Feb 12-13 Sleet/Snow/ZR Event

[Shawn]

Alright.  I just took a glance this morning.  Euro EPS is getting on board quite heavily.  Many members show accumulating snow into the upstate of SC.  Some are even getting on board for the Midlands for the 12/13th timeframe.

 

Some of the larger amounts from the op in SC (10+ inches) are a bit overdone I believe.. and the EPS mean is around 2 inches though.

 

If the 12z holds on to it, I'll see if I can find some time to get some EPS member #s.

 

 

The point is, the GFS has been hinting.  And now the EPS members are jumping on.  Always a good sign!  The EPS didn't really do much for the first event that is gonna flop possibly.

[BullCityWx]

0z Euro looks like a classic charlotte winter storm. Front end snow thump followed by sleet and ending as a little freezing rain/drizzle.

[strongwxnc]

The 6GFS, as stated above, cuts down on totals. However, at least for KFQD, the 850's are at or below 0 for Wednesday and Thursday.  But the 6 is showing light totals around. But Calc, that map looks nice..

Look at this beautiful snow map off the Euro out at hour 162 on Wednesday.  This is the same time as the GFS has been showing.

 

 

 

Edit:  Sorry I didn't see that we had ballooned to a couple more threads overnight...

[Shawn]

0z Euro looks like a classic charlotte winter storm. Front end snow thump followed by sleet and ending as a little freezing rain/drizzle.

 

45+/50 00z EPS members support winter weather in Charlotte, NC.

 

The op's is 8-9 inches and the EPS mean says a little over 4.

 

Not sure if the EPS is factoring in "ice" as snow; but that's what I see.

 

Looking highly likely for CLT.

[SnowNiner]

Wow, looks like great model runs over night.  Perhaps the models feel bad for playing us like a trombone for this weekend.  Maybe.  Really hoping for the EURO solution.  Not looking forward to another December 2002 for CLT. 

[Cold Rain]

Shocked no one has posted the Dgex. Massive, massive hit!

[packfan98]

Enjoy your fantasy snow!

[burgertime]

Shocked no one has posted the Dgex. Massive, massive it!

 

   

[lilj4425]

Enjoy your fantasy snow!

I only get 18 inches.

[packfan98]

In all honesty, the track of the low on the DGEX looks to be in line with the 0z gfs and Euro runs from last night.

[Cold Rain]

 

I only get 18 inches.

 

Me too. Thanks for posting it!

[burgertime]

As Larry points out often I'm not sure how the Euro is putting out so much snow. 0 850 line is never south of CLT and looks like it only gets close for 6 hours max when precip is moderate at best. 540 line is well into VA for thickness conducive to snow.  I know it's pointless looking at finite details like that right now....just keep those things in mind with the Euro is spitting out so much snow for this area. 

[NC_WX10]

Enjoy your fantasy snow!

I think that would set back my high school baseball season a bit!!

[SnowNiner]

   

 

 

Perhaps there's an algorithm for the DGEX run....when showing less than 12 inches of snow for an area = < 5% probability of snow.  However over 2 feet, > 75% of 1-3 inches in that area.  Seems reasonable right? 

 

 

As Larry points out often I'm not sure how the Euro is putting out so much snow. 0 850 line is never south of CLT and looks like it only gets close for 6 hours max when precip is moderate at best. 540 line is well into VA for thickness conducive to snow.  I know it's pointless looking at finite details like that right now....just keep those things in mind with the Euro is spitting out so much snow for this area. 

 

Yeah I'm watching that blue line, and it ain't where it needs to be for CLT.  I'm hoping not only the track stays nice but the HP trends stronger to keep it colder.  I'm thinking if this pans out it's going to be mostly sleet/freezing rain for CLT.  I-40N I think has a good chance of seeing a good amount of snow right now though.

[rduwx]

As Larry points out often I'm not sure how the Euro is putting out so much snow. 0 850 line is never south of CLT and looks like it only gets close for 6 hours max when precip is moderate at best. 540 line is well into VA for thickness conducive to snow.  I know it's pointless looking at finite details like that right now....just keep those things in mind with the Euro is spitting out so much snow for this area. 

 

I agree burger...The same goes for RDU.  The 0z euro was a lot of rain for the rdu area.  The track on the euro was a little NW and the high scooted east off the coast rather than north like the gfs was showing.

