1/17/16 Winter Weather Threat

[BornAgain13]

I dont like the NAM anymore lol

[franklin NCwx]

Maps?

http://mageval.ncep.noaa.gov/ImageFourPanel.php?image=data%2Fgfs%2F12%2Fgfs_namer_048_200_wnd_ht%7C500_vort_ht%7C1000_500_thick%7C850_temp_ht_s.gif&model=gfs&area=namer&cycle=12&param=200_wnd_ht%7C500_vort_ht%7C1000_500_thick%7C850_temp_ht&fhr=048&group=Model+Guidance&preselected_formatted_cycle_date=20160115+12+UTC&ps=area&use_mins=no&scrollx=90&scrolly=0

[Met1985]

Seems to me all the "all hail king EURO" should be "all hail king GFS". LOL. Everyone else trended to the GFS...more or less.

Exactly. I was just thinking I jumped to early. The gfs has done a lot better than the euro.

[PackGrad05]

RAH taking their time again with the AFD

[Shawn]

KCAE says:

 

 

ALTHOUGH THE TRACK OF THE LOW WILL BE SOUTH OF THE AREA  
MOISTURE THROUGH THE SNOW GROWTH REGION IS LIMITED TO A SHORT  
TIME FRAME AROUND SUNRISE...HOWEVER DURING THIS TIME THERE IS A  
SIGNIFICANT WARM NOSE FROM THE SURFACE TO 6 KFT WHICH WILL BE MORE  
THAN ENOUGH TO MELT ANY SNOW AND ENSURE ALL PRECIP IS RAIN.

[DaculaWeather]

Matt Grantham's AFD from Birmingham

--------------------

A PARTIAL PHASE OF THE SHORTWAVES IS NOW INDICATED BY ALL
OPERATIONAL MODELS...AND MORE PHASING REMAINS POSSIBLE. WITH THE
WAY THIS SYSTEM HAS TRENDED OVER THE LAST 24-48 HOURS...WE HAVE
TO REMAIN OPEN TO THE POSSIBILITY OF A MUCH STRONGER SURFACE LOW
AND MORE WELL-DEVELOPED PRECIP SHIELD ACROSS THE INLAND DEEP
SOUTH. YESTERDAY'S NORTHERN OUTLIERS OF THE ECMWF ENSEMBLE MEMBERS
ARE NOW SIMILAR TO THE SOLUTION OF THE OPERATIONAL MODEL. NOW
THESE NORTHERN OUTLIERS ARE EVEN FARTHER NORTH AND DEEPER WITH
SOME MEMBERS DOWN TO 989 MB IN THE EXTREME NORTHERN GULF OF
MEXICO. WHILE IT DOES NOT SEEM LIKELY THAT THESE SOLUTIONS WOULD
VERIFY...THERE IS A NON-ZERO CHANCE THEY MIGHT. ACCORDINGLY WITH
THE NORTHWARD SHIFT IN MODELS...POPS HAVE BEEN RAISED
SUBSTANTIALLY FOR 06-12Z SUNDAY WITH QPF AMOUNTS RANGING FROM
0.01-0.20 INCH FROM NORTHWEST TO SOUTHEAST. THIS SITUATION WILL
HAVE TO BE MONITORED CLOSELY DUE TO THE POTENTIAL FOR DYNAMIC AND
DIABATIC COOLING IN THE EVENT THAT HEAVIER THAN FORECAST PRECIP
FALLS ALONG AND NORTH OF I-20...WHERE THERMAL PROFILES WOULD
SUPPORT RAIN CHANGING TO SNOW...BUT NO ACCUMULATIONS HAVE BEEN
INCLUDED IN THIS UPDATE. THIS IS AN UNUSUAL SITUATION TO BE IN
LESS THAN 48 HOURS OUT...AND ANOTHER SET OF MODEL RUNS IS NEEDED
TO REMOVE THE UNCERTAINTY.

[dsaur]

I won't throw out the Nam, as that little dangle in Ga. drops the cold over my house, finally, when all the rest stop at I 20...at least the Nam seems to know the earth doesn't end there, lol.

