Friday evening snow thread: Plume of moisture on its way toward cold air over SW Virginia
A plume of moisture is on its way through the Tennessee Valley toward Southwest Virginia, where temperatures are cold and likely to support snow and sleet later this evening. A few bullet points for the evening:
* Winter weather advisories now cover Patrick, Floyd, Roanoke, Botetourt, and Rockbridge counties westward. Western Bedford and northern/western Franklin counties may see similar conditions to the winter weather advisories just west. I would not be surprised to see these advisories advance eastward and southeastward a bit later.
* We’ve batted around 1-4 inches for the last couple of days for likely accumulations, at least from Roanoke north and west. No reason to change that now. General rule on accumulations in Roanoke Valley and points north and west: Expect 2 inches, some will get a bit less, some a bit more. 4+ looks unlikely, unless there is some sort of heavy band that sets up over one area for a long time.
* Clouds today have held surface/low-level temperatures well below forecasts, with highs in mid 30s to near 40. In a marginally cold situation, this can make all the difference. More will likely fall as snow and sleet. There may now be little or no rain at all from Roanoke west and north.
* Area of precipitation looks solid and fairly intense. It is moving very fast though. May arrive in I-77 corridor by 9 p.m. and overspread region near midnight. You can follow it on Radar-Future Cast.
* Speed of system may mean most of the significant precipitation will be over near sunrise, no later than mid-morning. Melting will commence soon after it stops, with highs likely poking into the 40s most areas on Saturday. But Saturday morning is likely to be slippery in much of our region.
December 28, 2012 - 4:05 PM
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Weather blogger taking a break til 7 p.m. Gonna get some rest after little sleep last night (sick child) and likely little sleep again tonight (winter weather). If you comment … it won’t pop up til after 7.
Quags is out of the office til Saturday mid-day. Flying back home from Boston to RIC before the snow hits. Enjoy the snow!
Hope your son feels better. I have been battling a sinus cold all day while taking all the Christmas decorations down and tripped down the stairs toting a miniature tree….OUCH! Anyway, Kevin, do you think the WWA may be bumped up toe Winter Storm Watches for Roanoke/Botetourt!All we need is 4-inches to fall which doesn’t sound too off from their predictions of 1-3″. It is colder today than anticipated and keep hearing all this talk about the NAM being more impressive…???? After the day I’ve had, I need a snow to pick me up!! It’s nature’s liquour…the quicker picker upper!
Okay Kevin – Rest up! Power came back on here right before 2 pm this afternoon. It almost made 36 hours off. Washing dishes and clothes while we have power and preparing for Round 2. Went into Christiansburg today and bought 2 sets of headlamps (to wear on your head so you can see). We figured that will help next time if we want to read when the power goes out. Preparing for Round 2 that will arrive later this evening.
Oh no! Noticing a fry slot in the moisture. Keep that away from Giles!
Never made it above 39* here in Galax today…that dry slot waaaayyyy out there in NW Alabama looks like it is heading right for me here in Woodlawn.Bet ya it gets me!!
wdbrand – thanks so much for the offer of a generator but we got one. We only fire it up for 4-6 hours at a time and that seems to work.
Went to Galax today for a funeral/graveside service. Luckily the sun came out for a while, as it was cold standing outside. We came back to Roanoke on rt. 221 and saw many power trucks working through Floyd County. It looked as though some were working on current outages while others were staging for the storm tonight. I am an ardent snow lover, but I hope it is not too bad tomorrow morning in Roanoke as I must be out in it. I like snow better when it is not mixed with ice and sleet and when I don’t have to be driving in it.
Wd, thanks very much for asking about our poor, weak old doggie. I e-mailed you back, BTW. For the rest of you, he (Blondie-Boy) spent another night at the vet clinic, which cannot be good. I am at home now, waiting to hear what today’s verdict is about whether we get to bring him home.
Back to weather: I agree with you completely, wd, and although I haven’t looked through all the comments on the previous thread (I just read yours at 11:32 AM), I bet KM agrees about whether an area has snow or even slush cover will have a signif impact on snow/sleet amounts. Right now I am very skeptical that it gets above 42 tomorrow in Roanoke city. I have been wrong a zillion times on this blog …. this is one of those times when I hope I am wrong (about that).
Kevin you think I can make it from rural Fincastle to a Smith Mountain Lake family dinner by 1 p.m. on Saturday? A lot of cooking is riding on this!
