January 17th-18th Winter Storm Discussion

[kvegas-wx]

12z gfs looks like the changeover is slower and the precip quicker to move out.

Tw

 

This concerns me greatly.  I think the changeover will occur quickly but if this thing picks up speed the duration (or lack thereof) will kill our totals.  I think we are definitely well positioned here in the heart of the Triad.  Amazed at the rainfall over the last few days though.  Are you tracking totals here locally?  My gauge is shot and I had to take it down over Christmas.

[dsaur]

Here is where I'm confused.. If this low is suppose to explode with more moisture as the day goes on and it comes down heavy in places like Birmingham, I don't understand why the ATL area won't see the same.. weird.. What am I missing??

Warm air advection.  Most storms have a screw zone.  Warm air wrapping in, a dry slot, some other mechanism to disappoint some.  Ga. usually is in the screw zone to some extent, and here is another case.  The models yesterday were showing the snow coming out of Ala. shrinking off up to the north and skipping us, and that looks like it's coming to pass.  But ULL's are surprise storms so don't give up until the rain stops

  My attitude is I'm in a drought, so melty snow, or good wet rain....in a few hours it will all be liquid in the bottom of my bucket, so it's all good, and car top snow is no substitue for frozen sledding accumulation, so I take any positives I can, and go on to the next one

[I85Greenville]

GSP UPDATE: 

 

 

.NEAR TERM /THROUGH TONIGHT/...AS OF 1030 AM...A POTENT...COMPACT UPR LOW CAN BE SEEN ON WATERVAPOR OVR CENTRAL MS...MAKING EWD PROGRESS. THERE WAS STILL A STRONGDRY SLOT BETWEEN THE RATHER THIN WARM CONVEYOR BELT OVR GA AND ADEFORMATION ZONE OVR MS. SO OVERALL...QPF MAY NOT BE QUITE AS HIGHAS PREVIOUSLY EXPECTED. WITH THAT SAID...MODELS STILL IN GOODAGREEMENT ON STRONGEST LIFT AND HIGHEST RAIN RATES STILL TO COME FORTHE CWFA FROM MIDDAY THRU THE AFTN HOURS. THE CURRENT QPF AND FLOODWATCH/HYDRO CONCERNS STILL LOOK ON TRACK.THE BIGGER CONCERN IS ONCE THE LOW ARRIVES...HOW FAST WILL PRECIPTRANSITION FROM RAIN TO SNOW...AND WHERE WILL THE HEAVIEST SNOWACCUM BE. THE 12Z NAM LINES UP WITH THE HI-RES WRF AND OTHER HI-RESMODELS IN BRINGING THE DEFORMATION ZONE ACRS THE CWFA IN THE 21Z TO03Z TIME FRAME. THERE IS GOOD POTENTIAL FOR AN E-W BAND OF HEAVYPRECIP AS THE LOW PASSES BY. MODELS SEEM TO HAVE THE BAND TRACKROUGHLY ALONG I-85. THIS MAY MEAN LESS SNOW ACCUM IN THE MTNS...BUTA HIGHER POTENTIAL FOR A QUICK SHOT OF ACCUMULATING SNOW ACRS THEPIEDMONT. AS THE COLD AIR WILL FILTER IN FROM THE NE IN THELLVLS...THINK THE CHC OF ACCUM SNOW IS STILL BEST ACRS THE NCPIEDMONT...WITH LOWER PROB AS YOU HEAD SW TOWARD NE GA. WITH THATSAID...THERE IS ACCUMULATING SNOW ACRS MS UNDER THE LOW...WHICH WILLTRACK RIGHT THRU THE UPSTATE THIS EVENING. ALSO...THE NAM SHOWSSTRONG FRONTOGENESIS BAND LINING UP ALONG I-85 WITH NEG EPV IN THESTRONGEST OMEGA AND SNOW GROWTH ZONE IN THE MID LVLS. SO WHAT ITHINK WILL HAPPEN IS THAT AN INTENSE NARROW BAND OF PRECIP WILLACCOMPANY THE UPR LOW AS IT CROSSES THIS EVENING...AND THIS PRECIPMAY FALL MAINLY AS SNOW. HOWEVER...THIS WILL BE FAIRLYLOCALIZED...SO MUCH OF THE UPSTATE AND NE GA WILL PROBABLY ONLY SEEFLURRIES/DUSTING AT TAIL-END OF THE PRECIP LATE THIS EVENING. SO IHAVE OPTED TO EXPAND THE WINTER WX ADV TO INCLUDE THE I-85 CORRIDORFROM SPARTANBURG TO FRANKLIN GA TO MENTION POTENTIAL FOR SOME SNOWACCUM AND BLACK ICE. THIS WILL BE IN EFFECT FROM 6 PM TO 6 AMTONIGHT.OTHERWISE...ALL HAZARDS/PRODUCTS LOOK GOOD AND WERE LEFT AS IS.