  I'm holding out for what I call the Guy Sharpe effect.  Back in the late 70's/early 80's a low was in the gulf and all the mets said it would be a 35/37 cold rain....especially the Gray Ghost..but after living thru Jan 73, and others, I knew better than to dismiss a winter gom low out of hand...and it was heavy rain, until around 4 am, when the rain started to bounce, and got much louder.  One of my favorite storms. An inch or two of rain, followed by over 3 inches of sleet   Whenever a low is in the gulf in winter, I hold out for the Guy Sharpe effect, and it's happened more than once, to folks who follow models too ridgedly    It's the weather...anything can happen, and sometimes does! Tony

[Jon]

Little differences between 18z and 12z GFS...basically a carbon copy through 48***

 

18z GFS a tad slower with the low at 57 hrs, although not much. Next.

[MillerA]

GSP Disco

Short term /Saturday night through Monday/...

as of 2 PM Friday...the atmosphere will begin to moisten from the

top-down once again on Sat night...as the next...more potent

southern stream short wave trough moves rapidly across the southeast

Continental U.S.. while the bulk of the positive DPVA will pass south of the

western Carolinas and northeast Georgia...short term guidance continues

to depict a deformation zone becoming established across the

southern Appalachians and surrounding areas...near the entrance

region of 150kt upper jet. Model cross-sections within this

deformation axis continue to appear rather intriguing...with

near-saturated air extending well into the dendritic ice Crystal

growth region. In that sense...it is not surprising that

deterministic guidance has trended a bit wetter...with consensus quantitative precipitation forecast

of .05-.1 inch indicated across much of the forecast area between

06z and 18z Sunday. This is also in line with the latest ensemble

output.

Probability of precipitation have been increased to a solid chance across the mountains during

this time frame...while 30 probability of precipitation will be retained across the Piedmont

and foothills. In terms of p-type...this continues to look strictly

like a rain/snow issue. A consensus of operational model thickness

forecasts and ensemble p-type probabilities lends little support to snow

possibilities along and south of the I-85 corridor...and the rain

/snow line has been shifted a bit north. Meanwhile...all-snow

appears to be a good bet across the mountains...with a rain/snow mix along

the I-40 corridor east of the mountains the mountains could see anywhere from

a dusting to an inch of snowfall...with perhaps up to a half inch

across the northern NC foothills...but confidence in measurable

snowfall is still rather low...especially outside the mountains

[griteater]

18z RGEM is stray flurries

 

[GlaringSun]

Looks like my area has barely a chance for snow now..

[Bsudweather]

18z not much different than 12z. Here in my area north of I85 in Upper pickens looks a tad colder 2m mid 30s with 850s around -3. So I could still see the higher upstate folks seeing snow or rn/sn mix just not much in way of accumulations.

[BIG FROSTY]

18z RGEM is stray flurries

That's not good!

[LithiaWx]

Looks like my area has barely a chance for snow now..

We will probably get some snow. Accumulations are near 0 percent chance.

[packfan98]

Happy Hour sure didn't live up to its name! Nam/gfs/RGEM. Wow! I haven't checked these in great detail, but these 18z runs seem to be the first suite to slow down the energy. The prior few runs were speeding them up and getting a little more phasing. I guess the 0z will be telling!

[Snowless in Carrollton]

Looks like my area has barely a chance for snow now..

if we get a flurry consider it a victory. Its one of those kind of winters.

[SnowNiner]

GSP Disco

Short term /Saturday night through Monday/...

as of 2 PM Friday...the atmosphere will begin to moisten from the

top-down once again on Sat night...as the next...more potent

southern stream short wave trough moves rapidly across the southeast

Continental U.S.. while the bulk of the positive DPVA will pass south of the

western Carolinas and northeast Georgia...short term guidance continues

to depict a deformation zone becoming established across the

southern Appalachians and surrounding areas...near the entrance

region of 150kt upper jet. Model cross-sections within this

deformation axis continue to appear rather intriguing...with

near-saturated air extending well into the dendritic ice Crystal

growth region. In that sense...it is not surprising that

deterministic guidance has trended a bit wetter...with consensus quantitative precipitation forecast

of .05-.1 inch indicated across much of the forecast area between

06z and 18z Sunday. This is also in line with the latest ensemble

output.

Probability of precipitation have been increased to a solid chance across the mountains during

this time frame...while 30 probability of precipitation will be retained across the Piedmont

and foothills. In terms of p-type...this continues to look strictly

like a rain/snow issue. A consensus of operational model thickness

forecasts and ensemble p-type probabilities lends little support to snow

possibilities along and south of the I-85 corridor...and the rain

/snow line has been shifted a bit north. Meanwhile...all-snow

appears to be a good bet across the mountains...with a rain/snow mix along

the I-40 corridor east of the mountains the mountains could see anywhere from

a dusting to an inch of snowfall...with perhaps up to a half inch

across the northern NC foothills...but confidence in measurable

snowfall is still rather low...especially outside the mountains

Yes! The shut out continues. We're number one, history in the making clt!

