Sunday snow likely to be a ‘biggish’ deal for SW Virginia
SW VIRGINIA IN HIGH RISK OF 4-PLUS INCHES OF SNOW, PLUS SLIGHT-MODERATE RIKS OF 8-PLUS INCHES AND NEW RIVER VALLEY/MOUNTAIN EMPIRE/I-77 CORRIDOR IN SLIGHT RISK OF 12-PLUS INCHES, through 7 p.m. Sunday, per Hydrometeorological Prediction Center. Also, continued SLIGHT RISK OF 4-PLUS after 7 p.m. Sunday
As hard as it may be to believe after wearing short sleeves and even running my car air conditioner today, I think we’re headed for what I call a “biggish” snow event. It likely won’t be the “big’un” where everyone gets a foot or more, like Dec. 18-19, 2009. But it does appear that a wide swath of Southwest Virginia will be in line for 5-8 inches of snow on Sunday and Sunday evening, with some local amounts possibly reaching a foot depending on elevation and/or where heavy bands set up within the larger precipitation area. I even think the Roanoke Valley is going to get in on accumulations due to the intensity of the heavier snow overcoming surface warmth, though some amounts may be more in the 3-5 inch range at the lowest elevations below 1,000 feet or so.
Timing, to me, is often a harder call than amounts. It appears most of the significant precipitation holds off til after sunrise, though some showers of something may sneak into the southern parts of our area in the pre-dawn hours. Through the day Sunday, there will be periods of rain, sleet and snow, with the all-snow level dropping through the day from highest elevations at sunrise to encompass just about everyone in Southwest Virginia by late morning. There may be a lull or even brief stoppage in precipitation during the afternoon between the first moisture slung northward by the strengthening low and the later snow band with the upper-level low that forms the “comma head” or deformation zone behind the low when it hits the coast. It’s in that deformation zone that the greatest chance for heavy snow lies, and most forecast models bring that right through our area late Sunday afternoon into Sunday night. The heaviest snow still could wiggle north or south some, but it would be difficult to miss us entirely at this point. (At left, HPC map showing probability of getting at least 1 inch of snow by 7 p.m. Sunday — orange is 80 percent, red is 90 percent, dark red is 95-plus percent.)
It hit 64 in Roanoke this afternoon, the second-warmest day in February so far (it was 67 on Feb. 1), 14 degrees above normal, and only 8 degrees off a record high for Feb. 18. How does it shave off half that in the next 12-18 hours?
Well, sub-freezing air is really not hundreds of miles away, like you might think. It’s only a mile and a half away — straight up. Air motion within the storm system will cause lower temperatures to occur throughout the atmosphere, even reaching near the surface in time. That’s called “dynamic cooling.”
Also a factor is that the air is very dry, with dew points running in the 20s this afternoon even as highs were upper 50s to mid 60s. As precipitation starts falling into that dry air, the atmosphere “spends” heat evaporating those droplets and flakes, taking heat out of the air, dropping the temperature. That’s called “evaporational cooling.” Sometimes it’s enough by itself to cool the atmosphere down. This time, it’s only a contributing factor.
Then, there will be some cold air sliding down the east-side of the mountains on northeast winds rotating around high pressure near the Great Lakes. This is called cold-air damming, or a wedge. It is pretty weak in this case, but enough to help a little with the cooling process.
Finally, as the low deepens near the East Coast, north and northwest winds will pull additional cold air along the surface. This is cold air advection. It is not a major factor in getting us from 64 to near 32 this time, but it may help move the needle from near or slightly above freezing to a little below on Sunday night.
There are still ways this storm can go awry, but as time goes along and there do not appear to be major alterations, those ways become fewer in number and less likely. The No. 1 way the snow could come in less than expected is if the surface warmth holds on greater than expected against all four of the factors above. I don’t think it would be a matter of not having snow, but it could delay the onset of snow and reduce accumulations. It does appear this will be a well-organized storm system though, and for an atmospheric machine like that, 30 degrees is not that big a deal to overcome.
February 18, 2012 - 5:47 PM
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I feel like Harrisonburg is going to get shafted.. I would love for it to wiggle further north…. any chance for us?
No comments? Where is everyone? It’s going to snow!!
Kevin, Quags, Howard, and Mr. Griggs – thanks for your thoughts. I’m not concerned for most of the way until that last bit – Fancy Gap to Hokieburg. And Quags is absolutely realistic about what could happen up there. I’m looking at the TN route now – only adds about a half hour but having to go through Chattanooga and Knoxville which also adds more risk even in good weather. Bristol will get ‘stuff’ as well as Wytheville but perhaps less risk of the situations we know can happen on I-77 Fancy Gap. All the warning signs up there…dense fog, crosswinds, falling rocks, and runaway trucks remind us what a potentially dangerous section of road it is. Students and I will discuss options at the awards banquet tonight.
Kevin, I live in the alum ridge area of Floyd county next to little river. Models Are showing that this little area could get quite a bit more than others. Can you explain this and do you think this could happen?
I don’t get how some model predictors and Dave Tolleris are still calling for Roanoke to get 9-12″ or 10-15″ and WDBJ a paltry 2-4″…even though we are in the color coded 3-6″ zone and Kevin you are only calling for a meager 3-5″. What’s the deal with these huge “big un” totals being dished out. I guess my hopes are shot again, however, 4 or 5″ is certainly something….more than the entire winter and I’ll take what I can get!
Hey, wd, I really enjoyed your last comment (#179, at least it was the last one when I looked two minutes ago). I am delighted that you did not stay off the blog until tomorrow, which you mentioned as a possibility a couple of days (and prob’ly 400 total comments here) ago. wd, what do you think of Quagmire’s supercharged snow estimates of late this afternoon on the previous thread? I’ll give my reaction if you will give yours first ….. You and I are among the grand-daddies of the regular commenters here in terms of being familiar with snow over 5+ decades.
Here are a couple of pavement surface temps for comparison.
