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The "It's never too early" 2014-15 Winter Prediction Thread

Vol Man

By Vol Man,
in Tennessee Valley

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LithiaWx

LithiaWx

Posted
Posted

Looks like November :

 

 

 

GSM v12.0.0 - released August 4th, 2014 - scheduled implementation November 2014
 


  • Upgrade from current operational T574 Eulerian (~23km) to T1534 Semi-Lagrangian (~13km)
  • Use high resolution daily RGT SST instead of weekly OI SST, and use daily sea ice analysis
  • Extend high resolution forecast from 8 days to 10 days
  • Use McICA radiation approximation
  • Reduced drag coefficient at high wind speeds
  • Hybrid EDMF PBL scheme and TKE dissipative heating
  • Retuned ice and water cloud conversion rates, background diffusion of momentum and heat
  • Retuned orographic gravity-wave forcing and mountain block, etc.
  • Change from Lagrangian to Hermite interpolation in the vertical to reduce stratospheric temperature cold bias
  • Restructured physics and dynamics restart fields and updated sigio library
  • Consistent diagnosis of snow accumulation in post and model
  • Compute and output frozen precipitation fraction
  • Divergence damping in the stratosphere to reduce noise
  • Added a tracer fixer for maintaining global column ozone mass
  • Stationary convective gravity wave drag
  • New blended snow analysis to reduce reliance on AFWA snow
  • Changes to treatment of lake ice to remove unfrozen lake in winter
  • Modified initialization to reduce a sharp decrease in cloud water in the first model time step
  • Correct a bug in the condensation calculation after the digital filter is applied
  • Accumulation bucket changed from 12 hour to 6 hour between day 8 and day 10
  • Land Surface changes
    • Replace Bucket soil moisture climatology by CFS/GLDAS
    • Add the vegetation dependence to the ratio of the thermal and momentum roughness
    • Fixed a momentum roughness issue

Read the full release notes here for GSM v12.0.0

Also see GSI and EnKF release notes for upcoming implemention:
GSI v5.0.0
EnKF v2.0.1

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  • 2 weeks later...
tnweathernut

tnweathernut

Posted
Posted

The AO is really taking a dive currently.  I hope we will realize a -AO October.  It usually means a -AO Dec-February.  Just one piece of the puzzle, but I'd much rather have it on my side than not.

Anyone else wondering if we stay neutral positive in the Pacific or reach a weak positive El Nino?  I have seen where weak positives usually mean precipitation will be below normal in the southeast for the winter.

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John1122

John1122

Posted
Posted

The last time it was this negative in October was 2009 I believe, It's currently about as negative as it ever gets this time of year, last year it was also mostly negative in October, but not as negative as it is currently. The NAO was also negative throughout October 2009 and is currently negative and expected to stay negative for the next 14 days.

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Stovepipe

Stovepipe

Posted
Posted

Looks like November :

 

 

 

GSM v12.0.0 - released August 4th, 2014 - scheduled implementation November 2014

 

  • Upgrade from current operational T574 Eulerian (~23km) to T1534 Semi-Lagrangian (~13km)
  • Use high resolution daily RGT SST instead of weekly OI SST, and use daily sea ice analysis
  • Extend high resolution forecast from 8 days to 10 days
  • Use McICA radiation approximation
  • Reduced drag coefficient at high wind speeds
  • Hybrid EDMF PBL scheme and TKE dissipative heating
  • Retuned ice and water cloud conversion rates, background diffusion of momentum and heat
  • Retuned orographic gravity-wave forcing and mountain block, etc.
  • Change from Lagrangian to Hermite interpolation in the vertical to reduce stratospheric temperature cold bias
  • Restructured physics and dynamics restart fields and updated sigio library
  • Consistent diagnosis of snow accumulation in post and model
  • Compute and output frozen precipitation fraction
  • Divergence damping in the stratosphere to reduce noise
  • Added a tracer fixer for maintaining global column ozone mass
  • Stationary convective gravity wave drag
  • New blended snow analysis to reduce reliance on AFWA snow
  • Changes to treatment of lake ice to remove unfrozen lake in winter
  • Modified initialization to reduce a sharp decrease in cloud water in the first model time step
  • Correct a bug in the condensation calculation after the digital filter is applied
  • Accumulation bucket changed from 12 hour to 6 hour between day 8 and day 10
  • Land Surface changes
    • Replace Bucket soil moisture climatology by CFS/GLDAS
    • Add the vegetation dependence to the ratio of the thermal and momentum roughness
    • Fixed a momentum roughness issue

Read the full release notes here for GSM v12.0.0

Also see GSI and EnKF release notes for upcoming implemention:

GSI v5.0.0

EnKF v2.0.1

 

LHgi5cz.jpg

 

Sorry, couldn't resist

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tnweathernut

tnweathernut

Posted
Posted

Eurasian snow over is off to the races this year (-AO anyone?), the PDO is at a level which has traditionally guaranteed a winter +PDO (17 of 17 according to Larry), and a weak El Niño trying to take shape. There are other positives as we begin our descent into winter as well, and very few negatives at this point. All in all, one of the more promising Octobers I can remember, and I have been following and studying winters since the 80's. It will be interesting to see how this year plays out. At the very least, I am encouraged....... Let's get this party started.

