3/18-3/19 Icy Event

[Cold Rain]

Need that low to go another 50-100 miles west so we here in the east get dry slotted, do not need rain or ice for that matter....luckily we stay above freezing but the river is running full, all the ditches are just now getting low again and the last thing I want to see is a bunch of rain.

Yeah, I was just thinking that today when I was thinking about when to break down and finally fire up the mower. The ditches are still very wet and the ground is finally starting to dry out a bit. And the weeds are starting to grow with more vigor.

[Jon]

That's not a warm nose, that's a warm forehead. ughhhhh

 

 

[JoshM]

That's not a warm nose, that's a warm forehead. ughhhhh

 

 

Indeed... no snow, it's freezing rain or rain

[superjames1992]

Nope what? No snow and still ice?

 

Verbatim, 850s in portions of central and western NC (not Raleigh... further west) go below 0C for a period of time with a decent amount of precip falling as the ULL does the dirty work, but surface temperatures by this time are in the mid-30s and there may be other layers of the atmosphere that are a thousand degrees, so I don't really know.  Nevertheless, regardless, it's a pretty intense ice storm for some of the same areas hit last time before the changeover to rain.

 

I don't really think snow is our main threat here.  It's IP/ZR.  March ice storms are now the "in" thing.  This will probably be minor, though, IMO.

[Brick Tamland]

Models have consistently been showing ice for the Triangle, though. So any reason people aren't believing them?

[JoshM]

Verbatim, 850s in portions of central and western NC (not Raleigh... further west) go below 0C for a period of time with a decent amount of precip falling as the ULL does the dirty work, but surface temperatures by this time are in the mid-30s and there may be other layers of the atmosphere that are a thousand degrees, so I don't really know.  Nevertheless, regardless, it's a pretty intense ice storm for some of the same areas hit last time before the changeover to rain.

 

I don't really think snow is our main threat here.  It's IP/ZR.  March ice storms are now the "in" thing.

 

and trying to figure out the areas that will receive ZR is tricky (as always), but it will be colder than the last event. More folks will get in on the action. For the second round my best uneducated guess for NC would be Greensboro down to Charlotte and points west, Maybe down to York and Chester in SC. I'm sure it'll be a game time decision

[mackerel_sky]

I don't think it will get any farther south than last time. Same places, less impact, IMO

[superjames1992]

and trying to figure out the areas that will receive ZR is tricky (as always), but it will be colder than the last event. More folks will get in on the action. For the second round my best uneducated guess for NC would be Greensboro down to Charlotte and points west, Maybe down to York and Chester in SC. I'm sure it'll be a game time decision

 

I'd guess the same areas as last time... maybe a little more expansive, but with much lower impacts overall.  We'll see, though; my opinion shouldn't really be trusted.

 

The 00z NAM is coming in colder so far.  Looks like it wants N NC to start as rain with temperatures in the upper 30s rather than the 40s.  Cold rain FTW.  850s are colder with wave #1, too, but there's no noticeable difference between rain with 850s of 4C and 850s of 2C, so it doesn't really matter.

 

Looks like GSO probably goes below freezing at the surface around hr 27, so on 03z on Monday morning (a.k.a. Sunday at 11 PM).  Certainly colder there.

 

Round #2 (if it even happens) is what I'm really "worried" about, though.

 

Round #1 looks good for our SW VA folks.

 

EDIT: Round #2 mostly sucks... maybe a little ZR to start for portions of NC. Round #1 depicts light freezing rain/drizzle overnight Sunday night into Monday morning with temperatures in the upper 20s to near freezing for N NC, FWIW.  Probably more of a nuisance event given that it wouldn't accrete to more than a glaze and the streets will be torching after all the warm weather lately.

[JoshM]

I'd guess the same areas as last time... maybe a little more expansive, but with much lower impacts overall.  We'll see, though; my opinion shouldn't really be trusted.

 

I don't know why I'm so gung ho on this event... I just feel like it'll surprise some people. Hopefully the 0z runs will get a trend going.

