Pre-Christmas Winter Storm Potential

[Chicago WX]

It could work if you're willing to travel for ice.

 

Possibly. But I'm moving my 33 and rain to there.

 

I have to drive up there on Sunday anyway. So the potential for "warm enough rain" is comforting, despite my weenie wanting wintry things. 

[Hoosier]

I suspect soundings would show there's significant mixing over my place but can't say for sure.

 

 

Could be since you're near the southern part of the heavy band on the clown maps.  Just south of you would be mixing galore for sure.

[harrisale]

I'll get text soon. When it updates I'll tell you.

 

Yes please share when you find it. Don't trust those weather bell maps for snow in these marginal situations and things are looking a little more ominous for YYZ now. Would love to see how the EURO models the temps in the 850-700mb range.

 

EDIT: GGEM gives us about 14 hours+ of ice.

[A-L-E-K]

Could be since you're near the southern part of the heavy band on the clown maps.  Just south of you would be mixing galore for sure.

 

 

That's what I was thinking but there's probably no need to get cute about it. That rain snow line has been steady marching north each run and i'll be firmly into the winter grab bag zone by 0z...on borrowed time.

[buckeye]

I like what I'm seeing hour 72....sw looks to hang longer over baja

[A-L-E-K]

wxbell gives you 14-15".

 

 

fyp

[A-L-E-K]

Buckeye isn't about to give up

[Chicago WX]

12z Kazakhstani run?

[KokomoWX]

