The Official 2014 Fall Discussion Thread

[NEGa]

this "not impressive" cold here was 19 last night and havent hit 32 yet today.  and this is mid november lol

 

i would be overjoyed with these temps in january!

[jshetley]

This cold shot is impressive for sure, especially for daytime highs. It didn't reach 40 here and it's only November 18. I can remember a couple of entire winters without a high temp below 40 here.

[LithiaWx]

18Z GFS OP looks a bit interesting.  Pretty potent cold shot on Thanksgiving, it looks transient but it's cold, with a weak system off the NC coast. 

 

 

[LithiaWx]

but it's in and out and literally that is the only bright spot on the entire run. 

[metwannabe]

but it's in and out and literally that is the only bright spot on the entire run.

Then come on back for 00z and you will SE a run thats 100% different

[LithiaWx]

Then come on back for 00z and you will SE a run thats 100% different

 

Probably not considering it was almost a carbon copy of the 12Z run.  Things will change but a steady warm up between now and thanksgiving looks almost certain.  There will probably be a cool to cold shot around Thanksgiving, that's also pretty much certain.  The cold will be a quick hitter, also nearly certain.  Past Thanksgiving things become less clear imo.

[metwannabe]

Probably not considering it was almost a carbon copy of the 12Z run. Things will change but a steady warm up between now and thanksgiving looks almost certain. There will probably be a cool to cold shot around Thanksgiving, that's also pretty much certain. The cold will be a quick hitter, also nearly certain. Past Thanksgiving things become less clear imo.

Lol just cause it was similar to 12z means a hill of beans in regards to what the 00z will look like. I find it interesting your using words like certain when speaking of the long range

[LithiaWx]

Lol just cause it was similar to 12z means a hill of beans in regards to what the 00z will look like. I find it interesting your using words like certain when speaking of the long range

 

btw the Euro Ensembles support the 12Z run which wasn't that kind to us.  We obviously agree to disagree.  I don't call 7-10 days long range.  You can get a general idea of what will happen in that time frame.  The GFS, Euro & Ensembles agree on where we are headed over the next 7 days or so, believe it or not but you can look at them yourself.  If you believe the models are wrong that's fine but they show what they show and it's pretty much exactly what I laid out.  When there is that kind of agreement it's hard to expect something different.  Again past Thanksgiving imo things do become less clear.   We agree to disagree ok?

[metwannabe]

btw the Euro Ensembles support the 12Z run which wasn't that kind to us. We obviously agree to disagree. I don't call 7-10 days long range. You can get a general idea of what will happen in that time frame. The GFS, Euro & Ensembles agree on where we are headed over the next 7 days or so, believe it or not but you can look at them yourself. If you believe the models are wrong that's fine but they show what they show and it's pretty much exactly what I laid out. When there is that kind of agreement it's hard to expect something different. Again past Thanksgiving imo things do become less clear. We agree to disagree ok?

Of course we agree to disagree ..... Btw for what it's worth my opinion is 7-10 is the LR . It changes almost every run on both models and you mentioned the ensembles which have been all over the place lately so it is what it is. I'm not arguing a brief warmup at all my point was to your first comment and all I said was 00z would look different . But yes we agree to disagree

[CAD_Wedge_NC]

Of course we agree to disagree ..... Btw for what it's worth my opinion is 7-10 is the LR . It changes almost every run on both models and you mentioned the ensembles which have been all over the place lately so it is what it is. I'm not arguing a brief warmup at all my point was to your first comment and all I said was 00z would look different . But yes we agree to disagree

  Agree 100%.... It is not wise to look beyond 5 days this time of year. The ensembles will give you a general idea of what could happen, but they are far from certain. I am solidly in the cold camp for winter as a whole, but I do expect some stretches of above normal temps. As a side note, I highly respect Robert's pattern recognition skills. Right now, I would not bet against him. Bottom line is..... hold on to your hats folks. This is just the beginning of a great winter for the SE peeps.

  If this winter turns out to be warmer than normal, we can deem all of our pre-winter analogs and indices worthless and just go back to now-casting. There is just too much data supporting a cold winter.

[calm_days]

I don't know which topic to post this in, so I'll throw this out in here...

 

Is anyone else surprised that despite all these cold surges, very strong fronts, and radical temperature plunges, the SE has pretty much avoided their second 'severe storm/tornadic season'? I'm not complaining at all, but it seems unusual that we haven't really had to deal with any significant severe weather this fall.

 

Thunderstorm patterns visually appeared very different this year, although, if there was radar/satellite imagery from enough earlier decades maybe some analogs could be found. 