[BIG FROSTY]

I'd guess the same areas as last time... maybe a little more expansive, but with much lower impacts overall.  We'll see, though; my opinion shouldn't really be trusted.

I trust you more than NWS dude!   Seriously though, I don't think it will amount to a hill a beans outside Va. unless 00z runs really change my mind... Got to see a lot more cold air.

[mackerel_sky]

The most important question is : what are JBs thoughts ? Or does he not have a thought because NYC is not in the cross hairs!? Can we bring out his spring flags yet? I think it's go for spring after Mon, but 2 inches of rain will be wonderful!

[BIG FROSTY]

Jb says snow for Va. just like all others. If he thought we were in for a Major Ice storm he would hoist the flag just like he did last Ice storm!

not saying he will be right but he sees nothing noteworthy obviously for here.

[JoshM]

One high not enough for you, how about two?

 

http://mag.ncep.noaa.gov/NCOMAGWEB/appcontroller/data/nam/00/nam_namer_051_precip_p24.gif

 

Nice wedge on the SREF too

 

http://mag.ncep.noaa.gov/NCOMAGWEB/appcontroller/data/sref/21/sref_namer_063_2m_temp.gif

 

0z GFS precip type... looks a tad colder than 18z

 

http://mag.ncep.noaa.gov/NCOMAGWEB/appcontroller/data/gfs/00/gfs_namer_054_dom_precip_type.gif

[superjames1992]

NWS RAH just posted WWAs for their CWA.

[calculus1]

GSP also throwing out WWA for their northern tier of counties:

 

[GaWx]

The 0z NAM has 2 periods of mainly light ZR at GSP (3/17 and early 3/18) and it even has one period (early 3/18) of light ZR at GVL/AHN. It misses ZR early on 3/18 at PDK by only 1 degree and it misses ZR early on 3/18 by only 2 degrees at MGE, ATL, FFC, and CAE. This is the unreliable NAM and it is colder in GA/SC than most, if not all models. The GFS and Euro are warmer (though the 0Z Euro with its middle 30's is only slightly warmer). So, I still wouldn't bet on the unreliable NAM at this point. However, it having come back this cold again and with the first modeled ZR period at GSP now starting at only hour 33 makes this a bit more interesting than when it was progged only in the extremely unreliable 72-84 hours out period. Having this close to a sig. ZR at ATL and actually showing some at AHN and GVL is pretty fascinating, regardless, as there has been only one significant to major ZR at ATL that I've found on record after 3/9: 3/25/1971. With this great a CAD winter, I suppose nothing would shock me.

[Tacoma]

GSP also throwing out WWA for their northern tier of counties:

 

why is it that Buncombe is usually left out of these wwa when the elevation is much more than down at the bottom of old fort mtn.

[Blue_Ridge_Escarpment]

why is it that Buncombe is usually left out of these wwa when the elevation is much more than down at the bottom of old fort mtn.

 

Usually Cold Air Damming (CAD) locks in the cold air along the Blue Ridge and just east of there.

[BIG FROSTY]

Looking rough up this way   I'll post pics of my glaze and 3 sleet pellets... 

 

THE NATIONAL WEATHER SERVICE IN BLACKSBURG HAS ISSUED A WINTER
WEATHER ADVISORY FOR SLEET AND FREEZING RAIN...WHICH IS IN EFFECT
FROM 8 PM THIS EVENING TO 2 PM EDT MONDAY.

* LOCATIONS...NORTHWEST NORTH CAROLINA FOOTHILLS AND PIEDMONT.

* HAZARD TYPES...SLEET AND FREEZING RAIN.

* ACCUMULATIONS...VERY LIGHT SLEET ACCUMULATIONS WITH UP TO ONE
TENTH OF AN INCH OF ICING.

* TIMING...THIS EVENING INTO MONDAY MORNING.

* IMPACTS...BRIDGES AND OVERPASSES MAY BECOME SLICK LATER TONIGHT.

