Model Mehham

[dendrite]

May can correlate if the blocking is extreme enough.

[forkyfork]

those maps shouldn't even exist

[powderfreak]

59 minutes ago, Damage In Tolland said:

Everyone would. It's warm season. Anyone who wants cold, clouds, wearing jackets , heating units on all day this time of year needs serious help. 

Say no to heating but can't wait to run the AC 24/7 in late April and early May.  You are an interesting cat.

That doesn't mean I want it to be 42F like you will reply, but let's just do some 75/45 for a while.  That'd be nice.

[CoastalWx]

7 minutes ago, powderfreak said:

Say no to heating but can't wait to run the AC 24/7 in late April and early May.  You are an interesting cat.

That doesn't mean I want it to be 42F like you will reply, but let's just do some 75/45 for a while.  That'd be nice.

Seasons in seasons. Let them be.

[NJwx85]

-4 to -8 C 850mb temps to NYC on Monday on the 12z ECMWF.

[Ginx snewx]

2 hours ago, CoastalWx said:

 

 Using a total month as a correlation without breaking block intensity down in that correlation is the issue. Also correlation can be higher earlier in the month of May. As shown many times using correlation over an entire month leads to inaccurate  smoothed out numbers. If the response earlier included only NAO numbers over say 200 in the first two weeks of May then we would have useful numbers to look at

 

[CoastalWx]

Just now, Ginx snewx said:

 Using a total month as a correlation without breaking block intensity down in that correlation is the issue. Also correlation can be higher earlier in the month of May. As shown many times using correlation over an entire month leads to inaccurate  amoothed out numbers. If the response earlier included only NAO numbers over say 200 in the first two weeks of May then we would have useful numbers to look at

 

LOL, thanks for the tip. It still doesn't change the data. Anomalous blocks cause anomalous weather. I don't think time of month has a big difference. You aren't going to see the early part and late parts of the month deviate cause a net cancellation in the correlation means. We also said many times that if you have a well placed strong block, it will make a difference. 

[ORH_wxman]

22 minutes ago, Ginx snewx said:

 Using a total month as a correlation without breaking block intensity down in that correlation is the issue. Also correlation can be higher earlier in the month of May. As shown many times using correlation over an entire month leads to inaccurate  smoothed out numbers. If the response earlier included only NAO numbers over say 200 in the first two weeks of May then we would have useful numbers to look at

 

The correlation is already declining pretty fast in April (down to about 0.2)...so it's not going to be very influential in early May.

 

 

[Bostonseminole]

yeah, this weather sucks, but I also don't want the high humidity crap.. but 75/50 would be nice.. at least the grass is happy.

[Whineminster]

44 minutes ago, ORH_wxman said:

The correlation is already declining pretty fast in April (down to about 0.2)...so it's not going to be very influential in early May.

Don't you poo poo the king of kold. 

[Ginx snewx]

54 minutes ago, Whineminster said:

Don't you poo poo the king of kold. 

Odd reply thanks for adding scientific discussion 

[Ginx snewx]

1 hour ago, Bostonseminole said:

yeah, this weather sucks, but I also don't want the high humidity crap.. but 75/50 would be nice.. at least the grass is happy.

This weather was pretty nice this afternoon and it was 75/50 at 5 here

[Ginx snewx]

2 hours ago, CoastalWx said:

LOL, thanks for the tip. It still doesn't change the data. Anomalous blocks cause anomalous weather. I don't think time of month has a big difference. You aren't going to see the early part and late parts of the month deviate cause a net cancellation in the correlation means. We also said many times that if you have a well placed strong block, it will make a difference. 

So you are saying a strong west NAO correlates to temps in May as was originally posted then refuted, let's remember the original post and subsequent rebuttals.

 

[Typhoon Tip]

4 hours ago, dendrite said:

May can correlate if the blocking is extreme enough.

Yeah agreed - Will and i discussed this last week about "thresholds" too. 

We surmised that say ...-1 or even -2 SD events may get absorbed into the noise of the atmosphere because of the discontinuity in wave numbers that takes place as the winter patterns break toward summer...etc.  However, given a sufficiently powerful block ...say -4 and particularly details in its position (west vs east) and we'd see forcing/modulation of the anomaly distribution.  

Trick is... how often is even a -3 SD anomaly in the NAO domains space?  The bell-curve mass of them all are probably between -.5 and -2.5... So you'd have to actually do a more advanced vetting process than just saying -NAO or +NAO...and condition it around real-time scenarios to find the "hidden" correlations - the ones that really matter. 

[Typhoon Tip]

NAO aside... 

Since the "nadir runs" of yesterday, the 00z and now 12z Euro cluster has incrementally lessened the severity ...if not in the hard numbers, the "complexion" of the handling between Ds 4 and 10.  

