Winter 2024-25 Discussion/Speculation

[JenkinsJinkies]

47 minutes ago, psuhoffman said:

Except from 2000-2020 while north of us was setting records left and right we were actually slightly below avg (old averages anyways) for the period. Our snow climo was already degrading even during the favorable pattern we were in during that period. 

I wonder if 2003, 2009/10, and 2016 masked that to the untrained observer?

[psuhoffman]

3 hours ago, JenkinsJinkies said:

I wonder if 2003, 2009/10, and 2016 masked that to the untrained observer?

I believe so. Precipitation events are also increasing so when we do get a rare snowy year they can be big.  Not only is our mean and median dropping but variance is increasing. From 1996 to 2016 we were getting more 10”+ snowstorms even while getting less snow overall!  We were getting some of our snowiest winters while getting less snow overall. The big red flag to me was that places that used to be correlated to our snow decoupled. NYC started getting a lot of above avg snow seasons while we were below. There started to be a very sharp cutoff just to our north. Kinda like used to happen just to our south!  I mean even in a snowy winter at some point you’re just too far south for it to matter. IMO that line was shifting north on average.  
 

Because we use current averages as a baseline it masks this some because we’ve already lost a significant % of our snow climo. I think this is the best way to illustrate it. 
 

From 1996-2016 the mean pattern was this!

look at that. Over 21 years that was the average base pattern. 
 

But at DCA only 6 years of the 21 were above avg snow! And this was the averages at the 3 reporting stations

DCA: 15.9” IAD: 23.7”. BWI: 22.9”

Now if we compare that to what’s happened since that looks like snow Valhalla. But the 30 year mean at all 3 airports going into that period was 18.5”, 23.6” and 22.3” 

The mean avg across all 3 stations going into 1996 was 21.5” but from 1996 to 2016 with the best possible long term cycle we could hope for the seasonal avg was 20.9”.  The mean avg snowfall across the area was actually slightly less during those 21 years than the 30 years before despite being what should have been a very snowy period which was very snowy…just to our north!  
 

I think the “you’re too far south for the pattern to matter” line has been shifting north for a while and even once the pattern gets better there is a chance on some years it’s still to our north. 
 

 

 

[Eskimo Joe]

Just give me climo snowfall with -1 temps for the seasonal and I'll consider it a win.

[Terpeast]

52 minutes ago, Eskimo Joe said:

Just give me climo snowfall with +2 temps for the seasonal and I'll consider it a win.

Fixed

[psuhoffman]

1 hour ago, Eskimo Joe said:

Just give me climo snowfall with -1 temps for the seasonal and I'll consider it a win.

But what do you consider "climo"?  When I moved to northern VA in 1993 IAD's "climo" was 24".  If we continue to get similar results the rest of this decade to what we've had recently the new "climo" would be around 17".  The problem is during a shifting climate a 30 year mean is always behind the curve.  Same with temps...at the rate we are warming it is incredibly difficult to get an extended stretch of "below normal" because the normals we are using are already out dated and the new baseline status quo has warmed. 

[Eskimo Joe]

3 minutes ago, psuhoffman said:

But what do you consider "climo"?  When I moved to northern VA in 1993 IAD's "climo" was 24".  If we continue to get similar results the rest of this decade to what we've had recently the new "climo" would be around 17".  The problem is during a shifting climate a 30 year mean is always behind the curve.  Same with temps...at the rate we are warming it is incredibly difficult to get an extended stretch of "below normal" because the normals we are using are already out dated and the new baseline status quo has warmed. 

Climo snowfall for my location is 23 inches. Just give me that. I have only experience 2 warning level snow storms since moving back to Maryland in August 2016.

[psuhoffman]

@Eskimo Joe  One last thing, more than once it's been asked "are big years like 2010 masking the true extent of the degradation some" and that is a subjective thing...depends on perspective.  But variance is increasing, and the probabilities of a single digit snowfall season have gone up exponentially in the last 30 years.  But maybe the best way to look at it is since 2000 IAD's average snowfall is 19".  That's bad, and well below the normal of around 24" before that.  But if we take out just 3 seasons, 2003, 2010, and 2014, the average is only 13" which is must more indicative of what we are likely to get in any given year that the 19" which is incredibly skewed by those 3 huge years in the last 23 seasons.  What happened in the 20/23 is much more "what we should expect" in any given year.  In past periods there wasn't as big a gap between the mean and median snowfall.  But it could be argued that we are using both outdated and unrealistic expectations for what "normal" snowfall is around here now.  Truth is "normal" is probably closer to 8-15" area wide than the numbers most of us have in our head.  