NBL of I-581 @ MP5.5 Salem Observation @ 02.18.2012 06:22 PM 57.2º
I-77 SBL @ MP 16.9 Observation @ 02.18.2012 06:26 PM 53.4º (Near me in Carroll)
I check later tonight and update.
Scott; I know you’re not below 1,000 feet elevation — that’s where I’m thinking it MAY only be 3-5 (I said generally 5-8 across the region). There is some model support for larger amounts than that. There will probably be a “sweet spot” (or bitter pill for those who hate snow) where 8-12 falls, maybe even a little more. I’m not sure where exactly that lands is really predictable.
Jonathan: Similar to my comment above, it appears likely there may be a fairly narrow zone of larger amounts (8+) develop. Nailing exactly where that will happen depends on lots of small factors that probably won’t be precisely modeled even 12 hours in advance. There has been some tendency to bring a heavier band of snow through about Wytheville and Floyd on some runs, but not on all. Euro put it right over most of Roanoke/New River Valley.
Okay, so I was a doubter on this one a few days ago, but this is definitely starting to look like the real deal.
Anyway, we’re traveling in NC this weekend, staying tonight near Charlotte. Does anyone know what time they’re calling for the changeover from rain to snow? We’re planning to leave Charlotte at 7:30 tomorrow, which would put us back in Roanoke by 11….will that be safe? Thanks!
Soozinne – I had to make a quick run over to my son’s house in Pilot and so was on Beth Ch. I actually pulled over on Coles Knob to use my phone to call about one of the sheep up the road. Saw a mom and 4 kids out on a deck. The Man of the House aka Igor actually was driving so he honked and I waved as I went by. You waved back. Was that you?
wdbrand – I read your comment to Igor – he just chuckled! I actually laughed out loud.
Fire in wood stoves – ready for the snow. Getting excited – probably won’t be able to sleep tonight!
Hokie Trax – drive safe! Let us all know when you get back.
RP: Worst will likely be mid afternoon to mid evening. Some mixed precipitation and snow working in during the morning though. You’ll probably be crossing Fancy Gap. May be some ice or snow there earlier than farther north/lower elevations.
Well here at the Foster compound we are right at the 1000 ft mark, so I will be keeping an eye on it. Hopefully the cold will take hold and I can see some of the 6+ that’s going around.
HokieTrax, I just saw (like 5 minutes ago) a wonderful time-lapse forecast on The Weather Channel for the next 24 hours at least covering the entire East. I strongly suggest you go via Chattanooga, Knoxville, Bristol!!! The changeover to snow on their time-lapse wasn’t until very late tomorrow afternoon for Knoxville, and I think Johnson City, TN, as well. You would have to put up with snow from roughly Bristol northeastward. And as Johnny just posted at 6:41 (more on that in a moment … this may be time urgent, and I will truly go postal if CAPTCHA eats this), the road surfaces are still well into the 50s in SW Virginia. Snow may come down, but melt on contact for an hour or two, meaning 65-120 miles!! I would love to know when you plan to leave and which route you plan to take. More to you in a 2nd comment coming right up.
Thanks Kevin!
If you decide to hold with the I-77 option from Charlotte and Statesville to Fancy Gap, one other thing you can do is get off I-77 at Exit 1 and take a couple of back roads (Route 620/Lambsburg Road east, then left (North) onto routes 690-692/Apple Ridge Road-691 to US Route 52 in Cana, and follow US 52 north (the Fancy Gap Highway) past the Blue Ridge Parkway, then take SR 148 west for a mile to get back onto I-77. Other commenters who live down that way can tell you/us if U.S. 52 is as bad/dangerous as I-77 in a snowstorm, and I would definitely NOT recommend that alternate if you were heading south (downhill) instead of north. The big theoretical advantage to going that way is that I would think that most or all of the tractor-trailers would be over on I-77. If one of them jacknifes on I-77 going up that severely uphill, twisty 7-mile stretch, they can put a halt to the entire northbound (or southbound) traffic.
Roanoke’s temperature still clinging to 56 at 7 p.m. … but the dew point is 19. If it started raining right now, that would probably be enough to pull the temperature at least into the low 40s, without any dynamic effects. Dry air goes up several thousand feet, too, so lots of room in that for some evaporational cooling.
Johnny, your comment earlier on this thread (about the road surface temps) was one of the most valuable I have ever read here!!! TYVM. I won’t be traveling much tomorrow, but such information could be invaluable to travelers like HokieTrax. If you could add a couple of locations along I-81 between Salem and Bristol, that would be even more valuable. I wonder how you found out about it ….
Should I worry that my dew point is already and not drier?
“Well, sub-freezing air is really not hundreds of miles away, like you might think. It’s only a mile and a half away — straight up. That air is going to get pulled to the surface by falling precipitation and air motion within the storm. That’s called “dynamic cooling.”
Sorry…but that does not define the ‘dynamic cooling’ process nor does dynamic cooling ‘pull air to the surface.’
‘Dynamic cooling’ results from strong upward vertical motion which causes a decrease in pressure. Air temperature falls in response to the decrease in pressure (Ideal Gas Law: PV = T). This process plays an important role in modifying mid- and upper-levels within the storm such that…what otherwise would have been rain…is now a favorable environment for snow.
Cold air is not ‘pulled down’ nor is it ‘dragged down’ to the surface by dynamic cooling or resultign from dynamic cooling.. If anything…falling precipitation evaporates which in turn cools the lower levels or maintains cold temperatures in the lower levels enough to support snow.
Prettty interesting slide show from WDBJ7 showing timing of the storm. NRV is clearly in the “mix” at 6AM.
http://www.wdbj7.com/weather/wdbj7-timing-sundays-snow-slideshow-20120218,0,5264882.htmlstory
Jared or Kevin,
Thoughts on Culpeper? I will be back up there by midday, hopefully I will have something positive to report.
Like yall D.Carol, fires built, woods in and don’t have to go anywhere. If it is a ridin snow, I’ll round up my gradyoungens and a passel of neighborhood kids, build several good roadside fires and gettem to sled ridin. They like it when I pullem back up the hill. Lord, times have changed.