[eyewall]

My final call:

[GreensboroWx]

12z gfs looks like the changeover is slower and the precip quicker to move out.

Tw

 

It looks the same as the previous runs to me.......

 

I would stick to the RAP forecasts for here on out anyway.

[Carvers Gap]

I'm generally on the same page as you but on the plus side the RAP is showing some rather good reflectivity for us for a decent period.  No clue what that translates into as far as accums, but bodes well for heavy snow falling.

Latest GFS run is still very decent, but the majority of any decent producing deformation bands for snow "seem" to be in NC now. The lesson from this is that the set-up we need does not work for central NC, and the same goes for central NC folks their set-up does not work for us. Basically, we wind up rooting against each other! Our best chances happen along arctic frontal boundaries that stall or a GOM low that rides throught the Piedmont. Cold air seems to get here too late....on recent GFS. Due to an almost complete absence of GOM lows we are in a huge snow drought.

[Lookout]

Right. That's kind of why I asked; they're generally overdone, and then you mentioned they might be underdone. Thanks for the reply!

 

I've never figured out how they "work". I mean that one time that's always stood out to me, it showed me getting 4 inches of snow, despite 925mb to surface temps being well above freezing and IIRC 850mb temps only being 0 to -1c. A 5 year old could tell you that wasn't going to happen. Then you have cases where he column is actually colder and more precip falls and it shows less (or sometimes even none) ...

[dsaur]

Btw, about that 7 to 10 inches i mentioned, I'm not saying it will happen, there is just a chance it will in a localized area. It might not be but a few tens of miles wide if it happens. I don't want folks to think I'm actually calling for that amount, just it's possible.

 

Could be one of those cases where 7 to 10 inches actually falls..but due to wet ground it won't accumulate to that much...much like that storm I had several years back..where I did have that much fall but had much less accumulation. I remember it making me sick LOL..and it also involved an upper low

Chris, I'm sure glad to see you posting.  You knowledge of the column for us Georgians is second to none.  It ain't a storm, even if a screw storm without your input   Meanwhile, if you're like me the drought hasn't ended yet, so all this rain is a boone, even if Carolina gets all the snow   And, who knows, the surprise may be on us for a change...and not the bad kind.  Get that back well, we've got sledding to do in Feb.   T

[burgertime]

GSP UPDATE: 

 

 