[GaWx]

Here's one of the frames from the Wunderground map of the Euro last night. I mistakenly placed this in the pattern thread originally, not seeing that we had started umpteen different threads overnight. 850s seem pretty supportive of snow for at least the more northern portions of this map, so it's a pretty decent thump:

The Euro clown maps are always way overdone when there are locations getting significant amounts of IP and especially ZR as they normally assume 10:1 ratios for ALL wintry precip. Example: NE GA and upstate SC are definitely not getting 10-12" of snow on this run lmao. Then again, why it doesn't show CLT with 20" is beyond me.

Edit: I think I figured out why CLT doesn't get 20". It is because this map only goes through 18Z on 2/12.

[GaWx]

45+/50 00z EPS members support winter weather in Charlotte, NC.

 

The op's is 8-9 inches and the EPS mean says a little over 4.

 

Not sure if the EPS is factoring in "ice" as snow; but that's what I see.

 

Looking highly likely for CLT.

Shawn,

The individual Euro ensemble members also count ZR as snow 10:1.

[Heisy]

Be very wary of this storm, a lot of the models have the southern vort eventually phasing with a piece of energy coming out of Canada. If the southern vort is too slow, they will phase and it will likely be a rain solution for many on the East Coast. The DGEX is a perfect run because the southern vort is fast enough that it doesn't phase until too late. 

[calculus1]

The Euro clown maps are always way overdone when there are locations getting significant amounts of IP and especially ZR as they normally assume 10:1 ratios for ALL wintry precip. Example: NE GA and upstate SC are definitely not getting 10-12" of snow on this run lmao. Then again, why it doesn't show CLT with 20" is beyond me.

 

Understood, Larry.  Your posts and those of Shawn have been very enlightening regarding that matter.  However, it does show the general location of wintry precipitation quite well, and it would be largely snow for those areas north of I-40, for instance.  Oh, and the reason it doesn't show 20" for Charlotte is because it's simply a 6-hour accumulation map, not a storm total figure.  They get more, not 20" obviously, on other frames.

[RevDodd]

Enjoy your fantasy snow!

Meh! Only 18-21 inches at the chateau ...

[Pilotwx]

This about the same time frame as our Sunday epic snowfall fell to pieces. Don't get your hopes to high great runs so far.

[Southern Track]

Be very wary of this storm, a lot of the models have the southern vort eventually phasing with a piece of energy coming out of Canada. If the southern vort is too slow, they will phase and it will likely be a rain solution for many on the East Coast. The DGEX is a perfect run because the southern vort is fast enough that it doesn't phase until too late.

I thought what we have seen so far is not an issue with a phase, but with how sharp the trough is. The 0z. Euro and GFS had a nice sharp trough, while the 6z GFS was more zonal and thus showed a weaker storm?

I could be wrong though.

[Heisy]

I thought what we have seen so far is not an issue with a phase, but with how sharp the trough is. The 0z. Euro and GFS had a nice sharp trough, while the 6z GFS was more zonal and thus showed a weaker storm?

I could be wrong though.

 

Image of what I mean, if the EURO was a bit faster and farther east with the shortwave down south it would of been a much snowier solution for most, but by the time the vort starts coming up the coast the HP has slid East and heights are rising. 

 

Note the difference in spacing (also look at the 6z DGEX)

 

00z GFS;

 

00z EURO:

[Heisy]

Note the difference in timing between the EURO & GFS on the map I posted. The 6z DGEX runs that southern vort far out ahead of that Canadian energy. Not only does the less phasing help, but it also takes advantage of the cold HP to the north before it is kicked East. 

[GaWx]

Understood, Larry. Your posts and those of Shawn have been very enlightening regarding that matter. However, it does show the general location of wintry precipitation quite well, and it would be largely snow for those areas north of I-40, for instance. Oh, and the reason it doesn't show 20" for Charlotte is because it's simply a 6-hour accumulation map, not a storm total figure. They get more, not 20" obviously, on other frames.

Thanks, Calc. Yeah, I later figured out that the map was for 18z on 2/12 and edited my post although I didn't know it was only for 6 hours worth. Oh yeah, 10-12" of snow for NE GA/upstate/SW NC over only a six hour period. Yeah, right, that's reasonable lmao. These maps are almost comical because I assume many people still have no idea about the inaccurate algorithm.

OTOH, you're right that it shows the general area of wintry precip. nicely and can give a pretty good idea of the forecasted total wintry qpf although I'm not so sure it doesn't also overdo wintry qpf.

[Southern Track]

Note the difference in timing between the EURO & GFS on the map I posted. The 6z DGEX runs that southern vort far out ahead of that Canadian energy. Not only does the less phasing help, but it also takes advantage of the cold HP to the north before it is kicked East.

