’s what’s been killing is. We can snow in a somewhat negative PDO. Look at the 1960s!  But past mini extreme -PDO periods (typically 4-7 years where the PDO is below -1 most of the time) are always god awful for snowfall. We have to be coming to the end of this mini super negative PDO phase. None going back 125 years last longer than about 6-7 years. 

What year did we start into this extremely negative PDO cycle?

[cbmclean]

1 hour ago, Steve25 said:

Someone can correct me if I’m wrong, but the end of December 2017 into January 2018 was one of the coldest stretches I can remember in recent history. I recall there was like a 10 day stretch where it didn’t get above freezing in Baltimore. Many nights in the single digits, many days that struggled to get out of the low 20s. 

That was a historic cold period in Eastern NC.  RDU set a record for most consecutive hours below freezing.  A pond at a park near my house froze over, which I had never seen in my life before.  My PWS recorded 0 °F, and there was shore fast ice at the Outer Banks.  Crazy times.  

[psuhoffman]

28 minutes ago, Chris78 said:

What year did we start into this extremely negative PDO cycle?

2019 following the weak nino 

[WEATHER53]

3 hours ago, wxdude64 said:

I set 8 new either record lows or 'cool maxes' between 1/292017 and 1/9/2018, lowest temp was -2.8 degrees. Warmest was 32.8 degrees. Below 20 degrees for 79 hours between 1/5 and 1/8.

Didn’t BWI hit 17 for a high 3 consecutive days?

[Stormchaserchuck1]

Good news and bad news 

The bad news is, models took away the prolonged/sustained west-based -NAO that it had been showing, the last few runs. 

The good news is, around the turn of the month they are developing a strong -WPO pattern with +PNA underneath of it -- a Pacific based cold pattern that should put much of the CONUS below average to start off December

0z GEFS mean hr384

[Jebman]

7 hours ago, Weather Will said:

I get it, but let's try to keep the vibes positive this winter, at least it is not a shut the blinds look....maybe we will get lucky...

You WILL get lucky!!

[psuhoffman]

6 hours ago, Stormchaserchuck1 said:

Good news and bad news 

The bad news is, models took away the prolonged/sustained west-based -NAO that it had been showing, the last few runs. 

The good news is, around the turn of the month they are developing a strong -WPO pattern with +PNA underneath of it -- a Pacific based cold pattern that should put much of the CONUS below average to start off December

0z GEFS mean hr384

That’s more important to snow around here in December than the NAO