January Pattern and Storm Discussion II

[Bevo]

Temps from the BL to 850 just do not look conducive to snow outside WNC elevations.  In my opinion, delta has the pulse of this one correct.

[CandymanColumbusGA]

Burger, and others, it looks too warm at all levels *from the BL to 850*  I say this is an ALL rain event E of the MS river

Yeah... I'm already saying we're looking at a cold rain Thursday night over in Columbus on Facebook.. Don't want everyone seeing the snow maps and being like YAY!!!!!!!!!!!!!!!..... NO! Unless we get some dry air in the lower levels to help with Evap cooling, this will be a bigger rain event than snow event. At least for you and me and most in Alabama and Georgia, outside of the mountains. But, we'll be ever vigilant for any changes...

[deltadog03]

I'd say the upstate of SC too. 

 

The sounding data for GSO looks very favorable for snow at this point!  Not sure about amounts yet, though.

After looking at it again, yes, they could get VERY close as well.  I would say GSP and NE

[burgertime]

Everyone new to this should also remember not to hug one solution. We're gonna see this low going all over the map more than likely in the upcoming days with models varying. 

[Shawn]

Looking at soundings for various cities shows that these snow maps are incorrect.  I don't understand what they're doing.  There aren't just surface temp problems, but upper level temp issues as well.

[CADManager]

Completely disagree with Brad there.  Temps in the mid to upper 30's and 850's that are above 0c are not going to get 1-2" of snow on the ground.  Now, there is a little bit of room for some dynamic and evap cooling, but its not much, and will be HIGHLY localized

I think what Brad was posting is what the GFS showed, not his opinion on snow depth. I've seen some pretty strong dynamic cooling as some of these systems pass through N. Ga, possibly helped by the "in situ" CAD that somtimes occurs.

[Snowless in Carrollton]

Its going to be a close call for snow/rain Thursday nights. Many factors come into play including strength of low, track, and BL conditions. Upper levels are looking good but the BL may be an issue.

 

Arctic blast ready to invade after the low exits.

Is the time of day a factor as well ? I would think a night time or early morning event would help with accumulations compared to a late morning or afternoon event.

[deltadog03]

There is a little wiggle room in the lowest levels to potentially pop someone, **IF** the right conditions present themselves.  So, its certainly possible, but highly unlikely.  Thats why I am not a super fan of the snowfall maps.  

[strongwxnc]

Sitting an hour nne of GSP,, I like KFQD sounding at day 4

 

Date: 4 day AVN valid 12Z FRI 18 JAN 13Station: KFQDLatitude:   35.43Longitude: -81.94-------------------------------------------------------------------------------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   220                                                                 SFC  973   441   1.7   0.0  89  1.7   1.0  22   7 277.0 277.7 275.5 287.8  3.93  2  950   635   2.0  -2.8  70  4.8   0.0  35  16 279.2 279.7 275.7 288.3  3.26  3  900  1069  -0.8  -4.0  78  3.3  -2.0  42  18 280.7 281.3 276.5 289.6  3.14  4  850  1525  -1.1  -4.7  76  3.6  -2.6  49  16 285.0 285.5 278.6 294.0  3.16  5  800  2009  -0.8  -4.1  78  3.3  -2.1  56  11 290.3 291.0 281.6 300.6  3.53  6  750  2525  -1.4  -3.4  86  2.0  -2.3  54   5 295.1 295.8 284.1 306.8  3.97  7  700  3073  -3.0  -4.5  89  1.5  -3.7  47   3 299.2 299.9 285.7 310.9  3.91  8  650  3658  -5.6  -7.2  89  1.6  -6.2  59   5 302.6 303.3 286.5 313.2  3.43  9  600  4282  -8.3 -11.9  75  3.7  -9.6  47   9 306.6 307.0 286.9 314.6  2.55 10  550  4954 -11.4 -16.9  64  5.5 -13.1   1   9 310.6 310.9 287.6 316.6  1.85 11  500  5678 -16.7 -20.2  74  3.5 -17.6 298  10 312.7 313.0 288.0 317.8  1.54 12  450  6459 -23.7 -24.4  94  0.7 -23.8 221  13 313.5 313.7 287.9 317.5  1.18 13  400  7307 -30.6 -31.0  96  0.4 -30.6 212  12 315.3 315.4 288.0 317.8  0.72 14  350  8245 -35.3 -42.7  47  7.4 -36.0 320  19 321.1 321.2 289.4 322.1  0.25 15  300  9310 -39.9 -60.1  10 20.3 -40.7 299  24 329.2 329.2 291.5 329.4  0.04 16  250 10533 -48.5 -64.3  14 15.8 -48.9 269  40 333.9 333.9 292.8 334.0  0.03 17  200 11967 -57.7 -67.5  28  9.8 -57.8 261  50 341.4 341.4 294.7 341.5  0.02 18  150 13758 -62.8 -70.1  37  7.3 -62.9 252  65 361.9 361.9 299.1 362.0  0.02 19  100 16231 -65.6 -76.5  20 10.9 -65.7 259  60 401.1 401.1 305.3 401.1  0.01

