Mid to Long Term Discussion 2018

[Upstatescweather]

Well I see where Mr.justice just showed the euro vs the gfs and said things could get very interesting or we could have absolutely nothing  but rain. 

[ajr]

2 minutes ago, packfan98 said:

Yep!  The low tracked pretty much due east instead of cutting.  Many ensembles have had a similar look. Here's the overblown clown map:

Looks to me like it spins off another low?

[packfan98]

1 minute ago, ajr said:

Looks to me like it spins off another low?

 

A hybrid Miller A/B I think with the low taking a beating cutting across the CAD region.

[kvegas-wx]

17 minutes ago, WidreMann said:

You thinking of the December 8th event?

Dont think that was it Widre because we were in the 40's and 50's leading up to that at KGSO.  No HP in place pre-storm.  This event as modeled has the HP in place starting on Friday.  I agree with Buddy, I think this has to end up a slider if that banana HP is parked and cant understand why the GFS wants to run these systems into a brick wall.

[Wow]

FV3 is a big snow/ice event for WNC.  CAD holding on with miller B setup

[Wow]

27 minutes ago, packfan98 said:

Yep!  The low tracked pretty much due east instead of cutting.  Many ensembles have had a similar look. Here's the overblown clown map:

Pretty much everyone outside of the foothills will have a transition to ice as storm moves through, verbatim.

[Buddy1987]

33 minutes ago, kvegas-wx said:

I swear I rememeber we had a similar setup last year where the GFS depicted this exact outcome and the board chatter was identical..  We did end up with a winter event, but cant recall the outcome.  Ring a bell with anyone else, and if so, any similarities?

I feel like I can name more than a handful of times the model has done this. But yes it def rings a bell from last year and then kept adjusting closer to game time. 

 

On a side note, FV3 is an absolute beauty and much more realistic with the players. Primary into northwestern most portions of Alabama, then transferring energy just off myrtle, solidifying the locking in the cold air for a lot of us. This system has that classic setup that is almost textbook to a major cad event for the forum, whereas its one of those things the model signals, like we’ve seen in years past, picks up a storm at over 10 day lead time and just fine tunes as the system nears. The threat is legitimate at this point, regardless of how far out it is. I’m pretty impressed with the signal that has been run after run. 

[Buddy1987]

14 minutes ago, kvegas-wx said:

Dont think that was it Widre because we were in the 40's and 50's leading up to that at KGSO.  No HP in place pre-storm.  This event as modeled has the HP in place starting on Friday.  I agree with Buddy, I think this has to end up a slider if that banana HP is parked and cant understand why the GFS wants to run these systems into a brick wall.

Imo, as this event draws closer, the banana highs from previous experience tends to strengthen. It is formidable a lot of times when these things form and the models pick up on them. I think that is why some of the guys in the mid Atlantic forum are a little nervous for it to end up further south than progged come verification time. I know some of the Mets I talk to have acknowledged they know this is a tendency for the gfs to do this in past events, only to cave and adjust. I know I keep stating it but it is something the GFS always has a hard time with (CAD in general). 

[CAD_Wedge_NC]

34 minutes ago, ajr said:

Looks to me like it spins off another low?

 

That's a common miller B transfer of energy to the coast. Ideally, you want that transfer to take place south of you as shown. That will keep the cold air locked in and you will not lose that fresh feed of cold air. We have had some all-snow events with a set-up like this, but those were associated with colder air masses. Most of the time in these situations, there is some degree of mixing during the storm.

[Waiting on snow]

1 hour ago, Waiting on snow said:

It's time for the FV3 to get on board and prove it's way better than the garbage GFS we are used to. 

And right on schedule it joins the party!

[Buddy1987]

18z GEFS is worlds difference from the OP and def supports a better overall track. 

 

Almost all the members have a solid track. One or two run it up into WV but most obv realize the strength of the double structured high pressures.

[Waiting on snow]

1 hour ago, packfan98 said:

Yep!  The low tracked pretty much due east instead of cutting.  Many ensembles have had a similar look. Here's the overblown clown map:

How does it come up with that in SC? By tropical tidbits SC sees rain the whole time.