[Solak]

RAH posted a late afternoon update...

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/... AS OF 430 PM FRIDAY...A COLD FRONT NOW OVER THE UPPER MIDWEST WILL SETTLE SOUTHEAST ANDACROSS CENTRAL NC SATURDAY NIGHT...WITH ONLY MARGINALLY COLD AND DRYAIR...CHARACTERIZED BY BOTH SFC TEMPERATURES AND DEWPOINTS IN THE30S...LIKELY TO BE IN PLACE BY THE TIME LIGHT PRECIPITATION ARRIVESSUNDAY MORNING. THIS WILL LARGELY BE A RESULT OF A POORLY-PLACEDCOLD/ARCTIC SURFACE HIGH OVER THE PLAINS STATES - WELL TO THE NORTHAND WEST OF WHAT IS CONSIDERED TO BE A FAVORABLE POSITION FOR WINTRYWEATHER IN CENTRAL NC. WHILE THE MODELS HAVE SHIFTED NORTHWARD WITH THE LOW TRACK FROM THEGULF OF MEXICO TO OFFSHORE THE SOUTHEAST US COAST...AND WITH THEASSOCIATED PRECIPITATION SHIELD ALONG THE NORTHERN PERIPHERY OF THELOW TRACK...THIS SHIELD SHOULD STILL PROVE RELATIVELYINCONSEQUENTIAL FOR MOST OF CENTRAL NC...PARTICULARLY IN TERMS OFANY POSSIBILITY OF LIGHT SNOW. IE. EVEN IF IT WERE TO BULGENORTHWARD INTO THE SANDHILLS AND SOUTHERN-CENTRAL COASTALPLAIN...BOUNDARY LAYER TEMPERATURES THERE WILL SIMPLY BE TOO MILD TOSUPPORT ANYTHING BUT RAIN. MEANWHILE ACROSS THE PIEDMONT...WE STILL ANTICIPATE A LIGHTER AREAOF PRECIPITATION TO ACCOMPANY THE APPROACH-PASSAGE OF A PAIR OFPARTIALLY-PHASED SHORTWAVE TROUGHS...WHOSE LOW LEVEL MASS FIELDRESPONSE WILL PROMOTE A BRIEF PERIOD OF MOISTURE CONVERGENCEALONG...AND ISENTROPIC UPGLIDE ATOP...THE WEAK SURFACE COLD FRONTFORECAST TO SETTLE INTO CENTRAL-SOUTHERN NC BY SUNDAY MORNING.HERE...QPF HAS ALSO INCREASED SLIGHTLY SINCE FORECAST GUIDANCE FROMYESTERDAY...BUT STILL LIGHT AT LESS THAN A TENTH OF AN INCH. EVENHERE...THE BOUNDARY LAYER WILL STILL BE ONLY MARGINALLY SUPPORTIVEOF SNOW...WITH COOLING VIA SUBLIMATIONAL COOLING/WET-BULBING...ANDTHEN MELTING OUT...OF A NEAR SURFACE AROUND FREEZING LAYER. AS SUCH...WE EXPECT THE DEVELOPMENT OF A MIX OF LIGHT RAIN AND SNOWACROSS THE WESTERN PIEDMONT AROUND DAYBREAK SUNDAY...PERHAPS BRIEFLYCHANGING TO MOSTLY SNOW THROUGH MID-LATE MORNING OVER THE NORTHWESTPIEDMONT...WITH A LIGHT RAIN/SNOW MIX ACROSS THE REST OF THEPIEDMONT AND NORTHERN COASTAL PLAIN...INCLUDING THE TRIANGLE...BEFORE NOON. GIVEN THE VERY LIGHT NATURE OF THE PRECIPITATION...WITHLIQUID EQUIVALENT AMOUNTS LESS THAN A TENTH OF AN INCH...ANDFORECAST TEMPERATURES GENERALLY BETWEEN 32 AND 35 DEGREES EVEN OVERTHE PIEDMONT...*WE EXPECT LITTLE TO NO IMPACT*. SURFACES SHOULD BEMAINLY WET...PARTICULARLY AREA ROADWAYS THAT WILL HAVE BEEN WARMEDBY A MILD PRECEDING DAY WITH TEMPERATURES IN THE 50S ON SAT. 