[WxUSAF]

The “good” Ninas recently IMBY are 15-20”. So I won’t complain much if we get to that range. Above 20” in a Niña would be solid. Of course the bad Nina’s are really bad…

[Eskimo Joe]

12 minutes ago, psuhoffman said:

@Eskimo Joe  One last thing, more than once it's been asked "are big years like 2010 masking the true extent of the degradation some" and that is a subjective thing...depends on perspective.  But variance is increasing, and the probabilities of a single digit snowfall season have gone up exponentially in the last 30 years.  But maybe the best way to look at it is since 2000 IAD's average snowfall is 19".  That's bad, and well below the normal of around 24" before that.  But if we take out just 3 seasons, 2003, 2010, and 2014, the average is only 13" which is must more indicative of what we are likely to get in any given year that the 19" which is incredibly skewed by those 3 huge years in the last 23 seasons.  What happened in the 20/23 is much more "what we should expect" in any given year.  In past periods there wasn't as big a gap between the mean and median snowfall.  But it could be argued that we are using both outdated and unrealistic expectations for what "normal" snowfall is around here now.  Truth is "normal" is probably closer to 8-15" area wide than the numbers most of us have in our head.  

I fully expect no snow this year and 65 and sunny on Christmas. Our winters are more like North Carolina now. It's just pathetic.

[psuhoffman]

17 minutes ago, WxUSAF said:

The “good” Ninas recently IMBY are 15-20”. So I won’t complain much if we get to that range. Above 20” in a Niña would be solid. Of course the bad Nina’s are really bad…

That checks out, if I get to 30" up here I will do cartwheels, and that's probably about the same % of "climo" as 15-20" for your area.  Frankly if you offered me 25" right now, take it or leave it, I would take it and run.  That would be unthinkable 10 years ago, but I am scarred and shell shocked by the frequency of total dud winters even up here recently.  

[CAPE]

Winters are still good even with little snow because it is a break from the relentless heat and humidity and bugs of our long Summer. Early Fall has been better than usual so far temp wise. If it is a typical Nina winter we will have plenty of dry days for hiking, getting outside projects done, etc. Everyone here should have downward adjusted snowfall expectations at this juncture.

[psuhoffman]

36 minutes ago, WxUSAF said:

Of course the bad Nina’s are really bad…

I wonder if we actually want a stronger nina given the options.  There have been 2 examples of an enso neutral DJF following a nina during this recent pacific cycle, 2017 and 2020, and both were total dud winters.  And the weakest actual Nina DJF we've had was the other total dud winter 2023.  The stronger Ninas were actually significantly better.  I see a lot of people that seem to be rooting against the nina in the enso thread but if we want snow I'm not sure that's really wise.  

[Maestrobjwa]

10 minutes ago, psuhoffman said:

I wonder if we actually want a stronger nina given the options.  There have been 2 examples of an enso neutral DJF following a nina during this recent pacific cycle, 2017 and 2020, and both were total dud winters.  And the weakest actual Nina DJF we've had was the other total dud winter 2023.  The stronger Ninas were actually significantly better.  I see a lot of people that seem to be rooting against the nina in the enso thread but if we want snow I'm not sure that's really wise.  

I don't get why a stronger nina would be better, though...Wouldn't it just be a stronger version of what doesn't work? Lol

[Eskimo Joe]

24 minutes ago, psuhoffman said:

That checks out, if I get to 30" up here I will do cartwheels, and that's probably about the same % of "climo" as 15-20" for your area.  Frankly if you offered me 25" right now, take it or leave it, I would take it and run.  That would be unthinkable 10 years ago, but I am scarred and shell shocked by the frequency of total dud winters even up here recently.  

Same.

[psuhoffman]

11 minutes ago, Maestrobjwa said:

I don't get why a stronger nina would be better, though...Wouldn't it just be a stronger version of what doesn't work? Lol

That is totally logical and why most assume a stronger nina is worse, but the data just doesn't support that conclusion.  Even if we go back 75 years there is almost no difference wrt snowfall between a weak and a strong nina.  And recently weak nina's have been worse.  Also, the other popular myth that a fading nina will save February/March is not true, the data indicates winters where a nina fades to neutral actually has less snow in Feb/March.  

I know you are asking why, but I just don't know.  We are still talking about a small sample size, so many it is just plain luck and over a thousand years it would balance out and in the end a weaker nina is better...Kind of like we just got 5 coin flips in a row recently odds...but no one can say that for sure.  On the flip side maybe there are subtle variables that are changed by a stronger nina.  Maybe a stronger faster pacific jet is really bad at some level but if strong enough causes enough variability such that it becomes less hostile at times?  I know later in winter nina forcing actually becomes more favorable once wavelenghts shorten, so are we are less likely to get a nice ending like 1999 and 2018 in a weaker nina possibly.  