.NEAR TERM /THROUGH TONIGHT/...AS OF 1030 AM...A POTENT...COMPACT UPR LOW CAN BE SEEN ON WATERVAPOR OVR CENTRAL MS...MAKING EWD PROGRESS. THERE WAS STILL A STRONGDRY SLOT BETWEEN THE RATHER THIN WARM CONVEYOR BELT OVR GA AND ADEFORMATION ZONE OVR MS. SO OVERALL...QPF MAY NOT BE QUITE AS HIGHAS PREVIOUSLY EXPECTED. WITH THAT SAID...MODELS STILL IN GOODAGREEMENT ON STRONGEST LIFT AND HIGHEST RAIN RATES STILL TO COME FORTHE CWFA FROM MIDDAY THRU THE AFTN HOURS. THE CURRENT QPF AND FLOODWATCH/HYDRO CONCERNS STILL LOOK ON TRACK.THE BIGGER CONCERN IS ONCE THE LOW ARRIVES...HOW FAST WILL PRECIPTRANSITION FROM RAIN TO SNOW...AND WHERE WILL THE HEAVIEST SNOWACCUM BE. THE 12Z NAM LINES UP WITH THE HI-RES WRF AND OTHER HI-RESMODELS IN BRINGING THE DEFORMATION ZONE ACRS THE CWFA IN THE 21Z TO03Z TIME FRAME. THERE IS GOOD POTENTIAL FOR AN E-W BAND OF HEAVYPRECIP AS THE LOW PASSES BY. MODELS SEEM TO HAVE THE BAND TRACKROUGHLY ALONG I-85. THIS MAY MEAN LESS SNOW ACCUM IN THE MTNS...BUTA HIGHER POTENTIAL FOR A QUICK SHOT OF ACCUMULATING SNOW ACRS THEPIEDMONT. AS THE COLD AIR WILL FILTER IN FROM THE NE IN THELLVLS...THINK THE CHC OF ACCUM SNOW IS STILL BEST ACRS THE NCPIEDMONT...WITH LOWER PROB AS YOU HEAD SW TOWARD NE GA. WITH THATSAID...THERE IS ACCUMULATING SNOW ACRS MS UNDER THE LOW...WHICH WILLTRACK RIGHT THRU THE UPSTATE THIS EVENING. ALSO...THE NAM SHOWSSTRONG FRONTOGENESIS BAND LINING UP ALONG I-85 WITH NEG EPV IN THESTRONGEST OMEGA AND SNOW GROWTH ZONE IN THE MID LVLS. SO WHAT ITHINK WILL HAPPEN IS THAT AN INTENSE NARROW BAND OF PRECIP WILLACCOMPANY THE UPR LOW AS IT CROSSES THIS EVENING...AND THIS PRECIPMAY FALL MAINLY AS SNOW. HOWEVER...THIS WILL BE FAIRLYLOCALIZED...SO MUCH OF THE UPSTATE AND NE GA WILL PROBABLY ONLY SEEFLURRIES/DUSTING AT TAIL-END OF THE PRECIP LATE THIS EVENING. SO IHAVE OPTED TO EXPAND THE WINTER WX ADV TO INCLUDE THE I-85 CORRIDORFROM SPARTANBURG TO FRANKLIN GA TO MENTION POTENTIAL FOR SOME SNOWACCUM AND BLACK ICE. THIS WILL BE IN EFFECT FROM 6 PM TO 6 AMTONIGHT.OTHERWISE...ALL HAZARDS/PRODUCTS LOOK GOOD AND WERE LEFT AS IS.

 

Wow that's awesome news for MBY and points west of me. 

[beanskip]

15z RAP now has the 500 low CLOSED at 4z Friday morning -- that's the latest I've seen. It's about 100 miles east of Charlotte.

[chapelhillwx]

I've never figured out how they "work". I mean that one time that's always stood out to me, it showed me getting 4 inches of snow, despite 925mb to surface temps being well above freezing and IIRC 850mb temps only being 0 to -1c. A 5 year old could tell you that wasn't going to happen. Then you have cases where he column is actually colder and more precip falls and it shows less (or sometimes even none) ...

 

I guess treating the atmosphere as one-size-fits-all just doesn't work out most of the time. A broken clock is right twice a day though.

 

It'll be interesting to see what the liquid content of the snow is after the event is over.

[SBUWX23]

i dont see anything different with the GFS as well.

It looks the same as the previous runs to me.......

 

I would stick to the RAP forecasts for here on out anyway.

[griteater]

Here's the vertical velocities for Charlotte on the NAM (upward motion in negative values)...shows a burst of impressive values (-32+) in the 520 to 660mb range in the early evening with the deformation band.  2nd chart shows a coincident quick crash of the temperatures through the column...with saturation with respect to ice still present on RH profiles...all supports a burst of snow if the NAM is right.

 

Just looked at Greensboro, Asheville, and Raleigh profiles on the NAM...of these NC cities, the Charlotte and Raleigh profiles show the most impressive vertical velocity numbers.  Raleigh's has -32+ over a deeper layer...480-800mb.

[GvlleSC]

Upstate SC just issued for WWA until 6AM Friday morning.

[griteater]

Latest GFS run is still very decent, but the majority of any decent producing deformation bands for snow "seem" to be in NC now. The lesson from this is that the set-up we need does not work for central NC, and the same goes for central NC folks their set-up does not work for us. Basically, we wind up rooting against each other! Our best chances happen along arctic frontal boundaries that stall or a GOM low that rides throught the Piedmont. Cold air seems to get here too late....on recent GFS. Due to an almost complete absence of GOM lows we are in a huge snow drought.

