Mid/Late February will be rocking. (This year we mean it!) February long range discussion.

[CAPE]

1 minute ago, Stormchaserchuck1 said:

I like the EPO negative, and +PNA we haven't really seen this Winter.  I was just pointing out that LR models have been really bad, they keep showing an El Nino pattern, but since the El Nino developed in April, we never had a +pna. In Oct-Nov, I was saying the mean pattern in the SW N. Pacific was a ridge for a Strong Nino! It's no surprise the Euro weeklies busted and we only have some weak +pna in the medium range here. I'm worried that next Winter the pendulum may swing completely toward what you are calling -PDO. 

I get what you are saying about patterns that used to work.. and I agree, the PNA has a precipitation correlation here that is actually greater than the temperature correlation in the Wintertime! That means the net air temps+precip makes -PNA more favorable for snow than +PNA. The deceiving thing is coastal lows forms much stronger in +PNA, there is a +0.3 correlation vs -0.3 for -PNA.. so if you look at SLP you would say +PNA Is the obvious better pattern. 

I think it's somewhat +AMO related. We've been getting this ridge where the Hadley Cell meets the mid-latitude Cell.. it started on the West coast, and especially the SW where it stopped raining after 1995. The Pacific used to go into SF a lot, now it doesn't even rain there anymore.. the jet goes all the way up into Alaska.. Over the last few years, that pattern in the mid-latitudes has made it to the east coast. 

The tropical forcing can't make it east of the MC for more than a minute. Not very Nino-like. When it persists in the crappy phases, we get more jet retraction, and -PNA. 

[Wetbulbs88]

1 hour ago, JenkinsJinkies said:

So is it safe to say that this year being AN for the metros is off the table?

If you need a sense of certainty, I guess. If you’re being realistic, it’s impossible to say. 

[stormy]

18 hours ago, clskinsfan said:

We arent even in the middle of the current interglacial yet. The planet will get way warmer before it happens. Although maybe we have sped it up.

I will be brief with an answer before deferring to the C.C. Thread.

You obviously misunderstand the premise.

This study suggests that the Glacial-interglacial cycles are not germane anymore because of our CO2 transgressions.

The climate gurus at the U.N. said 5 years ago that it would be more than 300 years before the AMOC shuts down.  Now, many scientists are saying with the AMOC at its weakest in 1,600 years, it could shut down completely between 2025 and 2095.

[Steve25]

If there's one thing I've learned from the process in here over the past few weeks, no matter what anyone is saying, if Bob Chill isn't in here expressing legitimate excitement/interest, we should probably temper expectations.  

Unless I missed any positivity from him, he's been awfully quiet during this period when many were going wild hyping up the 15th-25th. 

[Jebman]

Just now, stormy said:

I will be brief with an answer before deferring to the C.C. Thread.

You obviously misunderstand the premise.

This study suggests that the Glacial-interglacial cycles are not germane anymore because of our CO2 transgressions.

The climate gurus at the U.N. said 5 years ago that it would be more than 300 years before the AMOC shuts down.  Now, many scientists are saying with the AMOC at its weakest in 1,600 years, it could shut down completely between 2025 and 2095.

That's serious stuff. But we would all get snow

[Ralph Wiggum]

49 minutes ago, Stormchaserchuck1 said:

I get what you are saying about patterns that used to work.. and I agree, the PNA has a precipitation correlation here that is actually greater than the temperature correlation in the Wintertime! That means, the net air temps+precip makes -PNA more favorable for snow than +PNA. 

This could theoretically work, -PNA, EPO ridge (cold air source), big NAO block keeping lows from cutting (track under the region). 

[Stormchaserchuck1]

6 minutes ago, Ralph Wiggum said:

This could theoretically work, -PNA, EPO ridge (cold air source), big NAO block keeping lows from cutting (track under the region). 

I know if we get a Stratosphere warming soon, like a lot of models are saying, we could get a bigger -NAO down the line. 

That was really my basis for thinking this could be a better Winter. This will be the 3rd Stratosphere warming.. another strong ENSO/strong QBO hit on 10mb conditions. 

[BTRWx's Thanks Giving]

28 minutes ago, Ralph Wiggum said:

This could theoretically work, -PNA, EPO ridge (cold air source), big NAO block keeping lows from cutting (track under the region). 

Do you really expect a cfs model for 3 weeks away to verify?