**Should I worry that my dew point is already 30, and not lower?
Carol, ya found me! I thought you were a neighbor but no, it was you! Small world….. Next time stop by for tea!
)
NEWxSFC: Your description is wonderful and I generally summed it up as “air motion within the storm” without being more specific. I can find scores of references online to dynamic cooling also being related to cold air being pulled down with heavy precipitation, however, including some from meteorologists. I also did describe evaporative cooling which would seem to overlap your discussion.
Kevin-I am sure you noticed the Winter Storm Warning is in effect for an incredible 30 hours! Even if we shave 3 hours off either side of it, that would still leave 24 hours of accumulating snow. If we get snow for 24 hours (talking NRV above 2,000′ here), how in the world do we not get at least 12″+ of snow? Would it be only because of that “lull” in the precip you menitoned. Seems we may see the old SW VA split and/or dry slotting after all?
NEWxSFC: I’ve read a little more on dynamic cooling and will clarify my description. The “dragging down” seems to be a somewhat faulty description. But in effect, the temperature can be lowered from top to bottom, giving an appearance of being “dragged down.”
If Kevin doesn’t mind me posting, here are some links to some prediction maps that various weather guys have posted.
http://www.facebook.com/photo.php?fbid=301174139942856&set=a.146692722057666.29621.146491555411116&type=1&theater
http://www.facebook.com/photo.php?fbid=10150691785793628&set=a.99611243627.115242.93643233627&type=1&theater
http://www.facebook.com/photo.php?fbid=317236318323633&set=a.148807335166533.25889.129478830432717&type=1&theater
Mike, you have to take into account how long it takes to changeover, then how long it takes to stick on top of how heavy the precip is at certain times, if there is a lull.. and the wet snow will be compacted too.
So, does the fact my dew point is holding steady at 30 matter? Or should I be worried that it isn’t lower like Roanoke’s 19?
Alex, I don’t think you have to be concerned about that. Roanoke’s often runs lower for some reason. And Lynchburg’s temperature usually is colder than Roanoke’s at night. It is already.
NWS doesn’t include Craig in the warned area…does that mean the snow’s going to miss us? We live just into Craig, about 3 miles from Roanoke County and the same from Montgomery County. I’m trying to figure out tonight whether we can go into Roanoke to church in the AM and still be able to safely go over the mountain by 12:30.
So what would it take for this to become a widespread big one?
Mike, I think the winter storm warning has a long duration mainly to encompass the different pieces of the storm. The “lull” that may occur is not unusual when you’re dealing with a low first bringing moisture on its front side and then having the upper low pull in behind the surface low. It is in some ways a 2-part storm.
Is the area back over Arkansas and Texas supposed to fill in later tonight? I thought the stuff to our South now is supposed to move offshore and we get the area of precip that builds in Arkansas and Texas.
Vicki: Craig County is very much under the same winter storm warning.
http://forecast.weather.gov/MapClick.php?lat=37.50972584293751&lon=-80.11642456054687&site=rnk&unit=0&lg=en&FcstType=text
Ben: We’ll get some of what’s south of us, but the precip back over Arkansas and Texas is the start of the “deformation zone” or comma head where our heaviest snow is expected to come from.
So from what I am gathering, you are saying that the best way to achieve some of the higher end totals in Roanoke (like the 8-12″ from DT’s map) is to happen to be under where the heaviest snow band sets up? Pretty crazy how many forecasts I have heard that all have different amounts possible. DT’s is probably the highest I have seen.
My parents came up to Greene for my daughters birthday and were going to try and beat the storm back to Giles in the morning, but they saw the winter storm warning for midnight and decided to hightale it back down 81 tonight! I hope it snows, so they didnt have to leave for no reason!
I think the reason we are seeing such a wide variety of accumulation forcasts is not that there is not general agreement about how much snowFALL there will be, but accumulation. The warm ground, time of day, rate of snowfall, warm air near the surface are a lot of influences on the future accumulation. It’ gonna snow a LOT, but there will be huge differences at any one location in just what piles up in a shady grassy area vs. a blacktop road in full solar exposure.
Hey has anyone mentioned that Mike Seidel from the Weather Channel is broadcasting live from Roanoke tomorrow. We must be in the bullseye.
Another thing about varying snow forecasts is that we’re talking about tenths of an inch of liquid — not really that much when it’s rainfall, but vast differences in perception and impact when it’s snowfall.
Hokietrax…I live about 4 miles from the worst section of Fancy Gap man and can tell ya without a doubt you don’t want to be coming up that stretch of I-77 (actually all the way to I-81) if big snow (or even little one,for that matter) in that area. I was stuck for over 3 hours during a snow shower last month when that clipper came over less than 1 mile from the Galax exit. As Doug mentioned the back roads (US 52) are MUCH better to travel when snowy out there. After 20 plus years driving to deliver calves and such around here in snow,the one thing I learned was to avoid the interstate at all costs!! If you do decide to come this way tomorrow I would be happy to talk you through the best way to avoid backups if they are present. Let me know on the blog and I can give you my cell number if needed. Good luck and travel safe
Quagmire – We need your “last call” snow total predicitons! Are you still confident in end to end snow (no mixing, no warm nose, no dry slots) with 12″+ for the NRV, like you were around noon time today? Any changes?
And I always thought the best example of evapoational cooling (or dynamic cooling) was to slowly turn a can of beer or bottle of wine in a bucket of ice to get it down to drinking temperature faster!!
Even I think you have minimal early mixing there, Mike.
Kevin, have you thought about sending Mike Seidel a tweet or FB message and inviting him to your blog?
Clarkdocvet: Many years ago my brother got stuck in a winter storm at the Hillsville exit off I-77. He had an offer of a warm place to spend the night in Galax and could not make it that far. He spent the night at a gas station next to the interstate. The roads are treacherous in your are in bad weather! As I mentioned on the previous thread, I drove from Roanoke to Galax and back today; lovely drive. I wouldn’t want to do it tomorrow!