[CAD_Wedge_NC]

2 minutes ago, Waiting on snow said:

How does it come up with that in SC? By tropical tidbits SC sees rain the whole time.

Who knows..... It's obviously flawed. No way my area sees over 20 inches of snow. I haven't looked at the QPF to see if it even has that much precip falling in the storm. 

[calculus1]

How does it come up with that in SC? By tropical tidbits SC sees rain the whole time.

Who knows how all these algorithms actually process the information to produce these "snow" maps? But, IMO, the only part of SC that has any realistic shot at snowfall would be the upstate, like usual. And none of us, NC and VA included, should get too hyped at this point. I love all the trends and the signals, but this is early in the season and still so far out that we can't accurately predict anything with any confidence. Let's keep it all in moderation, guys, and not get too insane with our posts. I so appreciate the sound, reasonable meteorology, but I could do without the crazy, unfounded gut feelings.

Sent from my Alcatel 6055U using Tapatalk

[strongwxnc]

Who knows..... It's obviously flawed. No way my area sees over 20 inches of snow. I haven't looked at the QPF to see if it even has that much precip falling in the storm. 

Wait, this map is not correct...

I would also love to understand how this output occurred.

Now, how many days out....

 

 

.

[ryan1234]

Who knows..... It's obviously flawed. No way my area sees over 20 inches of snow. I haven't looked at the QPF to see if it even has that much precip falling in the storm. 

While I agree with you, never say never. It was last year, around the same time, that the northern Atlanta burbs got over a foot of snow. Yes, the odds of anyone seeing that amount are slim to none, it doesn’t mean it isn’t plausible. Quite frankly, I’m just happy to be tracking a winter storm in early December. Regardless of the outcome, it’s pretty exciting.


.

[jburns]

3 hours ago, FallsLake said:

Not bad for RAH this far out:

It will otherwise be colder through the end of the week, as the trough aloft and cP high pressure migrate ewd across the srn Appalachians and sern US - coldest Thu, when highs will be in the 40s and lows solidly in the 20s. A reinforcing cold front, and leading edge of a fresh cP high, will then move swd through VA/NC late Fri-Fri night, immediately ahead of a significant srn stream wave and next bout of precipitation next Sat. This system will bring with it a good chance of a widespread, soaking rain, and also a threat of wintry weather at least at the onset over the Piedmont, as the srn stream moisture moves newd and interacts with the cP high.

I put no stock in any long-range forecast that has snow in Raleigh.  Raleigh usually doesn't know if it will be rain or snow an hour before precipitation starts.

[BornAgain13]

I know we are still far out folks, but what is almost certain is, that their will be a storm. Nailing down the specifics will be interesting as we get closer.

[Waiting on snow]

4 minutes ago, calculus1 said:

Who knows how all these algorithms actually process the information to produce these "snow" maps? But, IMO, the only part of SC that has any realistic shot at snowfall would be the upstate, like usual. And none of us, NC and VA included, should get too hyped at this point. I love all the trends and the signals, but this is early in the season and still so far out that we can't accurately predict anything with any confidence. Let's keep it all in moderation, guys, and not get too insane with our posts. I so appreciate the sound, reasonable meteorology, but I could do without the crazy, unfounded gut feelings.

Sent from my Alcatel 6055U using Tapatalk
 

I understand it takes all frozen at 10:1 and shows snow. But SC doesn't even get freezing rain by the exact same model.

[POWERSTROKE]

14 minutes ago, CAD_Wedge_NC said:

Who knows..... It's obviously flawed. No way my area sees over 20 inches of snow. I haven't looked at the QPF to see if it even has that much precip falling in the storm. 

Always figure half of what accumulation map shows and that will be just fine with me

 

[SENC]

2 hours ago, packfan98 said:

Yep!  The low tracked pretty much due east instead of cutting.  Many ensembles have had a similar look. Here's the overblown clown map:

south 75~100 miles please..  Or the "secondary Low" too "overperform"  

[CaryWx]

59 minutes ago, BornAgain13 said:

I know we are still far out folks, but what is almost certain is, that their will be a storm. Nailing down the specifics will be interesting as we get closer.