 

Seems like to me that NE TN does well when the 850mb low tracks west of the mountains...but into a cold air mass...like 01/30/10

 

http://www.meteo.psu.edu/~fxg1/NARR/2010/us0130.php

[FallsLake]

^{One positive from RAHs late morning discussion:}

^{<last paragraph>}

^{OVERALL CONFIDENCE IS QUITE HIGH THAT WE`LL SEE BANDED PRECIP AS
THIS INTENSIFYING SYSTEM MOVES THROUGH THE REGION LATE AFTERNOON
THROUGH TONIGHT... HOWEVER MANY QUESTIONS REMAIN. HOW FAST THE COLD
AIR GETS IN HERE... WHERE THE PRECIP BAND WILL BE ORIENTED WHEN IT
ARRIVES... AND HOW LONG THE PRECIP WILL LAST BEFORE PULLING OUT ARE
CRUCIAL CONSIDERATIONS. OVER THE NEXT SEVERAL HOURS... WE WILL
FURTHER REFINE THE AMOUNTS AND TIMING... BASED ON OBSERVED TRENDS
AND THE NEWER MODEL RUNS. A QUICK LOOK AT THE NEWEST SREF ENSEMBLE
MEAN AND PROBABILITIES GENERALLY SUPPORTS THE CURRENT WARNING/
ADVISORY CONFIGURATION. -GIH}

 

[tnweathernut]

Wow that's awesome news for MBY and points west of me. 

Burger,  Hey man, appreciate all you do for this board with your pbp's.  If we are giving our snow up, I hope we can give it to you.  Looks like you will be very close, if not IN the best lift for this thing for a couple of hours.  Good luck.

[packfan98]

Do you mean East of Charlotte?  I might be looking at it wrong though.  It is still closed.  Looks to provide nice dynamics to the I-85 corridor.

15z RAP now has the 500 low CLOSED at 4z Friday morning -- that's the latest I've seen. It's about 100 miles west of Charlotte.

[Kilgore Trout]

Going to be interesting to see what happens in the mountains.  12Z RAP showing all liquid for AVL, while the NAM is outputting 2.6 inches of snow.  I know others are bullish on the mountains overperforming the models, so we will see what happens (fingers crossed).

[beanskip]

Yes typo -- my fault. 850 low also hangs together longer -- don't see it translate to higher precip rates or colder air -- maybe model will have to catch up at the surface.

Do you mean East of Charlotte?  I might be looking at it wrong though.  It is still closed.  Looks to provide nice dynamics to the I-85 corridor.

[burgertime]

Going to be interesting to see what happens in the mountains. 12Z RAP showing all liquid for AVL, while the NAM is outputting 2.6 inches of snow. I know others are bullish on the mountains overperforming the models, so we will see what happens (fingers crossed).

Not sure what you're talking about looked like when the heaviest moisture is moving in AVL is snow to me.

[HurricaneTracker]

Not sure what you're talking about looked like when the heaviest moisture is moving in AVL is snow to me. 

 

Agree.  RAP shows all snow after about 21Z, lasting up to 03Z.  Still a decent event here in the mountains.  I am sticking to my guns and going 5-8" average for Asheville.

[deltadog03]

RPM looks like its finally going to give NGA some love.

https://www.facebook.com/41FirstAlert

[BullCityWx]

RAP sounding for 0z tonight compared to the GFS and NAM:
 

Date: 9 hour  valid 0Z FRI 18 JAN 13Station: 35.33,-81.33Latitude:   35.33Longitude: -81.33-------------------------------------------------------------------------------LEV PRES  HGHT  TEMP  DEWP  RH  DD   WETB DIR SPD THETA THE-V THE-W THE-E   W     mb     m     C     C    %   C     C  deg knt   K     K     K     K    g/kg-------------------------------------------------------------------------------  0 1000    91                                                                 SFC  981   251   5.0   3.9  92  1.1   4.5  25  17 279.7 280.6 278.6 293.8  5.15  2  950   517   3.0   2.8  99  0.1   2.9  26  39 280.2 281.0 278.5 293.8  4.93  3  900   954   1.7   1.4  98  0.3   1.6  41  53 283.3 284.1 279.8 296.5  4.72  4  850  1413   0.3   0.1  99  0.2   0.2  49  48 286.4 287.2 281.0 299.3  4.53  5  800  1900   0.4   0.4 100  0.0   0.4  75  32 291.6 292.4 283.7 305.8  4.91  6  750  2418  -0.1  -0.1 100  0.0  -0.1 134  26 296.5 297.4 285.8 311.4  5.07  7  700  2969  -1.8  -1.8 100  0.0  -1.8 161  27 300.5 301.4 287.1 314.9  4.79  8  650  3557  -4.1  -4.3  99  0.1  -4.2 160  24 304.3 305.1 287.9 317.4  4.29  9  600  4186  -6.4  -6.7  98  0.2  -6.5 156  32 308.7 309.4 289.0 320.8  3.87 10  550  4862 -10.1 -10.3  98  0.2 -10.2 160  44 312.1 312.7 289.5 322.2  3.17 11  500  5590 -15.7 -16.2  96  0.4 -15.9 165  54 313.9 314.3 289.0 320.9  2.16 12  450  6373 -22.9 -23.4  95  0.5 -23.0 171  63 314.5 314.7 288.3 318.8  1.29 13  400  7224 -28.7 -35.8  50  7.1 -29.6 179  80 317.7 317.8 288.5 319.3  0.45 14  350  8172 -32.5                      186  99 324.9                         15  300  9244 -39.0 -64.0   5 25.0 -39.9 191 104 330.4 330.4 291.9 330.5  0.02 16  250 10470 -47.7                      198  94 335.1                         17  200 11909 -56.2                      199  99 343.7                         18  150 13741 -56.0                      224  83 373.6                         19  100 16265 -65.1                      228  65 401.9                        TRP                                             0                              WND                                             0                         