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jaxjagman

jaxjagman

Posted
Posted

 

 

 

Eurasian snow over is off to the races this year (-AO anyone?), the PDO is at a level which has traditionally guaranteed a winter +PDO (17 of 17 according to Larry), and a weak El Niño trying to take shape. There are other positives as we begin our descent into winter as well, and very few negatives at this point. All in all, one of the more promising Octobers I can remember, and I have been following and studying winters since the 80's. It will be interesting to see how this year plays out. At the very least, I am encouraged....... Let's get this party started.

 

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Carvers Gap

Carvers Gap

Posted
Posted

 

My trees were slammed this year.  In places I have more acorns than grass.  Cold winter or not, I do predict some fat squirrels.  Maybe that is not a prediction, just an actuality.  Interestingly, it was 5-7 years ago when my oaks did this.  Seems like it was a warm winter, because I made a mental note to ignore it next time.  But nature does know...Unfortunately, I don't know what nature knows. 

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1234snow

1234snow

Posted
Posted

My trees were slammed this year. In places I have more acorns than grass. Cold winter or not, I do predict some fat squirrels. Maybe that is not a prediction, just an actuality. Interestingly, it was 5-7 years ago when my oaks did this. Seems like it was a warm winter, because I made a mental note to ignore it next time. But nature does know...Unfortunately, I don't know what nature knows.

Same here with the acorns. They were plentiful and huge this year. Most and the biggest I've ever seen.

Anyways here is Roberts winter outlook:

post-6441-141472704933.jpg

Seems to jive with every other forecast I've seen for this winter.

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Mr Bob

Mr Bob

Posted
Posted

Looks like Raleigh and Robert combined! I would be fine with the snow and not quite as cold...Jan 2011 as opposed to Jan 2014...The super cold makes me end up working too many hours.

 

As for my opinion....02-03 and 09-10 were epic for other parts of the south but I don't recall much action on this side of the Apps...the earlier had one minor event and late Jan 2010 had a marginal event turn into a traffic disaster in Chatt...a wet sloppy mess that was gone in 24 hours or so. At any rate, I am still not sold on solid cold...I am less gung ho on slightly above but this seems to happen every year when I read the board at this time.

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Mr Bob

Mr Bob

Posted
Posted

2009-10 was my best winter ever for snow. I had almost 50 inches. Snowiest winter here since 1960. There was snow on the ground here for the entire month of February.

And of course I was limited to my Chattanooga experience with that. Did nto think about the rest of E TN....

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John1122

John1122

Posted
Posted

For whatever reason I was thinking Chattanooga also cashed in that winter. Though now that I think of it, Knoxville did far less with the set up that year than the north of 40 areas. I believe there were several marginal events that we're very location driven. Seems like the January 29th-30th event ended up being a messy mix South of the Kentucky border counties. Even Crossville had a lot of freezing rain that lowered their snow totals. I received 13 inches from it. I seem to recall that Chattanooga managed a quick 6 inches or so from that before the warm nose, but maybe I and thinking of a different storm.

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valkhorn

valkhorn

Posted
Posted

 

The trees say nothing about the coming winter because acorn production is done for two years or more prior to a bumper crop in acorns.

 

If anything it's an indication of past weather, not future weather.

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Coach B

Coach B

Posted
Posted

2009-10 was my best winter ever for snow. I had almost 50 inches. Snowiest winter here since 1960. There was snow on the ground here for the entire month of February.

Wow! At the time I considered 2010 to be one of the biggest wastes of potential in my lifetime . Of course last year ended up topping it. In 2010 OHX only recorded 7.1" of snow even with all of that cold. I had a little more at 9". It only seemed like a snowy winter because of the incredible snow drought leading up to it. Did you get a bunch of upslope that year? I do remember a bunch of trace events with very little accumulation.

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John1122

John1122

Posted
Posted

Wow! At the time I considered 2010 to be one of the biggest wastes of potential in my lifetime . Of course last year ended up topping it. In 2010 OHX only recorded 7.1" of snow even with all of that cold. I had a little more at 9". It only seemed like a snowy winter because of the incredible snow drought leading up to it. Did you get a bunch of upslope that year? I do remember a bunch of trace events with very little accumulation.

 

I had a strange synoptic event that produced snow over only Campbell county and rain in all other directions in early December 2009. I got 8 inches from that. I had another 13 inches on January 29th-30th. I had two 6 inch events in February, one I believe was from a super clipper. I think the balance was generally upslope/regular clippers.

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Mr Bob

Mr Bob

Posted
Posted

Pretty sure he was being sarcastic valk

Yup...and now the persimmon seeds are showing all spoons...E TN will be an arctic desert by mid January this year.

 

The late January 2010 5-6" event was a nightmare...it was a touch and go event the whole time only fully becoming evident that day as the temp dew point spread was so wide that the change over was too late...it all fell in the early afternoon so it was about the worst commute home I have had...A very light rain fell through the evening and it was basically gone Saturday. It was one of my least favorite snow events ever.

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