I honestly don't know, I am just going by the data.  

[osfan24]

44 minutes ago, psuhoffman said:

I wonder if we actually want a stronger nina given the options.  There have been 2 examples of an enso neutral DJF following a nina during this recent pacific cycle, 2017 and 2020, and both were total dud winters.  And the weakest actual Nina DJF we've had was the other total dud winter 2023.  The stronger Ninas were actually significantly better.  I see a lot of people that seem to be rooting against the nina in the enso thread but if we want snow I'm not sure that's really wise.  

I literally don't even know what to root for anymore because nothing seems to work. 

[WxUSAF]

If time, money, and computing resources were not factors, I’d love to do a huge ensemble experiment of climate modeling for our snowfall varying ENSO, PDO, and perhaps some other factors. My gut is that in weak Niña/neutral winters, other aspects just dominate and we just have had more bad luck with those than what “should” happen. 

[psuhoffman]

28 minutes ago, WxUSAF said:

If time, money, and computing resources were not factors, I’d love to do a huge ensemble experiment of climate modeling for our snowfall varying ENSO, PDO, and perhaps some other factors. My gut is that in weak Niña/neutral winters, other aspects just dominate and we just have had more bad luck with those than what “should” happen. 

It's too small a sample size to draw statistically significant conclusions, but just looking at the set of neutral or extremely weak nina winters over the years...it seems that perhaps they take on the flavor of the overall longer term cycles we are in.  When we were in a more snowy cold period in general they tended to be better...and when we were in a warmer/less snowy period they sucked.  If this is true...it would explain why the last few sucked.  

[psuhoffman]

50 minutes ago, osfan24 said:

I literally don't even know what to root for anymore because nothing seems to work. 

I mean what are historically "better patterns" are still producing more snow.  What little snow we've had over the last 8 years did tend to come during the periods when we had a less hostile pattern.  We have not had much luck during the "shit the blinds" patterns.  If anything we have had even less luck during those than normal...its almost impossible to luck into snow in a bad pattern now because they are so warm now.  

The problem imo is we've spend less time than normal in a "good" pattern over the last 8 years, and our results in a bad pattern went from bad to god awful no hope at snow at all due to warming so... Also perhaps the results in the good aren't "as good" but I would want to see more data on that, we've had so few legit good long lasting patterns recently its hard to say that with any confidence.  In the end we still want some combo of -AO,-NAO,-EPO,+PNA and we really need 3 out of those 4 to have a good chance at snow.  And even if we get 3/4 the 4th cant be like historically god awful or it can still offset the other 3.  That has always been true.  We just haven't had that much lately because the pacific has been stuck in a god awful phase where the PNA is killing us most of the time.  

[psuhoffman]

For reference...there is only so much variability to the pacific under this current base state and its bad, so really we are talking about just "kinda bad" v "awful" here...but this was the mean longwave pattern during the 3 snowiest winters of the last 8 years...

This was the 3 least snowy winters...

Neither of those looks good, which is why we've had no truly snowy winters lately, but the key difference in the "snowier" years was the more poleward extent of the pacific ridge shifting the trough out of western Canada some which allows more cold air transport into our area during transient periods.  The less snowy look there is just the total kiss of death with the flat pacific ridge allowing the trough to really get stuck out west and the ridge to go ape in the east and its game over on a seasonal scale!  

[WxUSAF]

^the mole poleward WPO/EPO ridge is what Webb has been talking about on Twitter. He thinks the current Pac SST pattern favors that. 

[Terpeast]

34 minutes ago, psuhoffman said:

For reference...there is only so much variability to the pacific under this current base state and its bad, so really we are talking about just "kinda bad" v "awful" here...but this was the mean longwave pattern during the 3 snowiest winters of the last 8 years...

This was the 3 least snowy winters...

Neither of those looks good, which is why we've had no truly snowy winters lately, but the key difference in the "snowier" years was the more poleward extent of the pacific ridge shifting the trough out of western Canada some which allows more cold air transport into our area during transient periods.  The less snowy look there is just the total kiss of death with the flat pacific ridge allowing the trough to really get stuck out west and the ridge to go ape in the east and its game over on a seasonal scale!  

Looking closely at the first one, we can see more of an -epo signature with the north american trough being more central. This is what happened this past January… and that was in spite of the strong nino, not because of it. That week was more of a La Nina pattern with -EPO/-NAO. 

This is the pathway to getting snow in this new normal. I also remember (if correctly) Heisy saying that if the leading wave in front of the second storm hadn’t squashed the flow too much, it could have been a much bigger storm.

This is what we want to root for in the upcoming winter. 