[Stormchaserchuck1]

Major trough in the NW on LR 12z GEFS.. that's been the Spring pattern lately. 

https://ibb.co/ZBq1Dqm

[psuhoffman]

1 hour ago, Stormchaserchuck1 said:

I like the EPO negative, and +PNA we haven't really seen this Winter.  I was just pointing out that LR models have been really bad, they keep showing an El Nino pattern, but since the El Nino developed in April, we never had a +pna. In Oct-Nov, I was saying the mean pattern in the SW N. Pacific was a ridge for a Strong Nino! It's no surprise the Euro weeklies busted and we only have some weak +pna in the medium range here. I'm worried that next Winter the pendulum may swing completely toward what you are calling -PDO. 

I get what you are saying about patterns that used to work.. and I agree, the PNA has a precipitation correlation here that is actually greater than the temperature correlation in the Wintertime! That means, the net air temps+precip makes -PNA more favorable for snow than +PNA. The deceiving thing is coastal lows form much stronger in +PNA, there is a +0.3 correlation vs -0.3 for -PNA.. so if you look at SLP you would say +PNA Is the obvious better pattern for snow. 

I think it's somewhat +AMO related. We've been getting this ridge where the Hadley Cell meets the mid-latitude Cell.. it started on the West coast, and especially the SW where it stopped raining after 1995. The Pacific Jet used to go into SF a lot, now it doesn't even rain there anymore.. the jet goes all the way up into Alaska.. Over the last few years, that pattern in the mid-latitudes has made it to the east coast.  The AMO changed in 1995, so I would say maybe wait for that to wane..  also, according to the CPC we aren't getting -NAO's nearly as much these days, and the WPO has been positive a lot.

I agree with a lot of this. But why did you expect a +pna in a -PDO Nino?  There have been 4 Moderate/strong -PDO Ninos. None featured a +pna. Mean for the 4 is below. 

3 of the 4 were some of the snowiest winters in history here including 2010!  The one exception was 1973 which was a +QBO and has a crazy +++AO

So if we agree that was an outlier and toss all 3 examples of a -pdo moderate or stronger Nino featured both a -pna and a shit ton of snow.  
 

Actually if you simply take all moderate to strong ninos the mean is a -pna.  It’s only weak modoki ninos like 2003 and 2015 that feature a +pna.  But Baltimore averages 40” of snow in -QBO ninos despite the fact the pna is typically negative.  
 

I never expected a +pna this winter.  My analogs that produced a mean snow of 42” were  -PNA city.  There is something else going on.  It’s not the pna because the pna was negative in past epic snowy ninos.  

 

[Maestrobjwa]

1 hour ago, Steve25 said:

If there's one thing I've learned from the process in here over the past few weeks, no matter what anyone is saying, if Bob Chill isn't in here expressing legitimate excitement/interest, we should probably temper expectations.  

Unless I missed any positivity from him, he's been awfully quiet during this period when many were going wild hyping up the 15th-25th. 

Yeah I was just thinking about that earlier...a quiet Chill isn't the most encouraging thing, lol But also it's a lot of moving parts with the pattern change right now...so there's nothing to say "Alright here it is!" with any certainty anyway.

[Stormchaserchuck1]

16 minutes ago, psuhoffman said:

I agree with a lot of this. But why did you expect a +pna in a -PDO Nino?  There have been 4 Moderate/strong -PDO Ninos. None featured a +pna. Mean for the 4 is below. 

3 of the 4 were some of the snowiest winters in history here including 2010!  The one exception was 1973 which was a +QBO and has a crazy +++AO

 

You're right.. I underrated the -PDO this year. 5/5 non+PNA Mod/Strong Nino Winter's is a pretty compelling stat!  

If -PNA is wetter and +PNA is drier, imagine how much the difference is if you don't account for ENSO! +PNA's have been associated with El Nino's 80% of the time historically, and visa-versa. With wetter than average conditions in El Nino, what a difference the PNA makes in precip-correlation in non-ENSO times. That's why -PNA's in El Nino's have been historically good with -NAO/AO conditions. The Hadley Cell is just expanded right now.. With storms digging into the West Coast the last two Winters though, I don't know that, that isn't in the process of changing.. 

[psuhoffman]

5 minutes ago, Stormchaserchuck1 said:

You're right.. I underrated the -PDO this year. 5/5 non+PNA Mod/Strong Nino Winter's is a pretty compelling stat!  

If -PNA is wetter and +PNA is drier, imagine how much the difference is if you don't account for ENSO! +PNA's have been associated with El Nino's 80% of the time historically, and visa-versa. With wetter than average conditions in El Nino, what a difference the PNA makes in precip-correlation in non-ENSO times. That's why -PNA's in El Nino's have been historically good with -NAO/AO conditions. The Hadley Cell is just expanded right now.. 