OK, I have looked at today’s comments now. I will emphasize even more, just as wd mentioned, that whether an area already has snowpack (yes, even a tiny one) or ice or slush on the ground is a HUGE factor in what type of precip will occur and for how long frozen precip occurs. Just like wd and probably several of you folks, I have decades of experience of this stuff. It is why I am often skeptical of model snowfall forecasts when the ground is bare. {Please note: I typed “often,” not “always” nor “nearly always.”} The snow/slush/ice on the ground greatly influences the temps at the surface, thus allowing snow that hits the ground to start piling up immediately, instead of melting on contact.
One other thing: one factor that will influence those of us who have to work outside tomorrow is the big increase in the wind speeds as the precip departs and the day wears on. Now here is something that I don’t know about weather: does a big wind help or hinder the melting of wet snow?? Or maybe it is irrelevant?
34 degrees and still falling in Bonsack @1250 feet. Looks promising!!!
That dry slot is destined for my little valley here too, how much you want to bet?! Bring on the “winter goodness” aka SNOW!!!
I noticed that Ft. Lewis on the Salem side still had quite a bit of ice on the trees this evening just prior to sunset. If we get more freezing rain, then snow on top of if that could spell trouble for those trees!
Hooray Dopp Carol for getting power back on. Headlamps are great – I use one when camping/backpacking.
All the main roads here in Hokieburg have been brined – the tell-tale stripes so at least VDOT is expecting something. It feels like snow and my sinuses are letting me know some is on the way.
The drive to OH Saturday may be interesting and white. Making sure an extra blanket is in the car, my Bean boots, extra provisions. Any other suggestions?
Well, we are gonna be between two lobes of the storm system, two different pieces of low pressure — so it is sort of a dry slot. That’s part of why we’re expecting pretty low precipitation amounts.
But what you’re seeing on Blacksburg radar isn’t it. That’s just a space between two patches of precipitation moving out ahead of the main body. If you look at Morristown Tenn radar, the precipitation is solidifying more in NE Tennessee, actually increasing a bit.
Does look like some precipitation knocking on Wytheville’s door, crawling up I-81.
Cathy; Roads should be improving by mid to late morning. Is that enough time to get you from Fincastle to SML?
Pulaski County is showing 31 with a blob moving in.
Siri doesn’t think it’s going to snow tonight.
Moisture is the question mark, more so than the thermal profile. 2 days ago I thought it would be the other way around.
Rain reported at Rural Retreat and 36 degrees. That’s not unexpected. Deeper cold air is generally pooled farther east. Or at least that’s what we think …
It’s raining on the Hokies in Orlando right now. Really coming down.
29 here on the “ice covered” ridge at Dopplerville. Guess I better get the dogs out for one last walk before the precip starts.
Hokie Trax – maybe a small shovel thrown in the trunk for your trip north. Have a safe trip!
Kevin or Griggsy….I missed the last 3 days in my winter weather data for highs and lows….the 25th-27th, could someone give them to me please! Thanks!
Critical to whether these snow forecasts verify tonight is whether the precipitation shield building northward west of Knoxville, out of Alabama toward Crossville, spreads our way later, right up I-81. That is where the moisture for accumulating snow would come from. The stuff entering Southwest Virginia now is preliminary to that.
I meant to mention earlier today that this morning at 6:30 am when we were starting the generator for its morning run, there was this huge ring around the moon. It was gigantic. Will need the cleats on the boots the next time we go out – a little slippery.
Just getting ready to go to Manassas to my dads for the night.Its 32 and getting cloudy.Calling for 2-4 inches for Northern Fauquier County.Have a great weekend everyone and enjoy the snow.
Freezing rain and 32 here.
Scott: Here’s a site you can go to get highs/lows anytime.
http://www.erh.noaa.gov/rnk/climate/f6/html/F6.html
For Roanoke, those numbers are 53/37 on 25th, 42/33 on 26th and 42/30 on 27th.
Finally. Gotta lil sleet in southeast Grayson County. Its bouncin’ and rainin’. We’ll see. Still dont like the radar.
Got some snow too. Whooo. Not gonna be a bigun, I know but Whooooo.
Just looked at NWS-Blacksburg’s weather balloon readings from 7 p.m. tonight — it shows above-freezing temperatures about 1-2 miles up. But there are also some really low dew points in that range. It would suggest precipitation beginning there as freezing rain and/or sleet and then likely changing to snow with evaporational cooling in those warmer but drier layers.
Here is the sounding if you want to take a look. Red line tracks temperature, green line dew point, changing with height shown on left (in kilometers)
http://www.spc.noaa.gov/exper/soundings/12122900_OBS/
Hello everyone!
Long time since I last posted but I am still following the blog very regularly. Has the wretched “Gotcha Code” disappeared?
I am not liking the looks of back end of this storm with rain soaking into sleet/snow followed by temps in the low 20′s. Sounds like a recipe for a glacial mess lasting into the new year. We still have a fair amount of ice on the trees here.