 

 

After looking at it again, yes, they could get VERY close as well.  I would say GSP and NE

[GreensboroWx]

Yeah, this isn't the "big one" by any means....just the first close call of the season. Hopefully, once the cold air/PV starts to have more influence we can get a Gulf storm to generate and everybody can get in on the fun.

[MichaelJ]

http://www.twisterdata.com/index.php?sounding.lat=33.7243&sounding.lon=-84.4189&prog=forecast&model=GFS&grid=3&model_yyyy=2013&model_mm=01&model_dd=14&model_init_hh=12&fhour=84&parameter=TMPF&level=2&unit=M_ABOVE_GROUND&maximize=n&mode=singlemap&sounding=n&output=image&view=large&archive=false&sounding=y&sndclick=y

 

Thats 00z Friday for ATL *or near there*

Classic warm nose signature there

[DaculaWeather]

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE NASHVILLE TN
1044 AM CST MON JAN 14 2013

...A LIGHT WINTRY MIX WILL BE POSSIBLE THIS EVENING...

.A PLUME OF MOISTURE FROM THE GULF OF MEXICO WILL STREAM INTO
THE MID STATE LATER THIS AFTERNOON AND THROUGH THE OVERNIGHT
HOURS. WITH SUB-FREEZING TEMPERATURES EXPECTED LATER TONIGHT...A
LIGHT WINTRY MIX OF SNOW...FREEZING RAIN AND A COLD RAIN WILL BE
POSSIBLE THROUGH EARLY TUESDAY MORNING ACROSS THE WESTERN TWO
THIRDS OF MIDDLE TENNESSEE.

[ncwinterwxman]

Yea...the algorithms that output those snowfall total maps are based on a ton of if, then statements...and given the cold bias nature of the gfs, you have to be leary of saying much about any kind of accumulations right now outside of the higher elevations...

There is a little wiggle room in the lowest levels to potentially pop someone, **IF** the right conditions present themselves.  So, its certainly possible, but highly unlikely.  Thats why I am not a super fan of the snowfall maps.  

[MotoWeatherman]

It's gonna stink to watch a cold rain here in N GA with BL issues.  Perhaps Big Canoe and other elevations above 2,500 feet in GA can eek some snow out of this.

[GreensboroWx]

It will be fun to track the different models during the week since VERY SMALL differences will result in huge consequences across the SE. 

 

Honestly, I'm more interested on the cold air afterwards. 

[FallsLake]

It will be fun to track the different models during the week since VERY SMALL differences will result in huge consequences across the SE. 

 

Honestly, I'm more interested on the cold air afterwards. 

I'm still hopeing for the day 8 period. Nothing showing but it looks like something could brew.

 

Just for fun: 12 GFS at 288:

 

[packbacker]

We are in the Euro's sweetspot now, lets see if stays with the 0z run or not.

[MotoWeatherman]

Any chance a little bit of snow mixes in for Atlanta ? I haven't even seen a snowflake in 2 years. Just seeing a couple flakes fall would make my winter.

 

I would personally be surprised if ATL saw anything but rain.

[burrel2]

12z CMC...

 

It's hard to tell what the thicknesses are these maps, but I do like the placement of low pressure and the high pressure in new england.

 

 

Thoughts?

[MotoWeatherman]

12z CMC...

 

It's hard to tell what the thicknesses are these maps, but I do like the placement of low pressure and the high pressure in new england.

 

 

Thoughts?

 

Those look like perfect placement for areas in NE GA to upstate of SC to the WNC mountains.  Of course that's without any idea of BL temps and 850's per this model run.  But on the BW maps it looks great.

[tazaroo]

GFS 12z Ensemble mean is more North with the precip but also looks warmer.

[beanskip]

Wow -- CMC a total gully washer/dumping -- widespread 1+ inch QPF.

 

[beanskip]

Need that high to hang in there a little longer though ....

Wow -- CMC a total gully washer/dumping -- widespread 1+ inch QPF.

[MotoWeatherman]

Wow -- CMC a total gully washer/dumping -- widespread 1+ inch QPF.