ECMWF Deterministic FORECAST FOR: OKK LAT= 40.53 LON= -86.07 ELE= 830

12Z DEC17

2 M 850 SFC SFC 700 6 HR 500 1000

TMP TMP PRS RHU RHU QPF HGT 500

(C) (C) (MB) (PCT) (PCT) (IN) (DM) THK

TUE 12Z 17-DEC -9.8 -4.2 1020 86 49 0.00 538 522

TUE 18Z 17-DEC -5.8 -5.9 1018 84 97 0.00 534 520

WED 00Z 18-DEC -4.1 -9.0 1018 82 27 0.01 536 521

WED 06Z 18-DEC -7.0 -11.4 1021 78 28 0.00 544 528

WED 12Z 18-DEC -11.4 -5.5 1024 81 45 0.00 552 533

WED 18Z 18-DEC -7.4 0.0 1024 80 61 0.00 557 539

THU 00Z 19-DEC -1.9 3.8 1018 66 30 0.00 561 547

THU 06Z 19-DEC 1.1 5.3 1015 69 13 0.00 563 551

THU 12Z 19-DEC 2.4 4.8 1015 82 11 0.00 564 552

THU 18Z 19-DEC 4.8 4.2 1015 83 25 0.00 563 552

FRI 00Z 20-DEC 5.4 2.3 1014 86 28 0.00 563 551

FRI 06Z 20-DEC 7.1 4.3 1012 95 31 0.03 562 552

FRI 12Z 20-DEC 8.8 5.2 1010 98 54 0.11 560 552

FRI 18Z 20-DEC 8.9 5.2 1010 99 93 0.12 560 551

SAT 00Z 21-DEC 6.2 6.3 1010 99 57 0.08 560 551

SAT 06Z 21-DEC 4.0 4.0 1012 98 26 0.02 560 550

SAT 12Z 21-DEC 1.5 5.3 1015 93 58 0.00 561 549

SAT 18Z 21-DEC 4.2 7.9 1014 79 66 0.00 563 552

SUN 00Z 22-DEC 4.1 7.2 1010 97 99 0.39 564 556

SUN 06Z 22-DEC 2.1 11.6 999 97 97 0.98 561 562

SUN 12Z 22-DEC 2.0 7.3 1002 98 100 0.76 559 557

SUN 18Z 22-DEC 1.8 8.0 1000 97 21 0.65 557 557

MON 00Z 23-DEC 0.4 -2.2 1008 96 36 0.03 551 545

MON 06Z 23-DEC -1.5 -8.3 1017 89 76 0.01 546 533

MON 12Z 23-DEC -8.0 -12.1 1025 82 5 0.01 541 522

MON 18Z 23-DEC -9.7 -12.8 1030 72 16 0.00 537 514

TUE 00Z 24-DEC -15.2 -13.3 1035 77 3 0.00 544 518

TUE 06Z 24-DEC -14.9 -9.8 1037 75 6 0.00 557 529

TUE 12Z 24-DEC -18.5 -5.6 1035 77 2 0.00 561 535

ECMWF Deterministic FORECAST FOR: LAF LAT= 40.40 LON= -86.93 ELE= 607

12Z DEC17

2 M 850 SFC SFC 700 6 HR 500 1000

TMP TMP PRS RHU RHU QPF HGT 500

(C) (C) (MB) (PCT) (PCT) (IN) (DM) THK

TUE 12Z 17-DEC -9.8 -4.1 1020 85 65 0.00 539 523

TUE 18Z 17-DEC -5.7 -6.0 1019 83 93 0.01 534 520

WED 00Z 18-DEC -2.9 -9.3 1019 76 63 0.01 538 523

WED 06Z 18-DEC -6.9 -8.5 1022 75 26 0.00 547 530

WED 12Z 18-DEC -11.9 -4.0 1025 81 63 0.00 554 535

WED 18Z 18-DEC -6.6 0.4 1024 76 48 0.00 559 541

THU 00Z 19-DEC -0.6 5.1 1017 64 27 0.00 563 549

THU 06Z 19-DEC 1.7 5.8 1015 70 11 0.00 564 551

THU 12Z 19-DEC 2.9 5.1 1014 83 11 0.00 564 553

THU 18Z 19-DEC 4.8 4.2 1014 84 26 0.00 564 552

FRI 00Z 20-DEC 5.3 2.7 1013 90 32 0.01 563 552

FRI 06Z 20-DEC 7.1 4.6 1011 96 28 0.04 562 553

FRI 12Z 20-DEC 7.9 5.4 1010 99 56 0.13 560 552

FRI 18Z 20-DEC 7.3 5.6 1010 100 88 0.08 560 551

SAT 00Z 21-DEC 3.8 6.0 1011 99 36 0.06 560 551

SAT 06Z 21-DEC 2.2 3.4 1013 97 28 0.01 560 549

SAT 12Z 21-DEC 0.7 5.2 1016 94 53 0.00 561 549

SAT 18Z 21-DEC 3.5 7.4 1014 81 71 0.00 563 552

SUN 00Z 22-DEC 3.6 8.4 1009 98 99 0.43 564 557

SUN 06Z 22-DEC 2.6 7.9 1003 97 95 1.17 560 558

SUN 12Z 22-DEC 1.6 6.1 1003 97 99 0.61 557 555

SUN 18Z 22-DEC 1.8 6.3 1001 96 29 0.38 556 555

MON 00Z 23-DEC 0.4 -3.4 1010 94 69 0.04 549 542