* WINDS...NORTHEAST 10 TO 20 MPH. TEMPERATURES...FALLING INTO THE 30S LATER THIS AFTERNOON
REACHING AROUND FREEZING TONIGHT.

 

 

Now if the NAM is anywhere in the ballpark with it's QPF (which I think is way overdone) If we could just get half what the NAM says, Monday night and Tuesday may be a different ball game!
*

[calculus1]

why is it that Buncombe is usually left out of these wwa when the elevation is much more than down at the bottom of old fort mtn.

 

Fritschy, that's your problem here.  The elevation is your enemy in these CAD events.  You've got to face this:  In general, Buncombe county is just a horrible place for wintry weather.  It's too low in elevation, and therefore too warm, during NW-flow events; and it's too high in elevation, and therefore too warm, during CAD events.  The only really decent way that Buncombe county can get a good winter storm is through a traditional gulf-low system that transforms into a Miller A, and those have been few and far between in recent years.

[10below]

I for one am glad no ice storm. Bring on Spring!

[GaWx]

The 0z NAM has 2 periods of mainly light ZR at GSP (3/17 and early 3/18) and it even has one period (early 3/18) of light ZR at GVL/AHN. It misses ZR early on 3/18 at PDK by only 1 degree and it misses ZR early on 3/18 by only 2 degrees at MGE, ATL, FFC, and CAE. This is the unreliable NAM and it is colder in GA/SC than most, if not all models. The GFS and Euro are warmer (though the 0Z Euro with its middle 30's is only slightly warmer). So, I still wouldn't bet on the unreliable NAM at this point. However, it having come back this cold again and with the first modeled ZR period at GSP now starting at only hour 33 makes this a bit more interesting than when it was progged only in the extremely unreliable 72-84 hours out period. Having this close to a sig. ZR at ATL and actually showing some at AHN and GVL is pretty fascinating, regardless, as there has been only one significant to major ZR at ATL that I've found on record after 3/9: 3/25/1971. With this great a CAD winter, I suppose nothing would shock me.

I have since looked at the 6Z NAM and it has even more impressive CAD as well as a stronger NE sfc high of ~1030 mb as of 12Z 3/18. The high's strength has been trending stronger on the NAM. In addition, the qpf for the coldest/crucial 12 hour period of 0Z to 12Z on 3/18 is heavier with about 1/2" in the ATL-AHN corridor. I don't have access to 2 meter temp.'s for this run. However, IF the 6Z NAM happens to be the closest model run to reality, it is going to get very interesting in N GA on Monday night. Amazingly enough, based on my recall of the 3/1-15 daily wx map research I've already done for the period 1969-2003, I believe I can already say that the NAM's 3/17-18 setup of an impressive NE CAD high in combo with a Gulf low is more impressive, than ANY other CAD setup during those 525 days. The 3/6-7/14 setup is quite possibly the only recent 3/1-15 setup that is more impressive going back at least to 1969 due to its 1041 mb high (vs 1030 mb high) and Miller A combo, which we know delivered a big ZR/IP blow to the NC Triad and vicinity. I'm amazed that we may very well have the two best early to mid March CAD setups both within 3/2014 of any CAD setups since at least 1969!! I intend to extend my research of the 1969-2003 maps to include 3/16-20 as soon as I get time.

Edit: ATL has had a major ZR as late as 3/25 (that in 1971). So, although climo would say a sig to major ZR on 3/17-18 would be highly unlikely, it would not say it is anywhere close to impossible. Also, keep in mind that the 3/6-7 event, which was the most impressive looking setup at the surface of any vs. 3/1-15 during 1969-2003 as mentioned, produced the worst ZR in at least the Triad in over 10 years in ANY month! So, the very impressive setup did deliver. It just didn't deliver in a very widespread area as SC/GA CAD areas got away with virtually no ZR. However, it really was a pretty close call in those areas. With another very rare March very impressive CAD/Gulf low setup being suggested at least by the NAM, I'm at least for the moment feeling that the SC/GA CAD areas have at least a nontrivial risk for a significant ZR late 3/17 through early 3/18. After 3/6-7/2014, I thought for sure that that was the last sig. ZR threat for at least N GA. I am fascinated that there's another threat showing up for 3/17-18!