 

NAM:
 

Date: 12 hour Eta valid 0Z FRI 18 JAN 13Station: 35.33,-81.33Latitude:   35.33Longitude: -81.33-------------------------------------------------------------------------------LEV PRES  HGHT  TEMP  DEWP  RH  DD   WETB DIR SPD THETA THE-V THE-W THE-E   W     mb     m     C     C    %   C     C  deg knt   K     K     K     K    g/kg-------------------------------------------------------------------------------  0 1000   111                                                                 SFC  982   260   4.6   3.8  95  0.8   4.2  20  17 279.2 280.1 278.2 293.2  5.11  2  950   527   2.4   2.2  99  0.2   2.3  30  36 279.6 280.4 277.9 292.6  4.72  3  900   963   0.8   0.6  99  0.1   0.7  40  52 282.3 283.1 278.9 294.7  4.44  4  850  1422   0.4   0.3  99  0.1   0.3  49  45 286.5 287.3 281.1 299.6  4.59  5  800  1910   1.2   1.2 100  0.0   1.2  73  28 292.4 293.3 284.4 307.5  5.21  6  750  2428  -0.1  -0.1 100  0.0  -0.1 139  18 296.5 297.4 285.8 311.4  5.07  7  700  2979  -2.0  -2.0 100  0.0  -2.0 176  33 300.3 301.1 286.9 314.4  4.72  8  650  3567  -3.7  -3.7 100  0.0  -3.7 173  45 304.8 305.7 288.3 318.6  4.48  9  600  4196  -7.0  -7.0 100  0.0  -7.0 168  55 308.0 308.7 288.7 319.8  3.77 10  550  4870 -11.2 -11.7  96  0.5 -11.3 165  59 310.8 311.4 288.7 319.9  2.84 11  500  5594 -16.7 -18.2  88  1.5 -17.1 160  62 312.7 313.0 288.3 318.6  1.82 12  450  6378 -21.8 -28.7  54  6.9 -23.1 165  74 315.9 316.0 288.3 318.6  0.80 13  400  7236 -26.1 -45.7  14 19.6 -28.2 176  91 321.0 321.1 289.2 321.6  0.16 14  350  8191 -31.5 -55.9   7 24.4 -33.1 185 103 326.3 326.3 290.7 326.5  0.06 15  300  9265 -39.1 -62.5   7 23.4 -40.1 192 104 330.2 330.2 291.8 330.3  0.03 16  250 10491 -47.6 -71.4   5 23.7 -48.1 198  98 335.2 335.2 293.2 335.3  0.01 17  200 11933 -57.4 -74.5  10 17.1 -57.5 204  91 341.9 341.9 294.8 342.0  0.01 18  150 13747 -58.3 -72.0  16 13.7 -58.5 225  96 369.7 369.7 300.5 369.8  0.02 19  100 16262 -63.6 -83.0   5 19.5 -63.7 233  75 404.9 404.9 305.9 404.9  0.00TRP                                             0                              WND                                             0                              

 

GFS:
 