MON 06Z 23-DEC -4.2 -8.6 1019 86 75 0.02 545 531

MON 12Z 23-DEC -11.3 -12.3 1026 79 5 0.00 540 520

MON 18Z 23-DEC -10.9 -13.4 1032 75 17 0.00 537 514

TUE 00Z 24-DEC -15.7 -13.1 1035 78 4 0.00 547 520

TUE 06Z 24-DEC -14.0 -8.1 1036 72 4 0.00 558 531

TUE 12Z 24-DEC -17.0 -5.1 1034 74 2 0.00 562 536

ECMWF Deterministic FORECAST FOR: ORD LAT= 41.98 LON= -87.90 ELE= 673

12Z DEC17

2 M 850 SFC SFC 700 6 HR 500 1000

TMP TMP PRS RHU RHU QPF HGT 500

(C) (C) (MB) (PCT) (PCT) (IN) (DM) THK

TUE 12Z 17-DEC -10.4 -5.5 1017 87 69 0.00 534 520

TUE 18Z 17-DEC -0.3 -8.1 1015 74 43 0.01 528 516

WED 00Z 18-DEC -3.0 -10.8 1017 71 34 0.00 536 523

WED 06Z 18-DEC -9.1 -9.0 1020 78 25 0.00 544 529

WED 12Z 18-DEC -13.3 -4.1 1023 81 70 0.00 551 533

WED 18Z 18-DEC -4.8 -0.3 1020 67 49 0.00 555 539

THU 00Z 19-DEC -1.7 2.1 1013 68 19 0.00 558 548

THU 06Z 19-DEC 1.2 5.9 1011 80 28 0.00 560 551

THU 12Z 19-DEC 1.2 4.0 1012 88 29 0.00 560 550

THU 18Z 19-DEC 3.7 2.3 1012 85 35 0.00 558 549

FRI 00Z 20-DEC 2.2 1.8 1011 96 60 0.00 557 548

FRI 06Z 20-DEC 2.8 2.3 1010 99 51 0.08 556 548

FRI 12Z 20-DEC 0.9 2.5 1012 96 43 0.06 555 546

FRI 18Z 20-DEC 0.9 1.1 1013 89 93 0.03 554 543

SAT 00Z 21-DEC 0.0 0.4 1012 91 50 0.02 553 543

SAT 06Z 21-DEC -0.8 -1.7 1012 95 53 0.01 552 542

SAT 12Z 21-DEC -2.1 -0.2 1015 92 49 0.00 553 542

SAT 18Z 21-DEC -1.0 1.1 1015 85 49 0.00 557 545

SUN 00Z 22-DEC -0.7 1.5 1012 94 99 0.06 557 548

SUN 06Z 22-DEC 0.4 0.6 1007 96 100 0.50 554 549

SUN 12Z 22-DEC 0.4 -2.6 1006 94 99 0.32 550 546

SUN 18Z 22-DEC 0.3 -4.4 1006 90 100 0.42 547 542

MON 00Z 23-DEC -3.6 -8.4 1013 85 97 0.14 542 531

MON 06Z 23-DEC -9.7 -11.0 1020 83 74 0.02 538 522

MON 12Z 23-DEC -15.6 -13.4 1026 83 11 0.00 533 513

MON 18Z 23-DEC -11.4 -15.2 1031 68 15 0.00 533 510

TUE 00Z 24-DEC -17.0 -13.8 1034 81 6 0.00 545 519

TUE 06Z 24-DEC -21.5 -9.8 1035 83 5 0.00 554 528

TUE 12Z 24-DEC -18.4 -6.7 1032 83 58 0.00 557 533

[toronto blizzard]

EURO text for the YYZ peeps.

 

SAT 00Z 21-DEC   0.5    -0.2    1013      91      98    0.04     551     541    
SAT 06Z 21-DEC  -0.5     1.6    1011      96      95    0.09     550     542    
SAT 12Z 21-DEC   0.3    -0.5    1011      94      60    0.07     549     540    
SAT 18Z 21-DEC   2.8    -2.3    1014      84      35    0.01     553     542    
SUN 00Z 22-DEC   0.7    -1.8    1017      93      29    0.00     557     544    
SUN 06Z 22-DEC   0.4     0.4    1012      96     100    0.13     557     548    
SUN 12Z 22-DEC   0.2     1.9    1005      96     100    0.92     556     552    
SUN 18Z 22-DEC  -1.7     1.7    1006      93      99    0.50     554     550    
MON 00Z 23-DEC  -3.2     3.0    1003      90      55    0.24     551     549    
MON 06Z 23-DEC  -5.3    -2.7    1006      86      66    0.06     545     540    
MON 12Z 23-DEC  -6.7    -8.3    1013      80      91    0.01     539     529

[A-L-E-K]

