The 3/3 30 degree temp change sleet/ice event for NC

[superjames1992]

The UK and RGEM have been consistent, they were good with the 2/11 event too. But really all models match up well now. Curious to see 18z RGEM.

 

The 18z NAM is coming in south vs. the 12z run in the very early portions (pretty significant shift for hr 6).  This is a nice distraction while I try to write a paper. 

 

EDIT: The main batch of precip to our west looks slower, too.  Maybe that will allow the cold to build in more?

 

Philly barely gets anything this run.  NYC sees maybe a dusting.  It still should be a fine run for the Mid-Atlantic since it's colder.  The 850 mb 0C isotherm is really on the move this run, reaching the NC/VA border near Mt. Airy by hr 24.  This should be a great run for ROA.

[packbacker]

The 18z NAM is coming in south vs. the 12z run in the very early portions.  This is a nice distraction while I try to write a paper. 

 

SREF precip looks to have stayed the same but definitely colder, 2M line is further south into NC at 18z tomorrow. 

[packbacker]

Coastal NC under WWA, more northern border counties under WWA.

[wncweather]

What are yall thinking for the mountains and foothills of NC?

[Disc]

I just got NAM'd by the 18z. Wow. Colder than 12z as well.

[FLweather]

If this thing keeps shifting south. The sweet spot is going to be from Roa-RIC south to Martinsville, Danville, South Hill

 

Not sure if its just me.. but the timing of this appears possibly off by atleast 3-4hours atleast-faster. Cold air at the surface and aloft are just waiting to come crashing south.

 

 

SLP over middle VA with surface front near Roanoke to Bluefeild east of Nashville TN. As soon as the SLP moves off the coast the backdoor cold front is going to charging south through VA.

[packbacker]

I just got NAM'd by the 18z. Wow. Colder than 12z as well.

 

Yeah, it looks nuts for you, very surprised things are not ticking north, NAM is still north of the Euro, well at least the low track.

[Buddy1987]

The 18z NAM is coming in south vs. the 12z run in the very early portions (pretty significant shift for hr 6).  This is a nice distraction while I try to write a paper. 

 

EDIT: The main batch of precip to our west looks slower, too.  Maybe that will allow the cold to build in more?

 

Philly barely gets anything this run.  NYC sees maybe a dusting.  It still should be a fine run for the Mid-Atlantic since it's colder.  The 850 mb 0C isotherm is really on the move this run, reaching the NC/VA border near Mt. Airy by hr 24.  This should be a great run for ROA.

Hey don't threaten me with a good time hahaha. Love how the Euro is actually dare I say it trending toward the NAM?

[superjames1992]

Looks like a good portion of N NC might get some backend accumulating snow (not a lot, but something) per the 18z NAM.  And sleet, of course.

 

Temperatures are in the low 20s by rush hour, so that ought to be fun.

[packbacker]

The NAM definitely shifted south, the precip shifted south literally everywhere but around DC, they are like a snow magnet.

[packbacker]

Looks like a good portion of N NC might get some backend accumulating snow (not a lot, but something) per the 18z NAM.  And sleet, of course.

 

Much better run than 12z, especially for your neck of the woods.  Wetter and colder.

[packbacker]

If this thing keeps shifting south. The sweet spot is going to be from Roa-RIC south to Martinsville, Danville, South Hill

 

Not sure if its just me.. but the timing of this appears possibly off by atleast 3-4hours atleast-faster. Cold air at the surface and aloft are just waiting to come crashing south.

 

 

SLP over middle VA with surface front near Roanoke to Bluefeild east of Nashville TN. As soon as the SLP moves off the coast the backdoor cold front is going to charging south through VA.

 

 

Agreed, temps are definitely dropping quicker for the MA, but not sure if that translates to us.

[calculus1]

The 18Z NAM seems to drop the 0C 850 line southward in a more traditional linear manner, rather than mimicking the 0C 2m line that has the strong buckling CAD signature.  This would be good news for those further west in NC hoping to witness some wintry precipitation.

 

[packbacker]

NAM has over 2" of QPF for ROA, good grief.

[RaleighWx]

My forecast for this event

[gritsnc]

Ok... where are our snow/ice/zr call map making people?

 

Thanks RaleighWX! I guess I was typing as you were posting.

[superjames1992]

As you'd expect, the 18z Hi-Res NAM came in quite a bit colder, as well.  It's maybe a little south of the op, especially up in the Mid-Atlantic.  Roanoke and Richmond get raked.

[FLweather]

I think the Nam hires has come south too. Which kinda of expected being part nam.(NVM SJ got that)

 

Surface front clears the VA/NC border around 4 am in the morning. With the Rain snow line knocking on the door(va border) around 7am.

 

Brief mix between 10 am and 1pm with full change over to snow here with the Snow line pushing south and east.

