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powderfreak

Early Winter Banter, Observations & General Discussion 2017

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25 minutes ago, OceanStWx said:

Sort of. It's a hybrid 4DVAR.

We're getting pretty deep into the weeds here, but as I understand it (which could be wrong) the 4DenVAR the NGGPS uses takes some assumptions used in 3DVAR and carries them over. The "en" in 4DenVAR stands for ensemble, which it uses to create trajectories that sample background errors. More simply, the ob is compared to the first guess, then it passes to the ensemble which spits out all the ways the first guess should be adjusted. 

The advantage is that it is flexible and scalable for future upgrades. The disadvantage is that it still relies on climatological covariance more. So we need a bigger and better ensemble. More of the reason why the supercomputer is being upgraded.

I'm intrigued by the idea.  I know the model itself gets a bad name but if the physics/data assimilation behind it are solid it should be ok.  That was always an issue with the GFS.  They could never go to a fully 4dvar system due to the shear amount of data/computing power that would have been need to do so.  Running all the different HiRES and short-term models eats up a lot of computing space.  This is what make the Euro so special/unique.  Only runs twice a day. Boom.

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26 minutes ago, Baroclinic Zone said:

I'm intrigued by the idea.  I know the model itself gets a bad name but if the physics/data assimilation behind it are solid it should be ok.  That was always an issue with the GFS.  They could never go to a fully 4dvar system due to the shear amount of data/computing power that would have been need to do so.  Running all the different HiRES and short-term models eats up a lot of computing space.  This is what make the Euro so special/unique.  Only runs twice a day. Boom.

I mean it's possible at least I'll be able to view (:devilsmiley:) experimental FV3-GFS data (GFS with the new core) by this summer. 

I do think the reason they chose the 4DenVAR is to expand the ensemble system and make it more robust but nimble at the same time. But I really do need the modelers to dumb it down for me. Nothing makes an operational forecaster sweat more than partial differential equations without explanations.

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Just now, OceanStWx said:

I mean it's possible at least I'll be able to view (:devilsmiley:) experimental FV3-GFS data (GFS with the new core) by this summer. 

I do think the reason they chose the 4DenVAR is to expand the ensemble system and make it more robust but nimble at the same time. But I really do need the modelers to dumb it down for me. Nothing makes an operational forecaster sweat more than partial differential equations without explanations.

I leave that **** up to you. :lol:  I'm 20+ years past caring about math.

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7 minutes ago, HoarfrostHubb said:

Coastal damage would still be the same. Wind damage to trees would still be the same.

No cars stranded I agree, maybe better snow clearing?  We needed huge National Guard front end loaders to clear our street a week after the storm. Not sure how that could be improved.  My school would still collapse (my elementary school roof caved in).

Fewer deaths, maybe a quicker return to normalcy for most.  Def a more aware public, more homes with generators, etc.

Yes...agree.

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15 minutes ago, HoarfrostHubb said:

Coastal damage would still be the same. Wind damage to trees would still be the same.

No cars stranded I agree, maybe better snow clearing?  We needed huge National Guard front end loaders to clear our street a week after the storm. Not sure how that could be improved.  My school would still collapse (my elementary school roof caved in).

Fewer deaths, maybe a quicker return to normalcy for most.  Def a more aware public, more homes with generators, etc.

Part of the problem with 1978 was that there were a couple of larger QPF bombs that rolled up the EC ...classic La Nino, marginal thickness high PWAT storms, between the 12th and 22nd of January... 

Cold rain/sleet ended up with huge snow totals.  Logan set a 24-hour snow fall record with (ah, check this) but I wanna say 19" on the 21st? 

Anyway, the CSB storm  on the 25-28th did some serious pack erosion, but those ginormous snow banks contained huge water content frozen solid into immovable berms everywhere; and were not eroded back enough to make way for the Feb blizzard with its 26-31F high moisture content two feet ... three is some areas.

There's a difference between these ... cobweb whiteouts we've been getting from these -EPO storms... versus the bluer tinted blitzkriegs that dump the same number of inches. That's why I'll always be impressed by February 2015, but just impressed.