That last part is where this all comes together. Maybe right now that just won’t work because everything’s shifted north by the expanded mid latitude circulation 

[Stormchaserchuck1]

3 minutes ago, psuhoffman said:

That last part is where this all comes together. Maybe right now that just won’t work because everything’s shifted north by the expanded mid latitude circulation 

I edited to say that storms are digging into the West coast with more frequency though.. And general High pressure over the SW hasn't been as constant a force the last few years... so maybe we are starting to change the longer term processes (related to the Hadley-mid latitude Cell)?

[Kevin Reilly]

39 minutes ago, Stormchaserchuck1 said:

Major trough in the NW on LR 12z GEFS.. that's been the Spring pattern lately. 

https://ibb.co/ZBq1Dqm

But we haven't begun the best winter pattern in like almost 10 years? 

[Baer16]

Are we all just going to ignore the trends for Tuesday's storm? 18z NAM gets DC N&W basically back in the game. 

[psuhoffman]

4 minutes ago, Baer16 said:

Are we all just going to ignore the trends for Tuesday's storm? 18z NAM gets DC N&W basically back in the game. 

Oh I’m seeing it. But there is another thread and even if that does trend better I’m likely to do a lot better so I’m sensitive in those scenarios not to say much.  I feel bad for everyone else when I get snow and they don’t. 

[BTRWx's Thanks Giving]

Was eps a dud?

[Weather Will]

Latest from NWS for the upcoming Pres. weekend, 30% is bullish a week out.

Uncertainty lies amongst the models for the upcoming weekend. On
Saturday a cold front will sit near the region with an area of low
pressure developing along the Gulf/southern U.S. The placement of
the front and track of the low has yet to be resolved along with the
placement of high pressure over eastern Canada. Temperatures will be
cooler as a result with highs in the 30s and 40s. Given model
uncertainty in regards to the track and placement of the
aforementioned features a wide array of precipitation types are
possible. We`ll continue to monitor this system as it evolves in the
coming days.

Saturday

A chance of snow. Mostly cloudy, with a high near 42. Chance of precipitation is 30%.

Saturday Night

A chance of snow. Mostly cloudy, with a low around 28. Chance of precipitation is 30%.

[BTRWx's Thanks Giving]

1 hour ago, psuhoffman said:

I agree with a lot of this. But why did you expect a +pna in a -PDO Nino?  There have been 4 Moderate/strong -PDO Ninos. None featured a +pna. Mean for the 4 is below. 

3 of the 4 were some of the snowiest winters in history here including 2010!  The one exception was 1973 which was a +QBO and has a crazy +++AO

So if we agree that was an outlier and toss all 3 examples of a -pdo moderate or stronger Nino featured both a -pna and a shit ton of snow.  
 

Actually if you simply take all moderate to strong ninos the mean is a -pna.  It’s only weak modoki ninos like 2003 and 2015 that feature a +pna.  But Baltimore averages 40” of snow in -QBO ninos despite the fact the pna is typically negative.  
 

I never expected a +pna this winter.  My analogs that produced a mean snow of 42” were  -PNA city.  There is something else going on.  It’s not the pna because the pna was negative in past epic snowy ninos.  

 

That's really interesting.

[GaWx]

1 hour ago, psuhoffman said:

I agree with a lot of this. But why did you expect a +pna in a -PDO Nino?  There have been 4 Moderate/strong -PDO Ninos. None featured a +pna. Mean for the 4 is below. 

3 of the 4 were some of the snowiest winters in history here including 2010!  The one exception was 1973 which was a +QBO and has a crazy +++AO

So if we agree that was an outlier and toss all 3 examples of a -pdo moderate or stronger Nino featured both a -pna and a shit ton of snow.  
 

Actually if you simply take all moderate to strong ninos the mean is a -pna.  It’s only weak modoki ninos like 2003 and 2015 that feature a +pna.  But Baltimore averages 40” of snow in -QBO ninos despite the fact the pna is typically negative.  
 

I never expected a +pna this winter.  My analogs that produced a mean snow of 42” were  -PNA city.  There is something else going on.  It’s not the pna because the pna was negative in past epic snowy ninos.  

 

 @Stormchaserchuck1 has a very good chance at getting his +PNA for 2023-4 (assuming that’s what he predicted). More on that below. Also, according to the NOAA monthly PNA table for DJFM, 1963-4 and 2009-10 both averaged +PNA with 1963-4 at +0.5 and 2009-10 at +1.0. It has 1972-3 at neutral (+0.1). Only 1965-6 of these 4 averaged a -PNA (-0.4):

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.pna.monthly.b5001.current.ascii.table
 
 2023-4 is so far averaging +PNA with both Dec and Jan positive. Feb 1-11 has also averaged +PNA. The forecast through Feb 18 is for more +PNA before dropping to neutral and then moderately negative. (See image below) So, there’s a very good chance that Feb overall will average a modest +PNA with a small chance to end up neutral.