[packfan98]

Fwiw, the 9z SREF plumes for Greensboro look quite a bit colder than the previous run. Increased probabilities of sleet and snow vs freezing rain as a result. Looks like about an inch of precip with the first batch (mostly rain) and about .6" of qpf with the second round that looks to be mostly frozen sleet and frz rain. Bears watching for sure.

[GaWx]

The 12Z NAM has much less qpf in N GA vs the prior two runs during the crucial 12 hour period ending 12Z on 3/18. Also, it isn't as cold at 925 mb. Obviously, that would mean no big deal for N GA. Nevertheless, which such a close call to a sig ZR on the three prior runs, I'll still be following this for N GA at least through tonight's 0z runs.

Edit: The reason for the much lower qpf on the 12Z NAM vs the prior three runs is that the track of the Miller A sfc low is suddenly quite a bit further SE vs the three prior runs. Those 3 runs had the low crossing over the N FL peninsula and then just off of GA. The 12Z run has the low about 100 miles further south when crossing FL and it goes well offshore the GA coast. Based on climo, that normally means less precip over N GA. Let's see if that holds in future runs. The NAM is often a relatively unstable model from run to run.

[Disc]

50 degrees with a winter storm warning for this evening. Not very confident we see warning criteria (4"+) snow up here.

[GaWx]

The 12Z NAM has much less qpf in N GA vs the prior two runs during the crucial 12 hour period ending 12Z on 3/18. Also, it isn't as cold at 925 mb. Obviously, that would mean no big deal for N GA. Nevertheless, which such a close call to a sig ZR on the three prior runs, I'll still be following this for N GA at least through tonight's 0z runs.

Edit: The reason for the much lower qpf on the 12Z NAM vs the prior three runs is that the track of the Miller A sfc low is suddenly quite a bit further SE vs the three prior runs. Those 3 runs had the low crossing over the N FL peninsula and then just off of GA. The 12Z run has the low about 100 miles further south when crossing FL and it goes well offshore the GA coast. Based on climo, that normally means less precip over N GA. Let's see if that holds in future runs. The NAM is often a relatively unstable model from run to run.

I just checked recent Euro and GFS runs. The Miller A low is 100+ miles further north than the 12Z NAM on at least the last two Euro runs and the last four GFS runs in addition to at least the prior three NAM runs. So, for now, the 12Z NAM's track of the 3/17-18 Miller A is a clear outlier to the SE. When considering how unstable is the NAM, this tells me that there is a good chance that the low will trend back NW on future NAM runs and not trend SE on future GFS/Euro runs. Let's see what the 12Z GFS/Euro runs show for the low's track.

[mackerel_sky]

I just checked recent Euro and GFS runs. The Miller A low is 100+ miles further north than the 12Z NAM on at least the last two Euro runs and the last four GFS runs in addition to at least the prior three NAM runs. So, for now, the 12Z NAM's track of the 3/17-18 Miller A is a clear outlier to the SE. When considering how unstable is the NAM, this tells me that there is a good chance that the low will trend back NW on future NAM runs and not trend SE on future GFS/Euro runs. Let's see what the 12Z GFS/Euro runs show for the low's track.

Man, you sound interested in the possibilities for a little more ice action down this way. Can it trend colder ,and give us tree- damaging event in Sc/NGa?

[GaWx]

Man, you sound interested in the possibilities for a little more ice action down this way. Can it trend colder ,and give us tree- damaging event in Sc/NGa?