HokieTrax: Please let us know when you arrive safely in Blacksburg. We are all hoping you have a safe trip!
Kevin, are you going to have updated snowfall amount probabilities for the area or just stick with the 3-5″/5-8″ that you mentioned in your blog post? Just wondering! Going to be a fun day tomorrow.
I’ll put it in right here as a bonus to all the folks who read the comments:
Roanoke
<1 10 percent
1-2.9 25 percent
3-5.9 40 percent
6-11.9 20 percent
12+ 5 percent
Blacksburg
<1 5 percent
1-2.9 15 percent
3-5.9 25 percent
6-11.9 40 percent
12+ 15 percent
Jared,
What are your thoughts for up our way in Greene, Madison, and Culpeper?
Dumb question, but why does the NAM always show more precip than GFS, etc? Just curious, but it always seems to be on the liberal end of the spectrum?
Also, what time do the new models come in?
Leo Lady: Glad you enjoyed
your trip to Galax today,and yes,that was our Veterinary Clinic you passed. Should have stopped by the Caboose across the creek and taken your dog for a walk! That is one end of the New River Trail State Park that follows the old railroad bed to Fries and Pulaski. My father started that clinic in 1966 and we have been ther ever since.
Awesome, thanks Kevin!
Had a hard time deciding between giving a little extra weight to 1-3 or 6-12 for Roanoke. Might should have gone the other way with 25 percent for 6-12 and 20 percent for 1-3. Maybe even 30 percent for 6-12 and 15 percent for 1-3.
Just a guess anyway. 5-8 with locally 12 works for me. I threw the 3-5 thing in just because I know how it seems to work down here near the Roanoke Times where I work. I call this the officially least snowy spot in SW Virginia.
It is currently 42 F up here on the ridge in Dopplerville aka the Doppler Radar site southwest of Roanoke. Just walked one of the dogs and it is so quiet and still out there.
Soozinne – if I am not in a hurry next time, I will stop for tea.
wdbrand – What do use to pull everyone back up the hill from sledding? Sounds like a fun day for the grandkids.
Time to step away from the computer for the evening and try to calm down. Just so excited! TeeHee!!! Will check back in tomorrow with a report from up here on the ridge.
I think this storm may be like the March 30th snowfall in I think it was 2005. It was VERY VERY heavy and about the wettest, warmest accumulating snow I can remember. It was infamous for doing widespread damage in Roanoke’s trees and bushes. Bradford pears all over the valley snapped like twigs with the weight of that 6-7″ that the valley generally received. I think power lines were affected too. It was a mess and I see similarities with this one, however, this one is over a month earlier than that and the high today was 64, which is warm enough, but that snow that fell on Sunday, March 30th had a previous day high of a downright hot 76-degrees and the snow stuck and it did stick on the roads quickly too! It was even in the 40s when it started to snow and stayed in the upper 30s most that day…so still shocked it accumulated like it did!
“NEWxSFC: I’ve read a little more on dynamic cooling and will clarify my description. The “dragging down” seems to be a somewhat faulty description. But in effect, the temperature can be lowered from top to bottom, giving an appearance of being “dragged down.”
The original analysis concluded (paraphrasing) ‘cold air only a mile or so above the ground would be pulled down to the near-surface level and enhance snow chances.’
This is a common misconception about the physical processes at work…which to your credit duly acknowledge. It’s a faulty conceptual model which as you note…is often recited by meteorologists. We all know; however…meteorologists are in the ‘being wrong’ business.
The suggestion was precipitation was dragging down cold air from aloft when in fact nothing is being ‘dragged down.’ Pressure in the column is being reduced which stretches the column ==> a lowering of the freeze level.
Good times…
http://www.easternuswx.com/bb/index.php?/topic/24814-forecasts-for-dynamic-cooling/page__view__findpost__p__267011
Surface temp of 42 up there when the precip starts, Carol, and I think you’d go to snow within an hour, if not start as sleet/snow. It should be colder by morning, too.
Is it just me, or does the NAM not look very good?
0z NAM…. Uh oh.
So a friend just bet me $20 that it will start snowing in Roanoke before 2am.. Was that a safe bet?
I thought it was a no brainer myself.
NEWxSFC: We are all in the weather learning business here, starting with me, every day, every storm system. Dynamic cooling is a subject I can return here and/or in my print column to explain in more detail. Thanks for pointing me to a clarification.
Here are a couple of pavement surface temps for comparison.
NBL of I-581 @ MP5.5 Salem Observation @ 02.18.2012 09:02 PM 54º
I-77 SBL @ MP 16.9 Observation @ 02.18.2012 08:56 PM 50.7º(Near me in Carroll)
I-81 @ SR 682 (Rural Retreat)2012-02-18 08:56 PM 52.3º
I will check again in the a.m. Not going to drop off much until precip starts.
Our temps. aren’t heading down very fast(still 53 at 9pm) is this cause for concern or as expected? Still not sold on this snowstorm.
The 0Z NAM indeed takes the heaviest precipitation just south. Still brings .25-.50 amounts to about US 460 corridor, perhaps 2-5 inches of snow if it all stuck. Let’s see if it’s repeated on later runs before jumping to conclusions. Even the big Dec 18-19 storm had 1 run less than 24 hours out that hiccuped and seemed to take the storm to the east.
Thank you for your calm and collected nature, Kevin. You saved me from having a heart attack just now ha! Although I’m praying that the GFS and other later runs don’t follow suit…
Oh god.. I hope the 00z NAM isn’t right…. I would cry.
Scott: I think you win that bet.
George: If temp is in mid 40s by precip time I think it will be fine for changing to snow not much later.
Snow fans in Greensboro are cheering the 0Z NAM run!
I’m praying that the 0z NAM is wrong!!!! I was thought this was a slam dunk!
Ouch, that was not what I was expecting to see from the NAM. Hoping that is not a trend.
Anyway, is the GFS even worth looking at any more for the storm? Isn’t it used for mainly mid-long range?
GFS is short and mid range model.