In fact, more observably the trough's structure is slightly more opened up and spends a couple of days actually with its axis slightly east of our latitude.  It's also perhaps 3 to 6 decameters shallower in the deepest intervals.  

I mean these are not a huge improvements for spring enthusiasts but they do cut down on the direct schit implications a little.   About six more cycles in this trend (haha) we might limit this assault to tolerable negatives...  

Unfortunately, though the GEFs tele's (as others have noted) are pretty stridently adamant about hiatus of spring until perhaps the 15th or 20th so...  

[Bostonseminole]

This weather was pretty nice this afternoon and it was 75/50 at 5 here

Yeah in the PM was good, but noticed the mosquitoes came right out.


Sent from my iPhone using Tapatalk

[#NoPoles]

3 hours ago, Typhoon Tip said:

NAO aside... 

Since the "nadir runs" of yesterday, the 00z and now 12z Euro cluster has incrementally lessened the severity ...if not in the hard numbers, the "complexion" of the handling between Ds 4 and 10.  

In fact, more observably the trough's structure is slightly more opened up and spends a couple of days actually with its axis slightly east of our latitude.  It's also perhaps 3 to 6 decameters shallower in the deepest intervals.  

I mean these are not a huge improvements for spring enthusiasts but they do cut down on the direct schit implications a little.   About six more cycles in this trend (haha) we might limit this assault to tolerable negatives...  

Unfortunately, though the GEFs tele's (as others have noted) are pretty stridently adamant about hiatus of spring until perhaps the 15th or 20th so...  

I wish there was a "sad face" button

[CoastalWx]

6 hours ago, Ginx snewx said:

So you are saying a strong west NAO correlates to temps in May as was originally posted then refuted, let's remember the original post and subsequent rebuttals.

 

Not sure what you mean. A near record block can and will effect weather even if typical correlations aren't as robust. Fwiw, there was more of a correlation to wet weather which I than mentioned perhaps affecting high temps more so than cold temps. But that was more anecdotal. 

[ORH_wxman]

Euro is pretty interesting at day 8. 

[Typhoon Tip]

I keep wondering this ...

If we could take the present day modeling technology et al, and transport it back to a week before the 1977 snow event ...  would we be seeing something similar? 

I think it would be a neat project to parameterize the models for each specific event in history and sort of iteratively run them until you produced the exact repro of the event in question.   THEN, start fiddling with the inputs to force different outcomes - ho ho man ... that would be obsessively consuming .. probably keel over from dehydration and malnourishment like those Korean gamers ... I could whip us up an 1888er in July if I got my hands on those crays - just need a solid volcano and some imagination and we can cancel a summer proper -

If it's gonna snow ...snow... otherwise, don't dink around with the worst - getting us close and just having misery to show for it.  Which is unfortunately still the more likely outcome. 

I did see the D8 Euro though and it's ... bringing back to that question: if we could see the present day modeled output for a week before that '77 event I wonder if it would show up like what we are seeing.  Uber -NAO dip and a continental conduit of cold entangled into an instability trough ftw -

[ORH_wxman]

34 minutes ago, Typhoon Tip said:

I keep wondering this ...

If we could take the present day modeling technology et al, and transport it back to a week before the 1977 snow event ...  would we be seeing something similar? 

I think it would be a neat project to parameterize the models for each specific event in history and sort of iteratively run them until you produced the exact repro of the event in question.   THEN, start fiddling with the inputs to force different outcomes - ho ho man ... that would be obsessively consuming .. probably keel over from dehydration and malnourishment like those Korean gamers ... I could whip us up an 1888er in July if I got my hands on those crays - just need a solid volcano and some imagination and we can cancel a summer proper -

If it's gonna snow ...snow... otherwise, don't dink around with the worst - getting us close and just having misery to show for it.  Which is unfortunately still the more likely outcome. 

I did see the D8 Euro though and it's ... bringing back to that question: if we could see the present day modeled output for a week before that '77 event I wonder if it would show up like what we are seeing.  Uber -NAO dip and a continental conduit of cold entangled into an instability trough ftw -

Yeah I have to imagine given the large scale closed center, the May '77 event would be forecast fairly well today inside of 3 or 4 days...though the snow amounts themselves would prob be under-forecast given that most of the snow in that event did fall in about 5-6 hours. An interesting fact in that one is that ORH at 1000 feet never got to freezing...their lowest temp was 33F and they still accumulated 12.7 inches.

 

[ORH_wxman]

On the other hand, the 06z GFS shows you how to get swirling turds regenerating south of New England every time you think you might be escaping the death pattern of 47 and rain...it starts to clear and you get a 62F self-destructing sunshine day with graupel on the high mountain peaks and then another lobe rotates south and reforms the whole surface reflection to the south to put the low level flow back easterly again....almost like the May 2005 nightmare.