 

Not going to say of all of NC but along the border Nam hires would be about 75% snow with its qpf.

[Snowless in Carrollton]

Is there a strong ridge in the southeast preventing the cold from making it to Atlanta ? I notice that Dallas, TX is in the mid 20's in the middle of the afternoon and Atlanta may not even reach 32 degrees AT NIGHT in the next week.

[NCSNOW]

Someone be sure to pin an obs thread before cutting z 's tonight. I'll be at work tomorrow like a lot of folks. Be very interested in ncweather obs then James, kvegas power stroke e.t.c. Hopefully our south VA friends will have already switched to frozen precip by the time the coffee is ready.

70 degrees at 3:52 pm. Hard to believe but exactly 24 hours from now we will be over 40 degrees colder with possible sleet, snow falling.

[packfan98]

NWS in Raleigh has posted their afternoon disco. Good read. I can't copy it well from my phone. Going with wsw for northern border counties and wwa for many of the rest of us I think. Going to be a moderate impact event with early dismissals tomorrow because the transition to frozen is scheduled for mid day to early afternoon at the latest. Probably delays and/or cancelations Tuesday morning with another wwa due to slick spots on roads. Many folks are not going to be happy with this "surprise" system I believe.

[Brick Tamland]

NWS in Raleigh has posted their afternoon disco. Good read. I can't copy it well from my phone. Going with wsw for northern border counties and wwa for many of the rest of us I think. Going to be a moderate impact event with early dismissals tomorrow because the transition to frozen is scheduled for mid day to early afternoon at the latest. Probably delays and/or cancelations Tuesday morning with another wwa due to slick spots on roads. Many folks are not going to be happy with this "surprise" system I believe.

I wonder how long it will take to impact the roads with the warmth today. We have seen twice here the last few years it does not take much to impact the roads here when these storms come induring the day and everyone leaves work at the same time. And I don't think the brine stuff helps much at all.

[Spidyr2k]

Here's the bulk of the RAH disco:

 

MONDAY... CHALLENGING FORECAST DUE TO TIMING/DEGREE OF LOW LEVEL
COLD AIR ADVECTION AND AMOUNT OF PRECIPITATION.

S/WE LIFTING E-NE OUT OF THE SOUTHERN PLAINS THIS AFTERNOON WILL
ENTER THE TN VALLEY MONDAY MORNING THEN SCOOT EAST INTO THE
CAROLINAS BY 00Z TUESDAY. THIS FEATURE WILL AID TO ENHANCE SLY
CONVERGENCE AND MOISTURE TRANSPORT ALONG/INTO THE SFC BOUNDARY.
ADDITIONAL LIFT SUPPLIED BY A TANDEM OF UPPER LEVELS CROSSING THE
REGION. PRECIPITATION APPEARS TO BE A GOOD BET ACROSS THE NORTHERN
PIEDMONT-NORTHERN COASTAL PLAIN MONDAY MORNING...AND ACROSS THE
SOUTHERN COUNTIES MONDAY AFTERNOON-EARLY EVENING.

PER THERMAL PROFILES/PARTIAL THICKNESSES...PRECIP SHOULD BE ALL
LIQUID THROUGH MID-LATE MORNING. GFS BUFKIT SOUNDINGS AND PARTIAL
THICKNESSES/NOMOGRAM SUGGEST PRECIP TRANSITIONING TO PREDOMINATELY
SLEET MIXED WITH RAIN/FREEZING RAIN. THIS TRANSITION ZONES WILL SAG
SOUTHWARD THROUGH THE AFTERNOON...OCCURRING IN THE RDU AND TRIAD
REGION AROUND MID DAY OR NO LATER THAN EARLY AFTERNOON...AND INTO
THE SOUTHERN COASTAL PLAIN AND SANDHILLS BY LATE AFTERNOON. THE FAR
NORTHERN PIEDMONT AND NORTHERN COASTAL PLAIN WILL REMAIN IN THE
SLEET OR SLEET/FREEZING RAIN MIX THE LONGEST. BASED ON PRECIP
AMOUNTS BETWEEN A QUARTER AND A HALF INCH AND A WATER EQUIVALENT
RATIO OF 3:1....COULD SEE UPWARDS OF A HALF OR A LITTLE MORE OF
SLEET ACROSS THE FAR NORTH-NORTHEAST ALONG WITH A POSSIBLE DUSTING
(HALF LESS OR LESS) OF SNOW. HALF INCH OF SLEET MEETS WINTER STORM
CRITERIA SO WILL UPGRADE WATCH TO WARNING AND INCLUDE HALIFAX IN THE
WARNING. FARTHER SOUTH INCLUDING THE TRIAD AND TRIANGLE...EXPECT
MOSTLY SLEET WITH A LITTLE SNOW MIXED IN THE BEGINNING (AND FREEZING
RAIN NEAR THE END). BELIEVE ENOUGH WINTRY PRECIP WILL OCCUR TO
WARRANT AN ADVISORY AS ROADS...ESPECIALLY UNTREATED BRIDGES AND
OVERPASSES...WILL LIKELY BECOME SLICK AND HAZARDOUS. FINALLY...WHILE
SOME SLEET EXPECTED IN THE SOUTH...SLEET WILL BE PREDOMINATELY MIXED
WITH RAIN WHICH SHOULD CUT DOWN ON AMOUNTS. THUS WILL NOT ISSUE AN
ADVISORY FOR THIS REGION AT THIS TIME.