 Thus with only March to go, 2023-4 has a very good chance to end up averaging +PNA in the table though I give it a small chance to end up neutral (that would obviously require a strong -PNA in Mar). I consider neutral to be +0.25 to -0.25:

 

[Kevin Reilly]

Umm I am NOT ignoring the trend on the NAM clearly more south and a bit stronger!

That is from the NAM an undeniable switch to heavy snow just after 6 am in Delaware County. 

[psuhoffman]

22 minutes ago, GaWx said:

 @Stormchaserchuck1 has a very good chance at getting his +PNA for 2023-4 (assuming that’s what he predicted). More on that below. Also, according to the NOAA monthly PNA table for DJFM, 1963-4 and 2009-10 both averaged +PNA with 1963-4 at +0.5 and 2009-10 at +1.0. It has 1972-3 at neutral (+0.1). Only 1965-6 of these 4 averaged a -PNA (-0.4):

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.pna.monthly.b5001.current.ascii.table
 
 2023-4 is so far averaging +PNA with both Dec and Jan positive. Feb 1-11 has also averaged +PNA. The forecast through Feb 18 is for more +PNA before dropping to neutral and then moderately negative. (See image below) So, there’s a very good chance that Feb overall will average a modest +PNA with a small chance to end up neutral.

 Thus with only March to go, 2023-4 has a very good chance to end up averaging +PNA in the table though I give it a small chance to end up neutral (that would obviously require a strong -PNA in Mar). I consider neutral to be +0.25 to -0.25:

 

Numerical indexes don’t often match the realities of the long wave pattern.  That’s why I post the h5 never index values.  Anomalies in one part of a domain can skew the values. Also what we focus on as the “pna” is actually only one small part of the domain (western US) but it’s the part that matters most for our snow. When people day PNA there usually what they’re referring too, a western US trough, even if technically the pna might not be negative due to other parts of the domain. 

[DarkSharkWX]

2 hours ago, psuhoffman said:

I agree with a lot of this. But why did you expect a +pna in a -PDO Nino?  There have been 4 Moderate/strong -PDO Ninos. None featured a +pna. Mean for the 4 is below. 

3 of the 4 were some of the snowiest winters in history here including 2010!  The one exception was 1973 which was a +QBO and has a crazy +++AO

So if we agree that was an outlier and toss all 3 examples of a -pdo moderate or stronger Nino featured both a -pna and a shit ton of snow.  
 

Actually if you simply take all moderate to strong ninos the mean is a -pna.  It’s only weak modoki ninos like 2003 and 2015 that feature a +pna.  But Baltimore averages 40” of snow in -QBO ninos despite the fact the pna is typically negative.  
 

I never expected a +pna this winter.  My analogs that produced a mean snow of 42” were  -PNA city.  There is something else going on.  It’s not the pna because the pna was negative in past epic snowy ninos.  

 

this is very interesting, especially 1964

but to be fair though the block is defintely weaker than previously modeled, and the pac has gotten worse too

i wish there was a way to properly compare the 500h archive maps on psl to what models have right now; do you still think the pattern is good and can produce considering the downtrends we've been seeing?
 

[MDScienceTeacher]

3 hours ago, stormy said:

I will be brief with an answer before deferring to the C.C. Thread.

You obviously misunderstand the premise.

This study suggests that the Glacial-interglacial cycles are not germane anymore because of our CO2 transgressions.

The climate gurus at the U.N. said 5 years ago that it would be more than 300 years before the AMOC shuts down.  Now, many scientists are saying with the AMOC at its weakest in 1,600 years, it could shut down completely between 2025 and 2095.

The cycles depicted above are caused by variation in the earths orbit and the resulting impact on solar radiation.  That’s an external force that is so much greater than manmade C02 emissions. It will be interesting to see if the current warming has any impact on glacial interglacial cycles but to say that they are not germane any more is foolish.  Anything generated by the earth follows the laws of conservation of mass.. this generally limits the level of impact human beings can have on climate.   Solar radiation on the other hand will likely trump anything that comes from the earth itself. 

[Terpeast]

4 hours ago, psuhoffman said:

The Dec “anafront” wave that I got 4”. It wasn’t actually an anafront. It was on long range guidance. It morphed into a nice caboose wave where the mid level and surface track was perfect for DC and Balt. I was actually NW of the best precip with that wave.  Only reason I was the snow max was the places further east that should have been were too warm!
 