[psuhoffman]

42 minutes ago, Terpeast said:

 

This is the pathway to getting snow in this new normal. I also remember (if correctly) Heisy saying that if the leading wave in front of the second storm hadn’t squashed the flow too much, it could have been a much bigger storm.

This is what we want to root for in the upcoming winter. 

Yup, but while its true, that is kind of a typical issue, and has been, when the mean trough axis is always a little too far to the NW, which even in the "better" looks is still true in this base state.  Periods of high amplitude likely lead to storms cutting way to our west...and in lower amplitude we are dealing with a bunch of weaker system running the boundary interfering with one another...but that at least gives us a chance for some snow.  Big storms are going to be very hard to come by given the larger scale issues with this base state.  Best chance might be getting really lucky with a progressive wave that is simply ridiculously juiced up.  We saw that just south of DC in the Jan 2022 storm.  

[TheClimateChanger]

3 hours ago, Eskimo Joe said:

I fully expect no snow this year and 65 and sunny on Christmas. Our winters are more like North Carolina now. It's just pathetic.

True. The 9-year mean of 39.3F at BWI compares favorably to GSO's mean of 39.3F from 1933-34 to 1987-88, and the 9-year mean of 42.0F at DCA compares favorably to CLT's 1943-44 to 1987-88 mean of 42.3F and is nearly 1F warmer than RDU's 1944-45 to 1987-88 mean of 41.2F.

But it's best not to take anything for granted. These very well could be the best winters of the rest of your life. You just don't know how things will play out. When you're old, you very well may have 9-year stretches of winters approaching those of 20th century Tallahassee or Savannah. As JB would say, "enjoy the weather, it's the only weather you got."

[TheClimateChanger]

6 minutes ago, TheClimateChanger said:

True. The 9-year mean of 39.3F at BWI compares favorably to GSO's mean of 39.3F from 1933-34 to 1987-88, and the 9-year mean of 42.0F at DCA compares favorably to CLT's 1943-44 to 1987-88 mean of 42.3F and is nearly 1F warmer than RDU's 1944-45 to 1987-88 mean of 41.2F.

But it's best not to take anything for granted. These very well could be the best winters of the rest of your life. You just don't know how things will play out. When you're old, you very well may have 9-year stretches of winters approaching those of 20th century Tallahassee or Savannah. As JB would say, "enjoy the weather, it's the only weather you got."

I mean look at it this way. If you told a typical Washingtonian in the early 20th century that in the not too distant future, places high up in the mountains where feet and feet of snow fall each winter would have milder winters than subtropical Washington, they wouldn't be able to fathom it and would call you a crazy person. But that's exactly the case.

Elkins [~2000 feet elev.] has averaged 35.5F since 2015-16, whereas DC averaged 34.9F from 1871-72 to 1917-1918.

It just goes to show you how fleeting life is, and to live by the moment or you'll get left behind in a world that no longer exists.

[psuhoffman]

And Ya'll thought I was depressing 

[CAPE]

2 hours ago, WxUSAF said:

^the mole poleward WPO/EPO ridge is what Webb has been talking about on Twitter. He thinks the current Pac SST pattern favors that. 

CFS has been persistent with that feature for awhile, along with the stretched TPV idea. Between the 2 there should be a mechanism to deliver some legit cold at times. Gets going in Dec on latest runs then adds in a little -NAO action for Jan and Feb. For now, we can dream.

[CAPE]

We can get colder air in a Nina than a Nino. Those big storms in Jan of 17 and 18 were cold powder right on the coast. Jan 22 was a cold month with 3 snowstorms for a good chunk of our region. Beaches did best overall- 17, 18, and 22 all featured 12"+snowtorms for the immediate coast of the MA, with 2 being blizzards. Bit of a short term Nina trend there.

[dailylurker]

10 minutes ago, CAPE said:

We can get colder air in a Nina than a Nino. Those big storms in Jan of 17 and 18 were cold powder right on the coast. Jan 22 was a cold month with 3 snowstorms for a good chunk of our region. Beaches did best overall- 17, 18, and 22 all featured 12"+snowtorms for the immediate coast of the MA, with 2 being blizzards. Bit of a short term Nina trend there.

I feel like 95 to the coast has better winters in a La Nina realm. My gut says 95 to Cambridge is the jack zone this season. 

[CAPE]

1 minute ago, dailylurker said:

I feel like 95 to the coast has better winters in a La Nina realm. My gut says 95 to Cambridge is the jack zone this season. 

Relative to averages I agree. PSU land will still get more snow than the beaches, despite being largely missed by those storms. Maybe 2022 was close. There were places in lower DE that were right around 25" for that winter.