Not that I looked at the 0zNAM or could read it if I looked… I’m just basing my opinion on the comments! I’m hoping for lots of snow!!! Here is to a great snow day!!!
When does another model run so it can be compared to the NAM? I don’t understand how it can shift so suddenly.
Here we go again! Oh well!
GFS runs in another hour or so.
During a storm, having a dashboard of radar images to look at is helpful (if not just pretty to look at).
The Blacksburg NWS office along with storm spotters and radio amateurs have setup a cool website to
give an overview of the weather at http://www.wx4rnk.org/wx_brief.html
Check it out!
@Kevin thanks – I think he is crazy to think that it’s going to snow before 2am. Looking at the models and the air temp, its not likely. I am downtown and air temp is really nice and only need a light jacket.
another clown map…. would be nice if this verified….
http://wxcaster4.com/gfs/CONUS2_GFS0P5_SFC_ACCUM-SNOW_48HR.gif
Kevin: Please tell me this storm is not a bust! I just went outside to feed the big dog and it felt really balmy. I come back in and read comments that the OZ NAM in not good. Yikes!!!!!!!! My dog and I have been looking forward to this snow for days. We are going to be extremely disappointed if it does not happen.
Clarkdocvet: I am a little familiar with that portion of the New River Trail and would have loved to take my aging four pawed friend for a walk there. He wasn’t with me on the trip today. Maybe next time.
There are quite a few on DT’s facebook complaining that the radar looks terrible. Any thoughts on this? I personally don’t know what to look for to tell.
I keep reading about this “NAM” model. Before it was showing super high amounts and now it appears not so much? But could we dismiss this change seeing that we weren’t placing so much stock in this model in the first place?
can someone link this NAM model from tonight please? thanks….
http://www.wunderground.com/modelmaps/maps.asp?model=NAM&domain=US
for the non-NAM folks….watch the rainbow colors go BELOW Virginia. That’s bad for snow lovers
48-hour precip map from the NAM probably best tells the story:
http://tinyurl.com/783x3kj
Oh, the excitement! I absolutely adore the technical banter when we get close to some kind of a weather event. Now we have pavement temps added to the mix! I have no clue what the 0z NAM is, I always think of the wizard behind the curtain in ‘The Wizard of OZ’ – HA! Thank you to all the regulars who share their expertise with us.
Not looking good. Boy how fast things can change.
The current radar looks terrible. No phasing – what is with that huge gap between the main precip shield in GA, and the stuff back in OK/TX? I don’t like the idea of a two part storm, with “a gap”. I can just sense the ole’ SW VA split and corresponding dry slot coming. That kid on you tube called it last night – remember he said something about those folks around Roanoke, might want to be concerned about the dry slot. The only thin worse than the dreaded I-81 Mtn. Empire warm nose, is the dry slot. Sorry folks, no one is getting more than 8″ in VA out of this.
From what I see: no snow anymore! Thanks for the link to the map, Kevin. Paraphrasing the doll on the island of misfit toys in “Rudolph, the Red-Nosed Reindeer” I’m going to bed and dream about next winter. Nite, all.
Please tell me this is all a dream..with the current radar and the NAM.
It was forecast to be two areas of moisture, what’s new about it? Most of our moisture is coming from the ULL when it transfers to the coast anyways. I hope the NAM isn’t right though about it going that far south..
My predictions
150 Comments 25% chance
200 comments 50%
250 comments 15%
300 comments 10%
Kevin, how do newbies (like me) interpret shifts in the models? Is a later but contrary model the one to go by, since it’s closer to the event, or should later/contrary models still be interpreted in the context of the earlier models that pointed in the (more or less) same direction? Thanks.
Here’s what an earlier run of the NAM today said the radar should look like about now:
http://tinyurl.com/73fl3te
And here’s what it looks like about now (10:02 pm):
http://radar.weather.gov/Conus/
Not impressed :/
I figured it’d find some way of screwing up.
I’ll wait for the GFS, but the storm looks so anemic right now..
So… What does that mean?
Leo Lady: Even that “bad” NAM run I posted doesn’t show NO snow this far north. It shows less snow — except right smack down on the NC line. Might be good for Stuart and Martinsville snow lovers.
The projected and current radar pics don’t look hugely different to me. Phasing between the systems really wasn’t evident on the earlier NAM run till after midnight.
What does that mean?
Well this sucks! Winter Weather Advisory for us up here in Greene after having a Winter Storm Watch all day! Im done with this winter! This has been really pathetic and miserable for us snow lovers!
Quagmire DO YOU COPY!!! I repeat Quagmire DO YOU COPY!!! Please save us! This storm is falling apart right before our eyes.
lol
Kathy: You may have been asking about my comment about “phasing.” There are 2 pieces of the storm that are projected to come together to make the bigger storm. They appear to be separate now on radar. However, earlier model projections didn’t yet show them coming together now. I was just saying I’m not sure the storm looks a lot different than it’s supposed to now.
Omigosh!! One model run comes in with a much different-looking prediction, and “everybody” (OK, that was an exaggeration) starts claiming the “sky is falling,” so to speak. Hang on, snow lovers. No need to panic unless the other models start agreeing. If that happens this close (time-wise) to the onset, then there is real alarm. I can just imagine how “everyone” will be shouting with glee if the GFS comes in robust again for SW Virginia. Brace yourselves …. I have lots to say in a few upcoming comments. I sure wish wd would sign in during the next few minutes with his thoughts about Captain Glen Quagmire’s huge prediction.
Thanks to Clarkdocvet, Griggs, Kevin, and all blog friends for helping us Hokies know our options to get home. We have decided to leave at 230 AM Auburn time (330 AM EST) and go up I-75 by the way of Chattanooga, Knoxville and enter VA via Bristol. I think some of our other VA groups are doing the same now. I DO understand about Fancy Gap and the detour is worth the extra miles and time. I know we will hit this stuff but the risk is less this way. I’m sure I-81 will be pre-treated and treated during this too. I will report in as I can when we make stops.