850s above 0 for a good portion of the liquid at ORD

[KokomoWX]

ECMWF Deterministic FORECAST FOR: DET LAT= 42.40 LON= -83.00 ELE= 627

12Z DEC17

2 M 850 SFC SFC 700 6 HR 500 1000

TMP TMP PRS RHU RHU QPF HGT 500

(C) (C) (MB) (PCT) (PCT) (IN) (DM) THK

TUE 12Z 17-DEC -10.1 -9.6 1016 87 27 0.00 531 518

TUE 18Z 17-DEC -3.5 -7.5 1014 77 100 0.00 528 517

WED 00Z 18-DEC -8.3 -9.1 1014 87 72 0.01 526 515

WED 06Z 18-DEC -10.1 -10.0 1016 92 28 0.00 532 519

WED 12Z 18-DEC -10.4 -12.0 1018 90 56 0.00 539 525

WED 18Z 18-DEC -2.7 -6.2 1020 69 35 0.00 547 531

THU 00Z 19-DEC -7.1 -1.0 1019 81 78 0.00 551 536

THU 06Z 19-DEC -7.2 -1.0 1015 76 41 0.00 555 543

THU 12Z 19-DEC -3.4 2.3 1014 81 20 0.00 557 546

THU 18Z 19-DEC 3.2 2.6 1014 81 39 0.00 558 546

FRI 00Z 20-DEC 2.0 1.6 1014 91 70 0.00 557 546

FRI 06Z 20-DEC 2.5 1.2 1012 92 88 0.03 556 547

FRI 12Z 20-DEC 3.3 3.1 1010 98 65 0.02 556 548

FRI 18Z 20-DEC 2.6 2.6 1011 97 86 0.05 554 545

SAT 00Z 21-DEC 0.7 2.6 1012 98 94 0.06 554 545

SAT 06Z 21-DEC 0.4 3.2 1010 96 59 0.10 554 546

SAT 12Z 21-DEC 1.1 0.0 1013 95 50 0.02 553 543

SAT 18Z 21-DEC 2.2 1.5 1015 89 34 0.00 558 546

SUN 00Z 22-DEC 0.9 3.8 1014 95 87 0.00 560 548

SUN 06Z 22-DEC 0.9 3.0 1007 97 100 0.54 559 553

SUN 12Z 22-DEC 1.2 3.0 1005 95 95 0.99 557 553

SUN 18Z 22-DEC 1.0 4.7 1002 95 72 0.61 555 553

MON 00Z 23-DEC -0.3 0.7 1003 91 40 0.04 550 548

MON 06Z 23-DEC -2.5 -6.7 1011 83 95 0.01 544 535

MON 12Z 23-DEC -10.0 -11.2 1019 86 67 0.00 538 523

MON 18Z 23-DEC -5.4 -14.9 1024 63 16 0.00 532 514

TUE 00Z 24-DEC -9.5 -16.6 1029 73 11 0.00 534 512

TUE 06Z 24-DEC -14.5 -12.8 1033 84 15 0.00 547 521

TUE 12Z 24-DEC -16.4 -10.4 1035 86 5 0.00 555 529

ECMWF Deterministic FORECAST FOR: IKK LAT= 41.07 LON= -87.83 ELE= 630

12Z DEC17

2 M 850 SFC SFC 700 6 HR 500 1000

TMP TMP PRS RHU RHU QPF HGT 500

(C) (C) (MB) (PCT) (PCT) (IN) (DM) THK

TUE 12Z 17-DEC -10.3 -5.3 1020 86 60 0.00 537 521

TUE 18Z 17-DEC -3.5 -7.3 1017 83 75 0.03 531 518

WED 00Z 18-DEC -2.9 -9.5 1019 71 47 0.00 538 523

WED 06Z 18-DEC -7.4 -7.1 1022 76 15 0.00 547 530

WED 12Z 18-DEC -12.3 -3.2 1024 80 62 0.00 553 535

WED 18Z 18-DEC -7.0 0.5 1022 78 42 0.00 558 541

THU 00Z 19-DEC -0.4 4.5 1014 67 25 0.00 561 550

THU 06Z 19-DEC 1.8 4.6 1013 78 17 0.00 562 552

THU 12Z 19-DEC 2.5 4.0 1013 86 15 0.00 562 552

THU 18Z 19-DEC 3.6 3.2 1013 91 29 0.00 561 551