Date: 12 hour AVN valid 0Z FRI 18 JAN 13Station: 35.33,-81.33Latitude:   35.33Longitude: -81.33-------------------------------------------------------------------------------LEV PRES  HGHT  TEMP  DEWP  RH  DD   WETB DIR SPD THETA THE-V THE-W THE-E   W     mb     m     C     C    %   C     C  deg knt   K     K     K     K    g/kg-------------------------------------------------------------------------------  0 1000   109                                                                 SFC  980   270   4.3   3.3  93  1.1   3.8  17  17 279.1 279.9 277.9 292.6  4.93  2  950   526   2.8   1.4  91  1.4   2.1  24  36 280.0 280.7 277.8 292.3  4.45  3  900   963   1.7  -0.1  88  1.8   0.9  33  46 283.3 284.0 279.1 295.1  4.21  4  850  1424   1.1   0.7  97  0.4   1.0  40  39 287.3 288.2 281.7 300.8  4.74  5  800  1911   0.5   0.3  98  0.2   0.4  49  22 291.7 292.6 283.8 305.9  4.90  6  750  2428  -1.2  -1.4  98  0.2  -1.3  98   9 295.3 296.1 284.9 308.8  4.60  7  700  2977  -3.0  -3.4  97  0.4  -3.1 166  19 299.2 300.0 286.0 312.0  4.26  8  650  3562  -5.1  -5.6  96  0.5  -5.3 171  34 303.2 303.9 287.1 315.1  3.87  9  600  4188  -8.6  -9.0  97  0.4  -8.7 164  45 306.2 306.8 287.5 316.3  3.23 10  550  4857 -13.3 -14.2  93  0.8 -13.6 157  50 308.3 308.7 287.3 315.7  2.32 11  500  5575 -18.5 -22.5  71  4.0 -19.4 158  53 310.5 310.8 287.0 314.7  1.26 12  450  6354 -22.9 -33.0  39 10.0 -24.5 165  61 314.4 314.5 287.5 316.3  0.53 13  400  7210 -26.6 -40.0  27 13.4 -28.3 173  73 320.4 320.5 289.2 321.5  0.29 14  350  8164 -31.8 -50.2  14 18.4 -33.2 180  89 325.9 325.9 290.7 326.3  0.11 15  300  9238 -38.8 -58.4  11 19.6 -39.8 187  98 330.6 330.6 291.9 330.8  0.05 16  250 10465 -47.3 -62.3  16 15.0 -47.7 196  95 335.8 335.8 293.3 335.9  0.04 17  200 11911 -56.3 -67.4  24 11.1 -56.5 200  87 343.6 343.6 295.2 343.7  0.02 18  150 13733 -56.8 -70.1  17 13.4 -57.0 220  95 372.3 372.3 301.0 372.4  0.02 19  100 16267 -63.1 -80.2   8 17.1 -63.3 232  76 405.8 405.8 306.0 405.8  0.01TRP                                             0                              WND                                             0                              

 

 

 

 

 

[NavarreDon]

Looks like from what I can see things are shifting E of the central & southern mnts. & into the piedmont of NC. The n mnts & spots with higher elevation may do alright.

 

THE BIGGER CONCERN IS ONCE THE LOW ARRIVES...HOW FAST WILL PRECIPTRANSITION FROM RAIN TO SNOW...AND WHERE WILL THE HEAVIEST SNOWACCUM BE. THE 12Z NAM LINES UP WITH THE HI-RES WRF AND OTHER HI-RESMODELS IN BRINGING THE DEFORMATION ZONE ACRS THE CWFA IN THE 21Z TO03Z TIME FRAME. THERE IS GOOD POTENTIAL FOR AN E-W BAND OF HEAVYPRECIP AS THE LOW PASSES BY. MODELS SEEM TO HAVE THE BAND TRACKROUGHLY ALONG I-85. THIS MAY MEAN LESS SNOW ACCUM IN THE MTNS...BUTA HIGHER POTENTIAL FOR A QUICK SHOT OF ACCUMULATING SNOW ACRS THEPIEDMONT. AS THE COLD AIR WILL FILTER IN FROM THE NE IN THELLVLS...THINK THE CHC OF ACCUM SNOW IS STILL BEST ACRS THE NCPIEDMONT...WITH LOWER PROB AS YOU HEAD SW TOWARD NE GA. WITH THATSAID...THERE IS ACCUMULATING SNOW ACRS MS UNDER THE LOW...WHICH WILLTRACK RIGHT THRU THE UPSTATE THIS EVENING. ALSO...THE NAM SHOWSSTRONG FRONTOGENESIS BAND LINING UP ALONG I-85 WITH NEG EPV IN THESTRONGEST OMEGA AND SNOW GROWTH ZONE IN THE MID LVLS. SO WHAT ITHINK WILL HAPPEN IS THAT AN INTENSE NARROW BAND OF PRECIP WILLACCOMPANY THE UPR LOW AS IT CROSSES THIS EVENING...AND THIS PRECIPMAY FALL MAINLY AS SNOW. HOWEVER...THIS WILL BE FAIRLYLOCALIZED...SO MUCH OF THE UPSTATE AND NE GA WILL PROBABLY ONLY SEEFLURRIES/DUSTING AT TAIL-END OF THE PRECIP LATE THIS EVENING. SO IHAVE OPTED TO EXPAND THE WINTER WX ADV TO INCLUDE THE I-85 CORRIDORFROM SPARTANBURG TO FRANKLIN GA TO MENTION POTENTIAL FOR SOME SNOWACCUM AND BLACK ICE. THIS WILL BE IN EFFECT FROM 6 PM TO 6 AMTONIGHT.