Please try and calm down people. This was one run of one model. Everything appears to be going as forecasted so far. The storm is not “falling apart in front of our eyes.”
Now if the phase fails to happen, then I’ll worry.
Kevin, What are your current projections for tomorrow morning going south on 81 from Northern Virginia down to the NRV around Christiansburg? I’m trying to figure out whether to leave tonight and travel all night, or wait it out to see what things are like around 6 or 7am?
There will probbably be some light precipitation on I-81 from the NRV south at sunrise, slowly spreading over the area. A lot of it won’t stick on roads at first, being both light and roads holding heat.
I didn’t really think you were supposed to look at the GFS this close to an event anyways.. isn’t it usually a mid-range model?
There is one immense plus about this storm system, but it is not about this region. Sure, if we get a lot of snow or sleet or even rain, it will help delay or avoid a drought from starting here. But this system has already doused lots of Texas, and it is just now dumping tons of rain on another state that desperately needs it ….. Georgia!!! If Texas had not had such a once-in-a-lifetime type drought over the last what? .. 18 months or so, The Weather Channel would have been shouting constantly about how exceptional the drought has been in Georgia. Most of the Peach State has been dark brown (worst level of drought) for the past couple of months. Luckily, it has gotten this bad during the time of the year (late autumn and winter) when the effects of drought are less severe than in spring and especially summer. They might have been headed for a bad spring brushfire season (maybe that has already been going on there??), but this will help them big time.
who knew that poor Kevin would have to be a meteorologist AND a therapist? We all need to get a life.
How is it looking for Botetourt? Daughter just had surgery and really wants to see some snow. I hope the last model was wrong!
Brandon-it is falling apart in the sense that the phase is no where close to where it was supposed to be right now. In Kevin’s link above comparing the model radar for right now (from last night) and the actual radar from right now, there is a noticeable difference. In the model there was precip covering Mississippi at this time, meaning the phase was about to occur, but right now Miss. is nearly bone dry! The first part of the storm is getting ready to exit stage right, while the second part is getting hung up over the Arklatex. This is not good.
Been watching all day and not posting. This recent NAM info about made me keel over. Glad I have the rest of you to calm me down, or worry with me. Come on snow!
GFS is short and medium range model. Whether it’s a good one or not is a matter of opinion. Weather service tends to use the GFS more than other models.
Haven’t seen but I’m told the Canadian model still looks the same as it did before.
HokieTrax, thanks for checking in. And a huge TY to clarkdocvet, for telling about I-77. That bearded guy who does television interviews for VDOT — Jason Bond, I think — has said in one interview recently (perhaps he has stated it many times before) that if VDOT was planning now where to build I-77 in Virginia to connect Charlotte/Statesville, NC with Wytheville and central West Virginia, there is no way that it would be built where it is today. Now have a safe trip up the “I’s” HokieTrax — I-59 to Chatta, I-75 and I-40 to Knoxville, then up I-81. I’m gonna feel like 2 cents if you run into a road snafu going that way, at least if it is southwest of Fort Chiswell, VA.
GFS is the SAME!!! oh no!!
Not quite the same. More moist up this way — .5-.75 inch line gets to Roanoke/Blacksburg, which would be 5-8 inches IF all snow and IF it all stuck. But it’s a little more south too. So it was at 18Z.
00z GFS is further south too
Mike Seidel better head down and get a hotel in Danville, or Elon College!
Great.. Lynchburg is now in 2-4 inches, and half of that probably won’t even stick..
One tiny request, HokieTrax …. please call me “Doug.” When I had the same postal route for 6+ years, I would introduce myself to folks and say my name, and invariably they would question me about my last name …”Briggs?” “Grigg?” “Gregg?” probably because of my Yankee **&^(**&ng that!! “New England” accent (being originally from Boston, I DESPISE!!! the NY Yankees!!! LOL and no apologies to Yankee fans, either. LOL) Anyway, I would spell out Griggs, then wisecrack, “Yeah, I know ….. I need to buy a vowel.”
Kevin, so with the recent changes in the model’s Roanoke city is looking closer to an estimated 3-5 inches of snow, right?
It will be interesting to hear what gets said at the top of the hour on the big 3 stations.
I don’t think anyone knows whats going to happen next!
Wow that’s a wicked looking line of storms going across south Georgia! As a snow lover, at this point this winter I’ll be happy with 3 inches. Three days ago I didn’t expect we’d get much of anything. As Kevin has said many times, the atmosphere is going to do what it’s going to do (speculating is fun however…lol).
If Monday was not a holiday and if I had to deliver my postal route “monster” on Monday, I have to admit that I might be chuckling a bit at this point. I would claim that my SH Vice Chairman Sam Oakey had come through with his snow deterring voodoo and also I would be claiming other anti-snow malarkey. Especially in previous winters, when I got treated worse here by a few folks. But I am truly disappointed for the 90+% here if this turns out to be a decent but no longer a 6+ inch event for most of SW Virginia.
NAM snowfall.
http://wxcaster.com/gis-snow-overlays.php3?STATIONID=FCX
Not feeling it. Dry slotted again. I’m moving.
HokieTrax…be safe driving back
Cville4…you can try http://www.aviationweather.gov. When you input the airport code, you will have to use the ICAO code i.e Charlottesville KCHO. Basically put a K in front of the airport identifier. When I get time, I’ll give ya some website to look at for avweb.
QUAG’S FINAL CALL WILL BE OUT SHORTLY. I AM NOT LIKING WHAT I SEE ON THE RADAR. Also Brandon just brought a serious point of the jetstream not phasing. I need to verify some data I will be back shortly.
Taking the NAM very literally, I would suppose that would be about a 1-3 inch snow for Roanoke, figuring in some mixed precip, rain and non-sticking snow at outset. The GFS could still be 3-5 inches or even a little more.
On the other hand, a little farther south solution would probably mean colder air penetrates earlier, so there might be less mix/rain at the outset.
Thanks Kevin, I just saw WSLS changed Roanoke totals to 2-6 inches. It will be interesting. Though if it only accumulates 3 or so inches it will be gone by Tuesday.