[SnowNiner]

We keep forgetting the temp issues I think, and our good friends the lake lows up north.  Just not very cold, and it's killing us this year. 

 

You know what we could really use?  Some CAD.  Where has that been this winter? 

[deltadog03]

Ok, fire away!!

[franklin NCwx]

^ looks like a good call at this point.

[ncskywarn]

Ok, fire away!!

That's probably about right good call map

[Brick Tamland]

It seems bipolar here. Everyone was excited about the changes in the models, but now people are saying we still won't get snow.

[NWNC2015]

Ok, fire away!!

 

I wish but I don't think there's a snowball's chance in hell I'm getting 1-3" in the foothills Lol.

[deltadog03]

Thank yall!

[downeastnc]

It seems bipolar here. Everyone was excited about the changes in the models, but now people are saying we still won't get snow.

 

Looking marginal on temps, need to have really decent rates to overcome the warm at the surface, even then chances are surface temps at best are 32-35 so nothing sticks.....I think a lot of folks will see flakes but any accumulations will be rate driven and limited to roofs and cars and grass maybe and then quickly melt...need to see temps 3-4 degrees colder at the surface than modeled....

[Tacoma]

Thank yall!

Yep probably only cold enough for all snow in the wnc mtns.

[BIG FROSTY]

Thank yall!

 

Ok, fire away!!

You not working tonight? I see you drinking early tonight! Haha J/K...    Seriously a reasonable looking map!  

[Snowless in Carrollton]

Ok, fire away!!

nice map. I may just go to the NC mountains and see some snow. But if they end up not getting anything I'm going to be mad at you !!!

[NorthernUpstateSC]

Matt Grantham's AFD from Birmingham

--------------------

A PARTIAL PHASE OF THE SHORTWAVES IS NOW INDICATED BY ALL

OPERATIONAL MODELS...AND MORE PHASING REMAINS POSSIBLE. WITH THE

WAY THIS SYSTEM HAS TRENDED OVER THE LAST 24-48 HOURS...WE HAVE

TO REMAIN OPEN TO THE POSSIBILITY OF A MUCH STRONGER SURFACE LOW

AND MORE WELL-DEVELOPED PRECIP SHIELD ACROSS THE INLAND DEEP

SOUTH. YESTERDAY'S NORTHERN OUTLIERS OF THE ECMWF ENSEMBLE MEMBERS

ARE NOW SIMILAR TO THE SOLUTION OF THE OPERATIONAL MODEL. NOW

THESE NORTHERN OUTLIERS ARE EVEN FARTHER NORTH AND DEEPER WITH

SOME MEMBERS DOWN TO 989 MB IN THE EXTREME NORTHERN GULF OF

MEXICO. WHILE IT DOES NOT SEEM LIKELY THAT THESE SOLUTIONS WOULD

VERIFY...THERE IS A NON-ZERO CHANCE THEY MIGHT. ACCORDINGLY WITH

THE NORTHWARD SHIFT IN MODELS...POPS HAVE BEEN RAISED

SUBSTANTIALLY FOR 06-12Z SUNDAY WITH QPF AMOUNTS RANGING FROM

0.01-0.20 INCH FROM NORTHWEST TO SOUTHEAST. THIS SITUATION WILL

HAVE TO BE MONITORED CLOSELY DUE TO THE POTENTIAL FOR DYNAMIC AND

DIABATIC COOLING IN THE EVENT THAT HEAVIER THAN FORECAST PRECIP

FALLS ALONG AND NORTH OF I-20...WHERE THERMAL PROFILES WOULD

SUPPORT RAIN CHANGING TO SNOW...BUT NO ACCUMULATIONS HAVE BEEN

INCLUDED IN THIS UPDATE. THIS IS AN UNUSUAL SITUATION TO BE IN

LESS THAN 48 HOURS OUT...AND ANOTHER SET OF MODEL RUNS IS NEEDED

TO REMOVE THE UNCERTAINTY.

 

This is a valid point with the next system and the systems that follow during the strong el nino pattern. Models today showed  .50 to .75 inches total rain today just this morning for our area in upstate sc. We ended up gettting 1.7 inches of rain, that is 2 to 3 times more then what was forecasted the same day. Models are having a hard time with all the energy that is in the atmosphere.