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1 minute ago, Typhoon Tip said:

Part of the problem with 1978 was that there were a couple of larger QPF bombs that rolled up the EC ...classic La Nina marginal PWAT storms, between the 12th and 22nd of January... 

Cold rain/sleet ended up with huge snow totals.  Logan set a 24-hour snow fall record with (ah, check this) but I wanna say 19" on the 21st? 

Anyway, the CSB storm  on the 25-28th did some serious pack erosion, but those ginormous snow banks contained huge water content frozen solid into immovable berms everywhere; and were not eroded back enough to make way for the Feb blizzard with its 26-31F high moisture content two feet ... three is some areas.

There's a difference between these ... cobweb whiteouts we've been getting from these -EPO storms... versus the bluer tinted blitzkriegs that dump the same number of inches. That's why I'll always be impressed by February 2015, but just impressed.

Yeah. The earlier Jan storm was a big deal. Set the then record at BOS. And you are right that the Super bomb resulted in a pack decimation. I recall (only in 4th grade) sliding on my school playground on a sheet of glacier leftovers the morning of the Feb 6 storm, wondering why we had to leave school early. I don’t recall berms from the first storm being around but they might have been there. 

Where I lived there are pretty good accounts of over 40” amounts, and the wind created drifts that were humongous. Our VW microbus in our driveway was completely buried (well over the roof), and it wasn’t in a really big drift.    

Feb 2015 (as well as Feb 2013 in CT) seems the closest I have seen.

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3 minutes ago, 40/70 Benchmark said:

Rosenthal was all over,  too.

I miss him..."snowing to beat the band"..

He was a good met. He was actually on channel 3 in Worcester for several years back when they had a news station. Obviously most of you remember him from channel 5 Boston. He had a pretty good forecast for December 1992. Was far more bullish than other mets. I felt like his local knowledge of ORH hills helped him on that one. 

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2 minutes ago, ORH_wxman said:

He was a good met. He was actually on channel 3 in Worcester for several years back when they had a news station. Obviously most of you remember him from channel 5 Boston. He had a pretty good forecast for December 1992. Was far more bullish than other mets. I felt like his local knowledge of ORH hills helped him on that one. 

Is he from ORH?

He doesn't age lol

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1 minute ago, ORH_wxman said:

He was a good met. He was actually on channel 3 in Worcester for several years back when they had a news station. Obviously most of you remember him from channel 5 Boston. He had a pretty good forecast for December 1992. Was far more bullish than other mets. I felt like his local knowledge of ORH hills helped him on that one. 

He still does forecasts for some radio outlets.  I've heard him on WBIX-AM Boston, 1260.

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78 was reasonable well forecasted but the onset was a few hours late so a lot of folks thought it a bust and proceeded with their business.  Also, the event 2 weeks earlier was a bust (a good one as rain was forecasted and nearly 2 feet of snow fell) and folks were skeptical of the forecasts but in general.

 

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3 minutes ago, 40/70 Benchmark said:

Is he from ORH?

He doesn't age lol

I actually don't know if he is from ORH as in grew up there but he def lived in the area for a while. 

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Just now, weathafella said:

Rosenthal also in addition to being a good met is a nice man.  The media business is rough.

Yes. Kudos to our boy Ryan for surviving the rat race. The weather channel dumped Bill keneely years ago in favor of a series bimbos. He was one of their best and I can drive pretty much anywhere in America without a map thanks to Bill keneely.

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78 was so bad locally because of the timing and instant flurries to dumping. Winds were cranking from the get go too. I was going to URI, started flurries. I knew what was coming taking Met classes, saw the Difax Sat pic. I immediately headed for home in Westerly 20 minutes away by the time I got home nearly 4 inches was on the ground. I have seen all the big ones, intensity wise 78 is shoulders above 93 13 and 11. 

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6 minutes ago, weathafella said:

78 was reasonable well forecasted but the onset was a few hours late so a lot of folks thought it a bust and proceeded with their business.  Also, the event 2 weeks earlier was a bust (a good one as rain was forecasted and nearly 2 feet of snow fell) and folks were skeptical of the forecasts but in general.

 

Very very true

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