I agree with BornAgain.  We have a storm.  Details to come 

[SENC]

Like to see this again.. Edit excited about "possible chances with the secondary low" 

[SENC]

2 hours ago, kvegas-wx said:

I swear I rememeber we had a similar setup last year where the GFS depicted this exact outcome and the board chatter was identical..  We did end up with a winter event, but cant recall the outcome.  Ring a bell with anyone else, and if so, any similarities?

yes,,  We did  get  this?.. high 60's & low 70's,,  Did I win the chicken/oyster dinner? (EDIT) We, well I on  the coast have the same conditions as last year.. We already have had "several" thunder events, (Including today/tomorrow),  Same set-up (almost).. ? Went SST fishing, yesterday,  (speckled sea  trout) fishing the bite was off the hook literally, same as last year before the above event.. 

[Wow]

This time last year.  Yes, we had a storm early December last year:

[SENC]

5 minutes ago, Wow said:

This time last year.  Yes, we had a storm early December last year:

You dynamiting my hopes.. By 30 days.. I'm going by the fishing bite, (if you don't mind) Fish don't lie.. Squirrels are ravaging my area.. Of course there's NO nuts, acorns etc fell due to Florence, so there's that..

Sorry "WOW" I look at natures signs..  

[griteater]

1 hour ago, Waiting on snow said:

How does it come up with that in SC? By tropical tidbits SC sees rain the whole time.

weathernerds.org by Matt Onderlinde has a more advanced precip type algorithm than most I believe - https://twitter.com/Weathernerds/status/1052935035379167232

Here's his description of the precip type field - 

"“Precip Type” on weathernerds.org refers to the type of precipitation forecast to occur at ground level at the time in question (i.e., not averaged over the past HH hours, but rather at the forecast time). The precipitation type is computed (during Weathernerds data ingest) from the model fields using accumulated precipitation and temperature at all vertical levels. In other words, this is not just the dominant precipitation type output from the model (which typically IS averaged over the past HH hours). Five possible types are computed: rain, snow, sleet, freezing rain, or mix. Mix may consist of a mixture of multiple categories but usually refers to rain/snow mix. Users are encouraged to generate soundings in these locations to verify which type is occurring in the model. Rain/snow mix is plotted when the the above-ground freezing level is between 1500 and 2000 feet (457 – 610 m). Snow is plotted when the freezing level is below 1500 feet and rain is plotted when the freezing level is above 2000 feet. Areas where no precipitation is forecast are marked as missing data and are not plotted."

Here's what he has for the 18z run of the FV3:

[griteater]

^ He also has an advanced algorithm for snowfall...but having said that, his clown map for the FV3 is inflated like TTidbits where there is mixed precip, so something is off there.

https://www.weathernerds.org/models/field_definitions/Snowfall.pdf

[griteater]

Here's the 500mb trend on the last 3 runs of the 12z EPS Mean when our storm wave is in a similar location over the southern plains.  Note the trend in the height lines over northern Ohio / NY State / Pennsylvania - the height lines are trending from westerly to more west-northwest.  That subtle difference is a key trend and a good trend for acting to keep our storm wave and associated surface low on a bit of a more southerly track, yielding a colder and more wintry solution for parts of our subforum.  In contrast, if these height lines over NY state trend from westerly to more west-southwesterly, that opens the door for the storm to climb north.  There is a bit more ridging poking into Greenland which helps as well (all subtle differences that are key).

[olafminesaw]

19 minutes ago, griteater said:

^ He also has an advanced algorithm for snowfall...but having said that, his clown map for the FV3 is inflated like TTidbits where there is mixed precip, so something is off there.

https://www.weathernerds.org/models/field_definitions/Snowfall.pdf

There's also a lot of borderline soundings, where his algorithm is counting as snow, but there's no point splitting hairs at this point. When it comes down to forecasting closer to the event, it's probably better not to rely on snow maps, but do qpf frame by frame with precip type based on soundings.