And the depiction of the 700mb low near Atlanta.  That type of track would bode well for the mountains of GA, WNC, east TN and the upstate of SC.

[DaculaWeather]

Not sure the best place for this. I'm capturing the temp contour images for 00Z and 12Z and creating loops. You can watch as time goes on and see the evolution of the cold each day at the same time. I think it will be kinda cool as the cold air gets closer this way. Right now it only started on Wednesday of last week.

 

http://www.daculaweather.com/4_00_temp_loop.php

http://www.daculaweather.com/4_12_temp_loop.php

 

Each day I'll add more images and keep building this. 

[deltadog03]

I think what Brad was posting is what the GFS showed, not his opinion on snow depth. I've seen some pretty strong dynamic cooling as some of these systems pass through N. Ga, possibly helped by the "in situ" CAD that somtimes occurs.

agreed!  I should have said of the solution that was posted....I figured that is not his opinion.

[packbacker]

GFS 12z Ensemble mean is more North with the precip but also looks warmer.

 

Well one reason is the GEFS is slower than the OP, by a good 6 hours.  That's been a trend by all models this morning, slower system, could be mean warmer system as the PV lifts out, that would essentially guarantee an all rain event.

 

That would allow this system to move north more, maybe the MA would get the storm than.

[DaculaWeather]

Updated 

 

 

EXTENDED FORECAST DISCUSSIONNWS HYDROMETEOROLOGICAL PREDICTION CENTER COLLEGE PARK MD1020 AM EST MON JAN 14 2013VALID 12Z THU JAN 17 2013 - 12Z MON JAN 21 2013USED THE 00Z/14 ECMWF FOR THE FRONTS AND PRESSURES FOR DAYS 3THROUGH 5, THEN SWITCHED TO THE 00Z/14 ECENS MEAN DAYS 6 AND 7 TOMITIGATE THE SYNOPTIC DETAIL UNCERTAINTY INHERENT TO THAT TIMERANGE. THE 00Z/14 GFS--UPON WHICH THE LATEST MOS IS BASED--WAS ADEVELOPED OUTLIER WITH THE WAVE CROSSING THE GREAT LAKES DURINGTHE PERIOD. THE GEM GLOBAL AND UKMET HAVE HAD A STRING OF VOLATILESOLUTIONS. THE DETERMINISTIC ECMWF, WHILE NOT STABLE EITHER, HASBEEN USABLE WHEN IT HAS JIBED WITH ITS ATTENDANT MEAN--AS IS THECURRENT CASE. THE PATTERN IS A DRY ONE AS A WHOLE FOR THE NATION,WITH A RIDGE OVER THE WEST AND CONTINENTAL POLAR AND ARCTIC AIRPOURING INTO THE CENTRAL AND EAST. WHILE THE SOUTHEAST RIDGE ISSTILL IN PLACE, A COUPLE MORE WAVES MAY BE FORCED FAR ENOUGHNORTHWARD TO PRODUCED STRIPES OF LIGHT PRECIPITATION FROM THETENNESSEE VALLEY EASTWARD TO THE MID ATLANTIC AND CAROLINA COASTS.IN TERMS OF THE ARCTIC AIR, THE MODELS HAVE BEEN ADVERTISING ANEVENTUAL TRANSPORT OF THE SUPERFRIGID AIR OVER CANADA IN THENORTHERN TIER OF STATES FOR SOME TIME NOW--USUALLY AT THE END OFTHE MEDIUM RANGE OR BEYOND. THE BACKING OFF OF THIS PREDICTEDTRANSPORT HAS NOT BEEN VERY PREPOSSESSING IN TERMS OF CONFIDENCEIN THE EVENT. STILL, FEEL THERE IS CURRENTLY ENOUGH CRITICAL MASSIN THE GUIDANCE TO INTRODUCE SIGNIFICANT NEGATIVE TEMPERATUREANOMALIES OVER THE NORTH CENTRAL STATES DAYS 6 AND 7 IN THISFORECAST PACKAGE.CISCO

 

[jshetley]

STRONGLY agree...outside of a few inches in the mountains, this will likely be a non-event IMO...that's why I haven't really said anything about it...

 

Regarding the cold shot this weekend into next week, it is looking more and more like a transient shot of cold air before a more sustained period of cold comes in by early February...

This sounds about right since I'm thinking this winter may turn out a lot like the 1988-1989 winter that gave much of our area a major icestorm around the 17 of Feb that year and a snow event a week later.

[deltadog03]

12z CMC is too warm for EVERYONE except the mtns, and maybe CLT to RDU.....850's barely dip into NC *which would includes the areas mentioned*