 

This spring and summer for the continent, it was most often thunderstorms as part of very large pockets of moisture that on satellite imagery were often the size of tropical cyclones though not always with comparable wind and severe energy to them; including the area which did turn into the Arthur cyclone.  Once that ended the overall presence of thunderstorms seemed to diminish.  It does seem like as weather itself evolves, what could seem like guaranteed patterns can shift into something different that can either stay for a year or two or adjust again into something else new.

[FallsLake]

6z GFS is definitely interesting for Black Friday and the following Saturday:

 

http://mag.ncep.noaa.gov/Image.php?image=data%2Fgfs%2F06%2Fgfs_namer_240_850_temp_mslp_precip.gif&model=gfs&area=namer&storm=&cycle=06&param=850_temp_mslp_precip&fhr=240&group=Model+Guidance&imageSize=M&ps=model&use_mins=no&preselected_formatted_cycle_date=20141119+06+UTC&scrollx=0&scrolly=0

[FallsLake]

For what it's worth:

 

http://www.twisterdata.com/index.php?prog=forecast&model=GFS&grid=3&model_yyyy=2014&model_mm=11&model_dd=19&model_init_hh=06&fhour=240&parameter=SNOWIN&level=SURFACE&unit=none&maximize=n&mode=singlemap&sounding=n&output=image&view=large&archive=false

[Brick Tamland]

For what it's worth:

 

http://www.twisterdata.com/index.php?prog=forecast&model=GFS&grid=3&model_yyyy=2014&model_mm=11&model_dd=19&model_init_hh=06&fhour=240&parameter=SNOWIN&level=SURFACE&unit=none&maximize=n&mode=singlemap&sounding=n&output=image&view=large&archive=false

 

 

Well, it would be funny if the first snow in my backyard comes while I am down in Florida visiting Mickey Mouse. 

 

On second thought, it wouldn't be funny. 

 

Since it's showing on the model 10 days out can we say it's certain?

[LithiaWx]

Well, it would be funny if the first snow in my backyard comes while I am down in Florida visiting Mickey Mouse. 

 

On second thought, it wouldn't be funny. 

 

Since it's showing on the model 10 days out can we say it's certain?

 

Twisterdata snow maps

[metwannabe]

Well, it would be funny if the first snow in my backyard comes while I am down in Florida visiting Mickey Mouse.

On second thought, it wouldn't be funny.

Since it's showing on the model 10 days out can we say it's certain?

What if snowed why you were gone and it was the only one of the season?

[Brick Tamland]

What if snowed why you were gone and it was the only one of the season?

 

I think taking the kids to Disney for the first time would be worth missing it.

[calculus1]

Well, it would be funny if the first snow in my backyard comes while I am down in Florida visiting Mickey Mouse. 

 

On second thought, it wouldn't be funny. 

 

Since it's showing on the model 10 days out can we say it's certain?

 

If snow falls from the sky, but no one is there to see it, does it stick? 

[superjames1992]

If snow falls from the sky, but no one is there to see it, does it stick? 

 

No, because the scorching November sun angle melts it all before it reaches the ground. 

 

Snow can only fall and accumulate in the southeast during the two weeks around the winter solstice.  Any other time and it's a scorcher. 

 

EDIT: This post is not serious!

[CAD_Wedge_NC]

No, because the scorching November sun angle melts it all before it reaches the ground. 

 

Snow can only fall and accumulate in the southeast during the two weeks around the winter solstice.  Any other time and it's a scorcher. 

 

The sun angle now is the same as it would be in late January. Sun angle is not a problem.

[LithiaWx]

The sun angle now is the same as it would be in late January. Sun angle is not a problem.

 

Whoosh!

 

In all seriousness though sun angle and ground temps "theory" have been disproven about as many times as the 6Z & 18Z runs being less accurate than the 12z & 0Z runs.  If it snows hard enough neither of those factors matter.  Snow can accumulate in late April if it snows hard enough.

[superjames1992]

The sun angle now is the same as it would be in late January. Sun angle is not a problem.

 

I know.  It was a joke.

 

Hence my second line, which is obviously demonstrably not true: "Snow can only fall and accumulate in the southeast during the two weeks around the winter solstice. Any other time and it's a scorcher."

 

Hell, it snowed and accumulated during the day in mid-March here last year.

[Cold Rain]

Snow rate trumps all other factors while the snow is falling.  If you've got warm ground temps, it does help the melting process...especially on the roads.  But if it's coming down hard enough, it's going to pile up and the roads will be a mess.