This winter makes me want to cry..
Stick a fork in ME, I’m done. Can’t stand this back and forth. Going to bed and leaving the phone and computer in the other room so I’m not tempted to look at anything weather related for the next 9 hours or so. Lots of pouting going on in this apartment right now.
I just drove past Monticello on my way home with the window open (it’s still somewhat pleasant out, if cooling down…) and it definitely has that “snow smell” out there.
Has anyone ever wondered why snow has a smell thats different than from rain? Looking forward to a little bit of snow, as i spent all day in the office. I can take monday off with little guilt.
Will do *Doug*! Appreciate your looking out for us. I’ve gone into protective Mom-mode to make sure my students get home safely. They have been a wonderful group. This trip will be memorable for all the rain, for getting to go into the impressive Auburn stadium last night (we had an Auburn connection!), them winning an award, and for the possible adventure/snow on the way home.
Earlier many questioned why the local mets were so slow to jump on board. I would say the answer is experience. In the 3-4 years I have been following weather blogs here and at accuweather, it seems like there is almost always a shift in the last 24 hours, which is why several of us have commented on not being in the bullseye 2-3 days out is often better. It really seems like the best chances of getting a big snow are when we are forecasted just for a small snow, and we have the good fortune of being in the direction of the last minute shift that brings more snow. I really hope I am wrong, and we get what has been forecasted ealier, it would be fun to see a big snow.
Well, wd didn’t sign in, but I will. If GQ’s forecast of snow falling right through until Monday morning, I wouldn’t have that big of an issue with his snowfall total predictions from his late-afternoon comment with his forecasted totals for every community. And thanks, GQ, for going to that much effort. I got a taste of what that can be like when I did the research for the history of the NAO last weekend. But I did have one major disagreement with one part of your comment, namely that it would be all snow from beginning to end. With surface temps at 64 degrees here in the floor of the Roanoke valley this afternoon, there was and still is NO WAY that the initial precip would be snow. It (the snow) would melt in the bottom layer of the atmosphere. The best scenario (and I think KM mentioned this yesterday or Thursday) for a maximum snowfall would be for a layer of sleet to coat the ground initially, which would allow all future precip to accumulate as snow. We have seen this scenario before, by the way. Kevin has even mentioned many months ago that models (OK, “some models,” perhaps) still have trouble accounting for relatively warm surface temps.
Looks like the server is not handling all the traffic to well.
Hey, HokieTrax, LeoLady deserves a thank you also, so here is mine to her. She mentioned a bad experience in the Fancy Gap area, too.
One theory on the south trend, that Keith Huffman of Lynchburg suggested to me (actually saying it might happen before it did) is that the northern piece of energy with the storm is stronger than modeled. And that nudges it south.
There’s still snow on there, folks. If it snows even some don’t forget to enjoy it, snow lovers. It’s been a long, mild winter, and this might be the last go-round for another 10 months. And snow haters — it’s gone by Tuesday.
Kevin what’s your take on the model shifts tonight? are they a hiccup or a sign of things falling apart for snow lovers. Would love to see 4 plus inches in the noke, is that still likely?
Excellent comment, “Dad of 6,” at 11:17 PM. I just saw Jay Webb (who is my favorite “7″ meteorologist, BTW), and he did not even adjust his snowfall totals since the 6 PM weathercast for ROA. In fact, if his forecast “verifies,” as KM is wont to say, Rick of Wytheville will definitely need the plow attachment on his tractor. Wyhteville was the bullseye on Jay’s map, 4-8 inches. Happy, Rick??
Kevin,
In your opnion, does the move south affect snow totals for Pulaski? More or Less than the 4-8 ?
Doug Griggs & Sam Oakey strike again
FROM QUAGMIRE WEATHER BUNKER CENTRAL URGENT IMMEDIATE BROADCAST MESSAGE…
QUAGMIRE OFFICIALLY CALLS BUST TO THIS STORM…I REPEAT…STORM IS BUST
EXPECT ONLY 1-4” MAX IN VIRGINIA NOW AS THE STORM WILL MOVE TO OUR SOUTH. Thunderstorms robbed us again & the surface Low will go due east not ENE.
Will explain more Sunday as I will make one final analysis before I announce my retirement of amateur weather forecasting. I’m closing up shop for good. Kevin will more than likely tell ya what went wrong. He’s better at this than I am. Until Sunday
Still liking my chances either way. Gettin cold fast up here.
I want to see if the European agrees with it, and whether the later NAM and GFS continue the trend, or nudge it back north a bit again.
The GFS would not change much south west of Roanoke, like in Pulaski. The NAM would lower totals everywhere but the southern sliver of counties next to NC — could boost it for Martinsville/Danville.
My guess is the NAM is too extreme but there is a bit of a south trend. There was the day before, remember, when it looked like the bullseye was Charlottesville.
Thank you LeoLady and Doug. Hey, who on the blog had the cat that forecasted snow? Cat got all crazy before it snowed.
SO much for that Bullseye being Charlottesville! These models just mess with your mind! Might as well just watch out the window to see what happens!
Quagmire – that was me (10:36pm post) pointing out the fact that the phasing seems to be lagging WAY behind, based on radar trends showing massive dry slot over Miss. right now, and the rest of the moisture in GA/SC seems to be exiting stage right and sliding right underneath of us. It is not showing any signs of making the turn. Looks like a true southern slider in real time (forget the models now). I assume you are knocking your totals way back (no chance of 12″+ in NRV now)?
When the bullseye was Cville alot of weather folks said it would likely be more north in reality. Dont think Henry M’s Latitude theory gonna work out on this one.
We had a warm high of 58 here this afternoon.Its now down to 37 and the wind is starting to pick up with a windchill i would guess in the low 30`s right now.I have been checking out the radar tonight also and the first batch of Rain is moving east,at least thats what it looks like to me.I still don`t think we`re gonna get much up here in Northern Fauquier this time around.
Whether this means anything or not, the radar for Mississippi is beginning to show signs of “filling in” precip.