 And the 850s were displaced well southeast of the actual rain snow line, east of 95, the whole event. Historically with these trailing waves behind a front the 850 and snow line are not that disconnected!  
 

Imo if I showed you just the h5, h7, h85, mslp, and qpf plots and said “where is the snow max” you’d probably say a nice 3-6 stripe right through DC/Balt. But they got white rain instead.  
 

I know it wasn’t as significant as the Jan 7 wave. That one could have been 6-10” if it was just colder. I know the slp took a slightly inside track but that’s because of the crap thermals. The mid and upper track of that wave was perfect and with better thermals the slp doesn’t jog inside and end up under mid level low like that imo. But those little 3-4” snows being subtracted add up.
 

 I’m not saying all 3 definitely should have been snow. I’m not saying every perfect track system in a bad thermal regime was snow in the past. But a significant % was. So I take note when they all seem to fail. If we go back through the last 7 years which we all know have been the worst snow period in DC/Balt recorded history, if we simply flip about 1/3 of all these perfect wave pass winter rainstorms to snow, it still wouldn’t be some epic good period. But we wouldn’t be talking about it the same way. We would simply be in the midst of one of our more typical down snow cycles that happen regularly through history. What’s made it awful instead of just bad is this phenomenon imo. 

I don’t know what the 3rd one was, but that dec event - I’m not sure I agree that its a good example. It was more of a function of timing with cold air’s arrival during the precip event. It morphed from an anafront to a wave along the front. It would have happened the same way 60 years ago vs today, and had that wave been 6 hours slower, we would have gotten a nice 3-6” event across the metros. 

Jan 7 is the more glaring example, to me. That’s what prompted me to lower my expectations for the rest of the season. Had it been colder, the low would have taken a track 50-100 miles souther than it did, and we’d have gotten 6-12”+

[psuhoffman]

5 minutes ago, Terpeast said:

I don’t know what the 3rd one was, but that dec event - I’m not sure I agree that its a good example. It was more of a function of timing with cold air’s arrival during the precip event. It morphed from an anafront to a wave along the front. It would have happened the same way 60 years ago vs today, and had that wave been 6 hours slower, we would have gotten a nice 3-6” event across the metros. 

Jan 7 is the more glaring example, to me. That’s what prompted me to lower my expectations for the rest of the season. Had it been colder, the low would have taken a track 50-100 miles souther than it did, and we’d have gotten 6-12”+

My conviction on this is not 100%  Im open to having my mind changed on the Dec wave. But what I noted was the cold at the mid levels got in ahead of the wave. But the boundary, even up here, was a mess. Places close to 95 had snow for hours it just couldn’t really accumulate.  I don’t even think it was getting colder in the boundary. It seemed to me what cold there was got in in time it just want cold enough and not sure another 6 hours would have mattered that much. But again I could be wrong here. That one I’m willing to adjust my opinion on. But Jan 7. There was no excuse for that ish. 

[psuhoffman]

@Terpeast the 3rd wave is tomorrow. It’s actually a sneaky ok long wave pattern to get an unexpected snow. I saw a few 4-8” type wet snow events in this type of setup in my case studies. It’s sneaky because none of the features is anomalous and sticks out but there is a subtle 50/50, subtle western ridge, a nice little ridge near Hudson and it’s an stj wave coming across at a low latitude. You. A see the suppressive influence in that the wave can’t gain much lat despite no cold at all in front of it. prime climo I think it’s reasonable to say we could have snuck some snow out of this despite the crap airmass in front of it in the past. Not for sure. Again it’s not any one or these it’s the accumulation that’s troubling. 

[stormy]

20 minutes ago, MDScienceTeacher said:

The cycles depicted above are caused by variation in the earths orbit and the resulting impact on solar radiation.  That’s an external force that is so much greater than manmade C02 emissions. It will be interesting to see if the current warming has any impact on glacial interglacial cycles but to say that they are not germane any more is foolish.  Anything generated by the earth follows the laws of conservation of mass.. this generally limits the level of impact human beings can have on climate.   Solar radiation on the other hand will likely trump anything that comes from the earth itself. 

  Foolishness will have to be taken up with the scientists who conducted this study because they are saying that an abrupt interruption of natural cycles very similar to the Younger Dryas may be coming soon. It could have devastating impact around the world.

When you say that the level of impact that humans can have on the climate is limited, I believe You and I could be friends.

Enjoy the Super Bowl.

[SnowenOutThere]

14 minutes ago, stormy said:

When you say that the level of impact that humans can have on the climate is limited, I believe You and I could be friends

Blud thinks he assembling a team