[Carvers Gap]

Seems like to me that NE TN does well when the 850mb low tracks west of the mountains...but into a cold air mass...like 01/30/10

http://www.meteo.psu.edu/~fxg1/NARR/2010/us0130.php

When I was a kid folks basically said we wouldn't get snow unless it came up the valley...vernacular for what you just said. That is definitely one method. GOM lows into the Piedmont do work, but they are as rare as an ivory billed woodpecker these days. That was the money track until 93. Then, poof. Bowling ball lows, like today's, are tough to get snow here in NE TN unless the cold air mass is in place. The mountains and valley inhibit quick changeovers normally. Might be one of the toughest places of he planet to forecast.

[dwagner88]

Thundersleet being reported in southern middle TN now.

[Lookout]

Chris, I'm sure glad to see you posting.  You knowledge of the column for us Georgians is second to none.  It ain't a storm, even if a screw storm without your input   Meanwhile, if you're like me the drought hasn't ended yet, so all this rain is a boone, even if Carolina gets all the snow   And, who knows, the surprise may be on us for a change...and not the bad kind.  Get that back well, we've got sledding to do in Feb.   T

 

Thanks so much man. I really appreciate the kind words.

 

It's not just my back, sad to say. I Haven't posted much due to a variety of health issues plus there hasn't been anything to talk about until now (except football lol). But with the back issues, I can't stand to sit at the computer for very long..no matter how many  meds I take. In fact, I haven't been able to be close to comfortable no matter where I sit or lay down. It's been extremely painful and depressing. Only reason I'm able to be posting today is because of those shots but I don't know if they will work long term or it's a short term thing.

 

Anyway. about the rain...I've actually picked up 2.10 inches so far since yesterday. FFC's radar is really underestimating totals while robins is a little closer but still a good ways off (1 inch but 1.5 inches just to the sw) But  For example though, if you looked at the radar you would think it's just light/moderate rain but it's raining hard to very hard right now. I'm assuming it's forming at a lower level so radar isn't picking it up that well.

Actually standing water in the pasture

 

Not that anyone cares about rain right now in this thread lol

[MotoWeatherman]

15z RAP model pretty much leaves the ATL area with a cold rain.  Plus the composite reflectivity has everything pretty much north of the ATL.

[Kilgore Trout]

Not sure what you're talking about looked like when the heaviest moisture is moving in AVL is snow to me.

 

Used the model extraction tool from wxcaster.com.

 

 

 