Well, verbatim the 18z, 0z, and 6z NAM were pretty close to that for N GA and NW SC. However, the 12Z NAM wasn't close and no other models are showing anywhere near the sig. qpf (nearly 1/2") during the period 0-12Z 3/18 that was shown on the 0Z and 6Z NAM. So, the chances are definitely low though nontrivial. The NAM is generally a pretty bad model that tends to overdo qpf in many cases. And like I said, the 12Z NAM has little. Just something fun to watch. The fact that anything like the prior three NAM solutions were produced just makes it somewhat interesting, especially so late in the season, and worth following. But again, chances are low. Don't get your hopes up. If I were a betting man, I'd bet against it.

Edit: the 12Z NAM, IF it were to verify (a huge if), would give CHS over 1" of rain with it only 35-36 on 3/18. That would be a truly amazing event for a place as far south as CHS as late as 3/18! Also, that shows the amount of low level cold available to work with if it were to precip heavily further NW. The CAD this winter has been phenomenal and a dream come true for CAD lovers after a relative absence if it in recent years.

[Ollie Williams]

Winter Weather Advisory

URGENT - WINTER WEATHER MESSAGE

NATIONAL WEATHER SERVICE BLACKSBURG VA

1157 AM EDT SUN MAR 16 2014

...LATE SEASON WINTER STORM TO AFFECT THE REGION THIS AFTERNOON

THROUGH MONDAY MORNING...

.LOW PRESSURE WILL TRACK FROM THE SOUTHERN PLAINS TOWARD THE MID-

ATLANTIC REGION TODAY BEFORE REDEVELOPING OFF THE NORTH CAROLINA

COAST BY EARLY MONDAY. MEANWHILE...COLD CANADIAN AIR WILL SPREAD

SOUTHWARD INTO THE REGION AT THE SAME TIME. PRECIPITATION WILL

SPREAD NORTHWARD ACROSS THE REGION THIS AFTERNOON... THEN CHANGE

OVER TO SLEET AND SNOW FROM THE INTERSTATE 64 CORRIDOR SOUTHWARD

DURING THE AFTERNOON...REACHING THE VIRGINIA...NORTH CAROLINA

BORDER COUNTIES TONIGHT. WINTER PRECIPITATION WILL CONTINUE

OVERNIGHT AND INTO MONDAY MORNING BEFORE TAPERING OFF FROM THE

SOUTHWEST AROUND DAYBREAK MONDAY. SIGNIFICANT ACCUMULATIONS OF

SNOW ARE EXPECTED ESPECIALLY ALONG AND NORTH OF THE HIGHWAY 460

CORRIDOR BY MONDAY MORNING...WITH A WINTRY MIX ACROSS SOUTHERN

SECTIONS INTO NORTHWEST NORTH CAROLINA BY TONIGHT.

SURRY-STOKES-ROCKINGHAM-CASWELL-WILKES-YADKIN-HENRY-PITTSYLVANIA-

HALIFAX-CHARLOTTE-

INCLUDING THE CITIES OF...DOBSON...DANBURY...EDEN...YANCEYVILLE...

WILKESBORO...YADKINVILLE...MARTINSVILLE...DANVILLE...

SOUTH BOSTON...KEYSVILLE

1157 AM EDT SUN MAR 16 2014

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 8 PM THIS

EVENING TO 2 PM EDT MONDAY...

* LOCATIONS...NORTHWEST NORTH CAROLINA FOOTHILLS AND PIEDMONT.

* HAZARD TYPES...SLEET AND FREEZING RAIN.

* ACCUMULATIONS...VERY LIGHT SLEET ACCUMULATIONS WITH UP TO ONE

TENTH OF AN INCH OF ICING.

* TIMING...THIS EVENING INTO MONDAY MORNING.

* IMPACTS...BRIDGES AND OVERPASSES MAY BECOME SLICK LATER

TONIGHT.

* WINDS...NORTHEAST 10 TO 20 MPH.

* TEMPERATURES...FALLING INTO THE 30S LATER THIS AFTERNOON

REACHING AROUND FREEZING TONIGHT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW...SLEET...OR

FREEZING RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR

SLIPPERY ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE

DRIVING.

[NC_WX10]

Not much talk about around here right now. Most not expecting anything?

I think for us near the VA line we coud see some moderate icing out of this.