[Typhoon Tip]

6 minutes ago, ORH_wxman said:

Yeah I have to imagine given the large scale closed center, the May '77 event would be forecast fairly well today inside of 3 or 4 days...though the snow amounts themselves would prob be under-forecast given that most of the snow in that event did fall in about 5-6 hours. An interesting fact in that one is that ORH at 1000 feet never got to freezing...their lowest temp was 33F and they still accumulated 12.7 inches.

 

 

But I mean seriously ...tell me that doesn't look similar - 

It's certainly not a huge leap from what we're seeing out there.  That D9 for example ...wait, what's the analogs say?  I bet that example is on the list here

 

[dendrite]

5 minutes ago, ORH_wxman said:

Yeah I have to imagine given the large scale closed center, the May '77 event would be forecast fairly well today inside of 3 or 4 days...though the snow amounts themselves would prob be under-forecast given that most of the snow in that event did fall in about 5-6 hours. An interesting fact in that one is that ORH at 1000 feet never got to freezing...their lowest temp was 33F and they still accumulated 12.7 inches.

 

The obs had 32F all during the day until late afternoon...probably warmed to one of those 32.6F deals.

https://www.wunderground.com/history/airport/KORH/1977/5/9/DailyHistory.html?req_city=Worcester&req_state=MA&req_statename=&reqdb.zip=01602&reqdb.magic=12&reqdb.wmo=99999

[ORH_wxman]

1 minute ago, Typhoon Tip said:

But I mean seriously ...tell me that doesn't look similar - 

It's certainly not a huge leap from what we're seeing out there.  That D9 for example ...wait, what's the analogs say?  I bet that example is on the list here

Yeah the closed low placement is certainly pretty close and the thicknesses are there...I'd prob want to see the thermal gradient a little more tightly packed to tighten the low level processes up if we're trying to engineer a '77 repeat....but obviously that type of detail is something that can change a lot in this time range.

[ORH_wxman]

2 minutes ago, dendrite said:

The obs had 32F all during the day until late afternoon...probably warmed to one of those 32.6F deals.

https://www.wunderground.com/history/airport/KORH/1977/5/9/DailyHistory.html?req_city=Worcester&req_state=MA&req_statename=&reqdb.zip=01602&reqdb.magic=12&reqdb.wmo=99999

You're right, not sure why I always thought it was 33....esp since it's really hard to stay 33F when you have heavy snow. It's going to want to latently cool to 32.

[Typhoon Tip]

May 2005 was never 62 for any reason or sensibility of relief for a solid two weeks, though.  

I get what you mean, however, in concept ...where 'refitting' and pulling the close low back retrograde in a cyclic horror story, sure - that specific behavior noted. (just talking about 06z GFS comparison to 2005... etc)

But May 2005 was a uniquely satan rectal plague scenario. I think that was so unique, dark humor aside... that the return rate on that is probably rarer?  That's my opinion, granted, by fair description for that 2005 ordeal really was a minimum of about 12 days spend in the mid 40s with lows around 39, and when it was not misting heavily with a harsh biting wind, it was gales with thrashing Nor'easter rains.  There were not 6 hour reach-around mercies of 60 during that stretch ...and probably not for that third week either.  

[ORH_wxman]

One weird tidbit about both the May '77 storm and the late April '87 storm is that a lot of the snow accumulated in the afternoon...I mean, talk about overcoming some serious insolation.

[CoastalWx]

I saw some great pics of snow on the patio furniture at my grandparents house in Hyde park. That was definitely several inches. 

[Typhoon Tip]

For me it comes down to the air mass a region is working with, as the lion's share of forcing physical outcomes?

The sun is certainly important. Duh. However, a cold thickness drizzly rain with the sun dimly visible in late April is probably light flurries snow in the same air mass in January (for example).  

But, given sufficiently dense overcast and UVM on-going, that fact that it is proven possible to snow in May ( a mere month before the hottest, highest sun angle of the year...) means that the same conditions (relative to solar calendar) "could' happen at the end of July. The sun intensity per se is no different to an exceptionally close approximation, whether 30 days before or aft the Solstice.  

The difference is sourcing ... By the time May flips to page into June, we are integrating the higher latitudes (they are catching up) to the warming on a hemispheric scope - and such that any cold source by then has just been warmed too much for exotic returns.  

As perhaps a 'fuzzy logic' way to think of it, it snowed in the year without a summer because of dimming insolation on the planetary scale from volcanism; that's another way of saying the source regions of cold were not able to warm so it snowed at weird times of the year.  Yet another way ... we are far enough N in latitude that the circumstantial fragility of summer is exposed from rare time to rare time.