FRI 00Z 20-DEC 4.2 2.6 1011 95 41 0.02 560 551

FRI 06Z 20-DEC 5.3 3.9 1010 97 29 0.05 560 551

FRI 12Z 20-DEC 4.7 3.9 1010 100 47 0.05 558 549

FRI 18Z 20-DEC 1.6 3.8 1012 96 87 0.05 557 547

SAT 00Z 21-DEC 0.7 3.5 1012 97 43 0.05 557 547

SAT 06Z 21-DEC 0.1 -0.3 1013 98 35 0.01 556 546

SAT 12Z 21-DEC -0.9 3.5 1015 95 40 0.00 557 545

SAT 18Z 21-DEC 0.1 5.3 1015 88 72 0.00 560 549

SUN 00Z 22-DEC 0.4 5.6 1010 98 100 0.25 560 552

SUN 06Z 22-DEC 1.0 4.5 1004 97 99 0.82 557 554

SUN 12Z 22-DEC 0.8 1.6 1004 97 100 0.42 554 550

SUN 18Z 22-DEC 0.6 -0.2 1004 95 91 0.30 551 548

MON 00Z 23-DEC -2.0 -6.7 1012 90 97 0.10 545 535

MON 06Z 23-DEC -7.3 -9.9 1020 82 53 0.02 541 526

MON 12Z 23-DEC -14.5 -12.1 1027 81 7 0.00 536 516

MON 18Z 23-DEC -13.9 -14.2 1032 78 21 0.00 535 511

TUE 00Z 24-DEC -20.2 -13.4 1035 81 5 0.00 547 521

TUE 06Z 24-DEC -23.8 -8.5 1036 84 4 0.00 556 530

TUE 12Z 24-DEC -16.7 -6.1 1033 77 28 0.00 560 535

[Chicago WX]

35-39 and rain. We're making progress.

 

EDIT: IKK takes the torch.

 

Thanks for the text data Jim.

[snowstormcanuck]

EURO text for the YYZ peeps.

 

SAT 00Z 21-DEC   0.5    -0.2    1013      91      98    0.04     551     541    

SAT 06Z 21-DEC  -0.5     1.6    1011      96      95    0.09     550     542    

SAT 12Z 21-DEC   0.3    -0.5    1011      94      60    0.07     549     540    

SAT 18Z 21-DEC   2.8    -2.3    1014      84      35    0.01     553     542    

SUN 00Z 22-DEC   0.7    -1.8    1017      93      29    0.00     557     544    

SUN 06Z 22-DEC   0.4     0.4    1012      96     100    0.13     557     548    

SUN 12Z 22-DEC   0.2     1.9    1005      96     100    0.92     556     552    

SUN 18Z 22-DEC  -1.7     1.7    1006      93      99    0.50     554     550    

MON 00Z 23-DEC  -3.2     3.0    1003      90      55    0.24     551     549    

MON 06Z 23-DEC  -5.3    -2.7    1006      86      66    0.06     545     540    

MON 12Z 23-DEC  -6.7    -8.3    1013      80      91    0.01     539     529

 

Thanks. Walking a very fine line.

 

I don't see how Snowstorms 3-5/ice/3-5 makes sense looking at this though. Temps at 850mb are well above freezing for the vast majority of this event.

[Chicago WX]

850s above 0 for a good portion of the liquid at ORD

 

lol, what? 

[Snowstorms]

Thanks. Walking a very fine line.