SOME THINGS TO CONSIDER: WARM AFTERNOON HAS HEATED THE TOP SOIL. IF
PRECIP INTENSITY LIGHTER THAN EXPECTED...THEN MOST OF SLEET WILL
MELT SHORTLY AFTER IMPACT. ALSO...IF COLD AIR ADVECTION NOT AS
STRONG AS ADVERTISED...THIS WILL LEAD TO A LONGER PERIOD OF
RAIN/SLEET MIXED WHICH WILL RESULT IN LOWER SLEET TOTALS.
FINALLY...MID LEVELS OF TEH ATMOSPHERE DRY OUT IN TEH AFTERNOON.
THIS SHOULD LEAD TO LIGHT PRECIP AMOUNTS ESPECIALLY BEYOND 20-21Z
WITH HARDLY ANY MOISTURE IN THE FAVORED ICE NUCLEATION ZONE. IF TEH
COLD NOSE IS NOT AS STRONG AS PROJECTED...THEN COULD A 2-4 HOURS
PERIOD OF FREEZING RAIN/DRIZZLE VERSUS SLEET WITH ICE ACCRUAL AROUND
A TENTH OF AN INCH

MAX TEMPS MONDAY WILL OCCUR AT DAYBREAK-MID MORNING ACROSS THE NORTH
AND AROUND NOON-EARLY AFTERNOON IN THE SOUTH. COULD SEE TEMPS
PLUMMET 10-13 DEGREES IN THE FIRST 60-90 MINUTES AFTER FRONTAL
PASSAGE. WIND CHILLS MONDAY AFTERNOON ACROSS THE NORTH WILL BE IN
THE TEENS TO LOWER 20S.


LATE MONDAY-MONDAY NIGHT...PRECIP WILL QUICKLY DIMINISH SW-NE AS
SYSTEM PULLS AWAY FROM THE REGION...EXPECT MAINLY PATCHY AND LIGHT
FREEZING DRIZZLE/SLEET TO OCCUR ALONG AND EAST OF I-95 AFTER SUNSET
WITH SKIES CLEARING WEST-EAST BY LATE EVENING. FRIGID TEMPS IN THE
TEENS WILL FREEZE ANY MOISTURE ON THE ROADS. BASED ON WHAT FALLS
MONDAY AFTERNOON...WILL LIKELY NEED TO ISSUE ANOTHER ADVISORY FOR
ICY PATCHES LATE MONDAY NIGHT INTO TUESDAY MORNING FOR THE ENTIRE
CWA.

[packbacker]

RGEM improved, all frozen around 0.25-0.3" of QPF.

[superjames1992]

The 18z GFS drops GSO from 52 to 22 in six hours during the time period from 9 AM-3PM tomorrow.  Good Lord.

 

The GFS shows 0.5"+ from INT over towards RDU and to the north, but some of that is rain.

[Buddy1987]

^{Was it me or did the GFS not look too impressive. Seems like the 850 is barely just getting through ROA as the heaviest precip rolls through. Looks like it may be a plastering all over everything.}

[mackerel_sky]

My forecast for this event

I like the map and the flirting of the mix for northern most upstate counties!

[packbacker]

^{Was it me or did the GFS not look too impressive. Seems like the 850 is barely just getting through ROA as the heaviest precip rolls through. Looks like it may be a plastering all over everything.}

Yes the low ticked north. 25 miles makes a big difference, I would trust RGEM inside 36 hours.

[Disc]

Buddy1987, on 02 Mar 2014 - 5:00 PM, said:

^{Was it me or did the GFS not look too impressive. Seems like the 850 is barely just getting through ROA as the heaviest precip rolls through. Looks like it may be a plastering all over everything.}

 

Yeah, wasn't fantastic. I'd put more weight on the short term and hi-res models at this point though.

[max100]

Is there a strong ridge in the southeast preventing the cold from making it to Atlanta ? I notice that Dallas, TX is in the mid 20's in the middle of the afternoon and Atlanta may not even reach 32 degrees AT NIGHT in the next week.

Yep, pathetic, huh...It is beautiful out though, who needs blistering cold anymore, anyway?  NC will not be as cold as they think they are either, they are under the same ridge.