Station ID: KAVL Lat:   35.43 Long:  -82.53 Elevation:   660.0                                                                                                                                                                                                  RAP Model Run: 12Z JAN 17, 2013                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 Forecast Hours:    0hr    1hr    2hr    3hr    4hr    5hr    6hr    7hr    8hr    9hr   10hr   11hr   12hr   13hr   14hr   15hr   16hr   17hr   18hr                                                                                                            Sfc Prs(mb):     934.6  936.5  936.8  936.6  935.2  935.2  935.2  934.9  934.3  933.0  933.0  933.1  934.4  936.0  937.5  939.9  941.8  942.8  943.3                                                                                                            Mean SLP (mb):  1010.9 1012.8 1013.2 1012.5 1011.2 1011.1 1011.1 1010.7 1009.9 1009.2 1009.6 1010.5 1012.5 1014.6 1016.4 1019.0 1020.9 1022.3 1023.0                                                                                                            2m agl Tmp (F):   46.6   47.3   47.3   47.3   47.2   46.2   44.7   42.5   41.4   41.8   40.9   39.7   37.3   34.5   35.0   34.7   35.0   34.4   32.9                                                                                                            2m AGL Dewpt(F):  44.7   44.7   45.4   46.1   46.6   45.5   43.3   40.7   39.5   39.3   39.2   38.2   36.1   34.0   33.0   32.9   32.0   30.3   28.3                                                                                                            2m agl RH (%):      93     91     93     96     97     97     95     93     93     91     93     94     95     98     92     93     89     85     83                                                                                                            10m agl W  Dir:    319    329    349    357    356    342    346    347      1      3    351    355    359    354    359    348    341    339    336                                                                                                            10m agl Spd(kt):     4      5      5      6      7     10     10     10     11      7      9     12     13     12     12      9      8     10     11                                                                                                            1hr Precip (in):  0.00   0.08   0.06   0.08   0.12   0.14   0.20   0.37   0.20   0.09   0.15   0.17   0.15   0.21   0.13   0.04   0.00   0.00   0.00                                                                                                            AccumPrecip(in):  0.00   0.08   0.14   0.22   0.34   0.48   0.68   1.05   1.25   1.34   1.49   1.65   1.80   2.01   2.14   2.18   2.18   2.18   2.18                                                                                                            1hr CnvPrp (in):  0.00   0.00   0.00   0.02   0.04   0.02   0.06   0.08   0.03   0.02   0.02   0.00   0.00   0.00   0.00   0.00   0.00   0.00   0.00                                                                                                            Precip H20 (in):   1.2    1.1    1.1    1.1    1.1    1.1    1.1    1.0    1.0    0.9    0.9    0.8    0.7    0.6    0.6    0.5    0.3    0.2    0.2                                                                                                            Lifted Index©:  11.8   11.7   10.6    9.7    9.4   10.1   13.1   14.8   14.8   14.0   14.9   16.0   14.8   14.0   11.7   14.1   15.6   17.0   18.9                                                                                                            Sfc CAPE (J/kg):   0.0    0.0    0.0    0.0    0.1    2.4    3.6    6.9    4.3    2.4    0.0    0.0    0.0    0.0    0.0    8.7    8.6    0.0    0.0                                                                                                            Sfc CINH (J/kg):  -1.4    0.5   -0.3    1.2    0.4    0.1    0.3    0.2    0.1   -1.3   -0.7   -0.2    0.8    0.6   -0.5    0.2   -0.4    0.0    0.3                                                                                                            0-3km SRH(J/kg): 186.7  208.2  260.1  381.0  530.2  686.8  721.6  589.7  458.5  423.6  424.2  397.4  347.4  214.5  -95.7 -171.3   45.8 -107.4 -129.8                                                                                                            700mb VV(-ub/s):   4.6   10.6    6.4    6.5   14.1   25.1   25.7   22.0    5.6   19.6   22.0   21.8   19.1   14.1    4.3   -7.4   -3.2  -12.0   -9.8                                                                                                            Thk1000-500mb(m)5610.8 5607.7 5600.2 5598.1 5598.9 5593.3 5582.5 5569.1 5558.6 5551.0 5533.0 5505.0 5461.1 5426.0 5418.4 5424.4 5421.8 5425.8 5432.6                                                                                                            Thk1000-850mb(m)1366.2 1365.9 1364.9 1364.1 1361.4 1358.5 1353.4 1351.7 1348.9 1346.4 1343.1 1335.3 1327.7 1321.4 1319.1 1318.8 1318.2 1317.2 1317.4                                                                                                            Thk850-700mb(m):1593.2 1593.3 1594.6 1594.3 1593.3 1590.7 1584.7 1573.6 1571.9 1568.3 1560.7 1553.7 1545.5 1537.1 1533.5 1531.7 1531.2 1535.3 1537.3                                                                                                            Heat Index (F):     47     47     47     47     47     46     45     42     41     42     41     40     37     35     35     35     35     34     33                                                                                                            PType:                 LIQUID LIQUID LIQUID LIQUID LIQUID LIQUID LIQUID LIQUID LIQUID LIQUID LIQUID LIQUID LIQUID LIQUID LIQUID