 

I don't see how Snowstorms 3-5/ice/3-5 makes sense looking at this though. Temps at 850mb are well above freezing for the vast majority of this event.

 

Well i had access to the maps not the text so I couldn't get a detailed analysis, only a broad one. 

 

By looking at that, it starts off as snow, but since temperatures are right at the freezing mark on the surface, this could be a major ice storm if it panned out. Its very similar to what the GGEM is painting. It ends off with some snow (1-3"). 

[harrisale]

EURO text for the YYZ peeps.

 

 

That's a lot of precip, over 2" QPF. Real mixed bag too. Comes in with about 3/4 inch of ice Sunday overnight, in line with the GFS and GGEM. Flash freeze of the rain beforehand plus ZR with a snow coating to finish it off? Now those are slippery conditions.

[toronto blizzard]

Thanks. Walking a very fine line.

 

I don't see how Snowstorms 3-5/ice/3-5 makes sense looking at this though. Temps at 850mb are well above freezing for the vast majority of this event.

Ya if anything it looks like a lot of IP/ZR to me.

[cmichweather]

850s above 0 for a good portion of the liquid at ORD

.56 of the liquid falls with 850s above 0 and of that .5 is falling with 850s at 0.6.

 

.9 falls after the 850s go below 0.

[Hoosier]

Euro text is better than looking at maps but we're still not seeing the entire column and I wonder if there are any warmer layers than 850 mb.

[A-L-E-K]

Euro text is better than looking at maps but we're still not seeing the entire column and I wonder if there are any warmer layers than 850 mb.

 

 

aren't there always

[csnavywx]

While strictly true, the strength of the WCB and the southern placement of the surface frontal boundary makes me think that the warm nose is likely above 850 at ORD. In that sense, 850s slightly above zero make for a lot more mixing than it would otherwise suggest.

 

Edit: Hoosier beat me to it.

[Hoosier]

aren't there always

 

 

Well, it can vary from setup to setup but not uncommon to see the max warm layer be at like 800-750 mb.

[Jonger]

I'm right on the line with this one.... 10 miles south could make a huge improvement.

 

At least the southern trails get hit in Michigan and Wisconsin.

[MidwestChaser]

I see the hand wringing brigade is doing what they do best. 

[Chicago WX]

Might be some overlapping of days, so it may be a moot point...but calendar day record highest precipitation for Indianapolis for both Saturday and Sunday.

 

Dec 21: 1.49" in 1918

Dec 22: 1.62" in 1981

 

And for the heck of it, highest calendar day for December all-time: 3.46" on December 3, 1873

[cyclone77]

This storm almost has the look of one of the rare ones that could deliver 1-2" of liquid followed by quite a dump on the back side with this double barrel structure of the surface lows.  If that ends up being the case this one will be very hard to pin down right to the end, as those systems always end up being very tricky.  Gonna be an interesting week to be sure.

[A-L-E-K]

This storm almost has the look of one of the rare ones that could deliver 1-2" of liquid followed by quite a dump on the back side with this double barrel structure of the surface lows.  If that ends up being the case this one will be very hard to pin down right to the end, as those systems always end up being very tricky.  Gonna be an interesting week to be sure.

 

 

those are the worst

[MadTown]

So being 4 days out and the rain/snow line marching north....thinking this trend will continue and that southern wisco is going to have mixing issues

[TimChgo9]

Okay, we are still a few days out, right now, models are depicting the  850's will be above zero, and surface  temps are marginal, at best.  Local forecasts are anywhere from 30 to 33 for Sunday. By late Sunday, 850's go below zero, and surface temps are about 30, perhaps.  This would give a flip flop between snow, and rain/snow mix. 

 

I am not buying, say, more than 4" out of this, if we do get snow.  Worst case, we have sleet, freezing rain, and some flurries blowing around after the precip passes east.

 

Still plenty of runs to go, but, the GFS has been more or less consistent with temps for the past few runs, so, in my mind, it's kind of hard to argue with it.