That latest loop from NWS kinda shows it: http://radar.weather.gov/Conus/southmissvly_loop.php
Blacksburg Mike…
You are correct. I-64 south 2-4″ with higher amounts along NC border.
Zach’s nightmare has come true. There is no way that dry slot will fill back in. By the time the coastal low develops it will be too far east for any phasing to occur.
Also, I just checked the temps at 1000, 850 & 700mb. Way too warm even if we get strong dynamic cooling, it won’t be enough.
I am such an idiot for not paying attention sooner to the radar & Satellite. I should have called this Bust 3 hours ago when I saw the radar.
The low dewpoint / dry air was remarkable today. Every time we touched the laptop…ZAP…shocked.
42* with dew point of 32* here in Woodlawn. Maybe for one being in the southern part of the NRV will pay off and we still catch the northern edge of the storm for some decent snow. NWS still has us in the 4-8″ range.
The moisture moving beneath us moving off the coast wasn’t what was supposed to give us our snow.. it’s the ULL behind it that was supposd to phase with the energy in the midwest, but isn’t doing so yet..
Well, others have beat me to it. Sometimes at this point in an event, a “picture is worth 1000 words.” Radar. I suppose other websites have radar that cover a massive area, but I like wunderground’s. Just enter a city anywhere in SW Virginia, or Georgia for that matter, then click on the radar graphic. That will give you the radar with about 125-mile (?) radius. Then click on the phrase ‘regional radar’ above the radar display, and suddenly you have a radar covering many hundreds of miles. Put it into motion, and one can quickly see what has been happening recently …. precip moving due east, practically no northward movement at all. Now certainly it will edge northward over the next few hours, but not at the pace needed to provide us with a fairly biggie, unless something changes again.
boring…boring…boring…hope all of you snow-haters are happy. now onto the bland and vanilla existence…spring-mild…summer-mild…fall-mild…winter-mild…where is that sense of adventure???? was thinking a big one was going to happen here, but looks like we are going to miss it. will be nice to see a few flakes on sunday though.
Fork is out of the drawer and ready to go. Still a chance maybe some light accumulation, but this looks south and yes to warm.
As KM said if we get some snow falling and a little on the ground I will take it all in. The only thing that can make up or this last year+ of little snow is a nice mild summer.
Quays, I think your assessment is a little extreme.
Alex makes a good point – - this stuff was supposed to out run us. Dont pay attention to it. The ULL behind it still has to track, and will pick up some gulf moisture likely tomorrow.
Talk about temperature-sensitive snow amounts! Looking at NOAA Snow Accum. map for Sunday, you could use it for a topographic map as well. All the snow gradients are stepped just like topo lines.
http://www.erh.noaa.gov/rnk/emer/emer_winter.php
As for my call: I think here at the base of Bent Mt./Martins Creek, we get about 5 inches on the deck/grass and barely 2 on the road. It’s just too warm.
I also have several deer bedded down in the backyard right now; 20 feet off the screened porch. I know that cows lie down before it rains. What’s the wives-tale on deer? And coyote howls? Have plenty of those as well…
Forget the models from here on out. We are within 12 hours of when the snow was supposed to start. Just look at the RADAR! This is not good. No one in VA will see more than 3″ max, and that will only be the higher elevations of Grayson/Carrol counties. I am obviously very dissapointed, but this was still fun. Kevin and Quags thanks for the excitement, but this baby is over!
Kevin,
Didn’t I read on a previous thread that similar storm tracks historically had a northern bump at the end of the event, compared to what the models depicted?
Keep hope alive
KEEP HOPE ALIVE
Canadian model still showing .5-1.0 qpf in central ans south side va. I’ve always liked our northern neighbors…Ay
Calm down fellow snow lovers and back off from the ledge! TWC saying recent model runs suggest part if swva could be looking at a foot of heavy wet snow. Said around 6 in. for Roanoke and that whats his namewould be on scene in the morning.
I think everybody needs to go to bed and get some rest and look at things again in the morning. That’s what I’m about to do — after putting up a short new post.
This ones different. No neg nao. Not runnin up the coast like it supposed to. I’d wait before I call it. My temps and dewpoints are about to concur in the 30′s. I think the radar may do things it doesnt usually. Could be wrong but it all just looks different this time. Aint sposed to get good till noon Sunday couple runs ago.
It’s funny, anthony o, but I have the exact opposite take on the weather here in SW Virginia over the last 26 months. Incredibly exciting. Brutally cold and snowy winter (“heaven” for many of you) in 2009-10, followed by an incredibly amazing turnaround with record early April heat in 2010, hottest summer ever in Roanoke in 2010, incredibly cold December, January, and first 1/3rd of February last winter, then wet spring, then still another brutally hot (and in my neighborhood, DRY …. remember when I became the Mayor of Brownsville?) summer in 2011. I am grateful that things have settled down a bit over the last few months. OH, and I forgot to mention the devastating tornado season last spring, too. I have lived in Roanoke area since October 1997, and the last 26 months have been the most eventful BY FAR.
Kevin, 12:09 Am comment …. OK! Will do. After looking at the new thread. :>)
SoRoCo Ben, I always heard that deer tend to bed down before a snow storm and move around little.
Low already strengthening and trying to jump to the coast. Not good.
Alex – - it is the ULL in Mississppi bringing us our weather. It’s coming. Check the stuff hapening over Kentucky right now – - thatll happen tomorrow. I would be worried in Lynchburg, 6″ is pushing it. I’d say more 2-4″ , but it’s still snow.
Deb, if the deer are any indication, then I think we’re in for some white stuff. There are now 5 total, all bedded down and munching their cud. I can hear their teeth grinding from the deck. And a rather skittish raccoon thrown in for good measure. Some nights, it’s a veritable Wild Kingdom out here, although I always liked the Wild World of Animals theme song better.
For you children of the 70′s:
http://www.youtube.com/watch?v=jDlKaG24CPU&feature=related
like i said, bland and vanilla…happy presidents day!