[superjames1992]

Whoosh!

 

In all seriousness though sun angle and ground temps "theory" have been disproven about as many times as the 6Z & 18Z runs being less accurate than the 12z & 0Z runs.  If it snows hard enough neither of those factors matter.  Snow can accumulate in late April if it snows hard enough.

 

I think sun angle and ground temperatures are legitimate issues depending on the situation.  I think surface temperatures are an underrated aspect of it, too, though.  Snow falling during the day in March with warm group temperatures, but an air temperature of 21 degrees would probably stick.

 

However, the trifecta of screwage with BL temperatures of 33-34 degrees, warm ground temperatures, and a higher sun angle can screw you over if the snow isn't hard enough.  Obviously, if the snow is heavy, it's not going to matter as much (though there still will be melting underneath).

 

Snow rates are very important as we get later into winter and the sun angle and soil temperatures become more of an issue.

[superjames1992]

Snow rate trumps all other factors while the snow is falling.  If you've got warm ground temps, it does help the melting process...especially on the roads.  But if it's coming down hard enough, it's going to pile up and the roads will be a mess.

 

Indeed.

 

Soil temperatures aren't irrelevant, though.  NWS RAH typically brings up soil temperatures in their case studies of various winter storms because they do have an effect on what accumulates (and especially on roads, as you mention), especially if rates are not heavy.

 

It's not really something I worry about during legitimate winter storms because in those situations rates will likely be heavy enough to make it a moot point, but during more marginal events, it can matter.

[LithiaWx]

True, but snow on 12/25 a couple of years ago couldn't accumulate because it wasn't falling hard enough even though it snowed ALL day.  That's about as low a sun angle as you can get.  I do agree that ground temps, soil temps, and sun angle are all factors but they take a back seat to snowfall rates.

[CAD_Wedge_NC]

Whoosh!

 

In all seriousness though sun angle and ground temps "theory" have been disproven about as many times as the 6Z & 18Z runs being less accurate than the 12z & 0Z runs.  If it snows hard enough neither of those factors matter.  Snow can accumulate in late April if it snows hard enough.

 

No!, it did not go over my head.....I understood that he was being facetious. I just wanted to dispel any myths about the sun angle this time of year. 

[superjames1992]

True, but snow on 12/25 a couple of years ago couldn't accumulate because it wasn't falling hard enough even though it snowed ALL day.  That's about as low a sun angle as you can get.  I do agree that ground temps, soil temps, and sun angle are all factors but they take a back seat to snowfall rates.

 

Were BL temperatures above freezing?  I find that can be a real killer that is often overlooked.

 

Last year we had a couple storms with snow and temperatures in the low 20s and upper 10s.  I never realized how much that helps (seems like it's been years since we've had snowstorms with temperatures so cold).  The January 28th storm only had light snow, but it actually stuck to the roads during the day because it was so damn cold (18-19 degrees).  The February big dog event also stuck in the middle of the afternoon almost instantly to everything (heavy snow, though) with temperatures in the low 20s.  The snow that stuck in mid-March during the day also came with temperatures in the mid-20s.

 

I think I'm really going to be rooting for cold BL temperatures during storms this winter.

[LithiaWx]

Were BL temperatures above freezing?  I find that can be a real killer that is often overlooked.

 

Last year we had a couple storms with snow and temperatures in the low 20s and upper 10s.  I never realized how much that helps (seems like it's been years since we've had snowstorms with temperatures so cold).  The January 28th storm only had light snow, but it actually stuck to the roads during the day because it was so damn cold (18-19 degrees).  The February big dog event also stuck in the middle of the afternoon almost instantly to everything (heavy snow, though) with temperatures in the low 20s.  The snow that stuck in mid-March during the day also came with temperatures in the mid-20s.

 

I think I'm really going to be rooting for cold BL temperatures during storms this winter.

 

Yep it was probably 33-35 all day while snowing if I remember right.  I do think BL temps play a huge role as you state.

[jburns]

It is rare that we have storms in the SE with heavy snow rates for an extended period of time, and that's what it takes to build accumulations when other conditions are less than optimal.  Snow rate can trump all else, but it has to be consistent. A rate of 2 inches per hour for 20 minutes followed by 40 minutes of light snow won't get the job done. That's how we end up with "snowstorms" that last all day with one inch of accumulation.  I've mentioned on here before, that the heaviest snow I've ever been in was the last week of April in SW Virginia.  The temp never went below thirty and almost all the accumulation was in the daytime.