Makes sense, thanks for the illustration.

[Lookout]

The Euro clown maps are always way overdone when there are locations getting significant amounts of IP and especially ZR as they assume 10:1 ratios for ALL wintry precip. Example: NE GA and upstate SC are definitely not getting 10-12" of snow on this run lmao.

I don't know why anyone ever posts these euro snow maps. They are so far from reality that you could give some crayons to a 5 year old and they would make a map just as "accurate". Every single time it shows wayyy to much or snow when the temp profile is clearly not supportive of it..hell not even close to supportive of it.

 

At any rate, the euro is able to slide the high into position fairly early. the gfs and canadian do not do this. However, the gfs ensembles, for the most part, agree with the euro in the high moving into position earlier. It looks like it's almost a lock (if there is a storm) given the model agreement that nc is going to get snow and ice, just depends on how much. The real question is what happens in north ga and the upstate.

 

I have never known the euro to ever get surface temps right in cad situations. It's usually 2 to as much as 5 degrees too warm. If it is that far off this time, there is probably ice down into at least northeast ga. (of course it's been so long since there has been one, I'm not sure if that still applies lol) But  IF the high is in position that soon and IF it's as strong, I think odds favor a colder solution further south. It's interesting to note though, the euro has the low quite a bit further north than the gfs.

 

As for the gfs, it's much less favorable further south for several reasons. One is it's high does not move into position as early as the euro. I can't see the surface winds but the euro is a good bit faster than the gfs in getting that high into a favorable position. Second,  The gfs also has it's parent high  4 or 5mb weaker with it by the time it does get into place. Third, The gfs's high is "strung out" and instead just has a broad area of weak high pressure. The euro on the other hand has a much more defined high. These are crucial elements in determining if freezing temps and lower dewpoints/wetbulbs  can make it south of nc and especially ga.

 

So in order for ice to happen here, we really need that high in place a good 12 to 18 hours (at least) but preferably 24 hours ahead of time in order for their to be enough colder and drier air to make it far enough south. From my experience, it's really rare in georgia and to a lesser extend the upstate  for temps to start off above freezing after wetbulbing and it end up below freezing with significant freezing rain. Almost always you have to have the cold and drier air in place before hand. It's not nearly as hard though in north carolina but of course it's preferable. But that doesn't seem to be a problem there, no matter what guidance you look at.

 

On other note, and this is just a general rule of thumb from past experience, is that if 850mb temps start off at or below freezing down into south carolina or northeast ga in a CAD situation, freezing temps/significant ice is much more likely in ne ga and the upstate than if it's up near the nc/va border (regardless of how cool they are here). In other words, even if 850mb temps are only 2 to 4c here, which is normally a good temp to have for freezing rain in cad situations, it's not nearly as likely if the 0c isotherm is up near the nc/va border to start with. 0z gfs has it well to the north while the 06z run is border line, having it touch the sc line. But if it's more like the euro, which has it actually into northeast ga when precip first starts or right before it, then ice is much more likely in northeast ga and of course the upstate.

 

Overall, if you are in north carolina, you should feel pretty good about your chances. In the upstate, you should probably be more hopeful than not to see winter precip, while in northeast ga one should not have expectations of getting much as of right now.

 

This is of course dependent on if there is an actual storm and it takes the general path laid out by the models in general. It's far enough out that it obviously could change drastically still.

[burgertime]

Image of what I mean, if the EURO was a bit faster and farther east with the shortwave down south it would of been a much snowier solution for most, but by the time the vort starts coming up the coast the HP has slid East and heights are rising. 

 

Note the difference in spacing (also look at the 6z DGEX)

 

00z GFS;

gfs168.gif

 

00z EURO:

140206143742393081000.gif

 

Great synopsis. As usual the DGEX is the most extreme solution. Interestingly enough the 00z GFS from last night wasn't too far off at 500mb with the energy coming in on the back side from the north. There are some ENS members from last night which show a really big hit for the upstate and NC. So it's to throw the DGEX out but it is certainly possible for that solution. Of course I doubt we get 30 inches of snow but we can dream I suppose. 

[Cold Rain]

Southern stream wave looks weaker on the 12z at 114 than on the 0z at 126.

[burgertime]

Southern stream wave looks weaker on the 12z at 114 than on the 0z at 126.

 

Yep kind of puts it in the meat grinder and lets it just sit there for 12 hours. It's starting to move now at 129 but don't think it's going to cut it.