Doppler Carol, got my power back on around 7:45pm but holding my breath after we got it back for just one glorious hour yesterday between 5:30 and 6:30pm. (Folks, I had the pleasure of finally meeting Carol earlier this month and she is every bit as nice in person as she is on the blog.) Had been nursing the generator since Wednesday.
To follow up on my comments about Sierra Snow from the Pineapple Express that Kevin quoted me on earlier this month, here is a link to an article about a National Geographic Documentary about keeping I-80 open during the snowstorms in the Sierras. http://blog.sfgate.com/ski/2012/11/27/hell-on-the-highway-the-story-of-i-80-at-donner-pass/
Interestingly, when they were getting ready to film, the snow didn’t show up on schedule as snow didn’t make much of an appearance last winter in the Northern Sierras. Trust me, as bad as the roads can get here, I have seen much, much worse except for freezing rain. Freezing rain was a new experience for me when I moved to Floyd County. Needing to spend more time in California due to aging parents who need more assistance so following weather more closely out west now.
Happy New Year y’all.
Very light precip. Some flyin’ some bouncin’. Nothing on either deck. You almost gotta hear the sleet and see the flurries.
At least I got to see a lot of snow today! We traveled from Missouri to Wytheville and drove within a few miles of Albion, IL which had 19″ on the 26th.
yay for the Doppler Gal!!! Electricity.
Thanks for helping SS with the highs/lows, KM.
Indian Valley John, IS THAT REALLY YOU?!?!?! If you are asking about the Gotcha Codes, it HAS BEEN a looooong time since you posted! Great to have you back, amigo. How have your dogs been?
IVJ, I got to meet Doppler Carol at the NWS Open House on November 10th. I agree completely with your opinion of her. Also got to meet HokieTrax, who is likewise very friendly. Too bad that i could not have met you there.
I was really surprised at WDBJ7′s forecast model shown by Brent Watts. It also showed a dry slot about 11PM, with the precip not resuming until 2 AM as best I could tell. It also showed only rain for Roanoke area by 5AM, maybe even 4 AM. If it showed any sleet during the wee hours, it was very brief, because my eyes could not detect it. It really ticks me off how fast they run through the hours with that forecast model.
It’s still a borderline, disorganized storm system, after all.
There is a dry slot from SW corner of Virginia toward Nashville now. It’s how much the stuff around Knoxville builds northeastward that will determine if we get adequate moisture.
Getting some reports of sleet in Pulaski County now with these initial showers.
I wish anybody who ever doubted our radar technology was here with me right now. No Virga here, LOL. If its green its doin’ somethin’ if it aint its not. I know I know,, the dewpoints. But its funny.
All very fine sleet. No Flurries.
Last night I posted some forecasts for Copper Hill in NE Floyd County. I just looked up the latest NWS point forecast for that community, and it shows a low of 30 from 5 to 7 AM. However, that same timeline of temperatures shows that it will be 30* at 10 and 11 PM, rise to 31 for the midnight to 4 AM timeframe, etc. Well, that is plum wrong, because on the first page it showed the current temp there as 34. Unless the current temp is wrong. So one or the other is wrong.
It also shows temp rising in CH to 35 by 10 AM and to 37 by noon. Winds climb hourly until they peak (for Saturday, that is) at 21 mph at 3 PM, with gusts to 33. If there is ice on tree limbs, look out below.
I am watching a blob of rain that entered Wythe County and then moved into western Pulaski shrivel up before my eyes. That is, assuming that the NEXRAD radar I am looking at is portraying reality.
Hey, Other John, are you at home or nearby? If so, any precip at your house yet?
I see what you mean Kevin, some light stuff in Pulaski but looks like a dry-slot for awhile after that. I need all the help I can get since I am traveling tomorrow.
Felt some sprinkles just a little bit ago just east of Blacksburg. Air temp at my property just a little above freezing.
Hey, Kevin, the Roanoke Times doesn’t have a sports blog, does it? I would like to make quite a few comments on tonight’s Russell Athletic Bowl. Virginia Tech won, 13-10, in overtime.
Amazing. I just opened another window, clicked on wunderground’s NEXRAD radar for Roanoke (which is really centered extremely close to Doppler Carol, of course), then switched to the Regional view, which covers as far west as east-central Tenn, well west of Knoxville. That radar shows everything (all precipitation, that is) NE of Knoxville as being sleet or freezing rain (bright pink on the display). So I may have been wrong when I referred to that blob of rain that entered Wythe County …. it may have been sleet/mixed.
I know all the snow lovers are jealous but it aint all that exciting, it’s still very light sleet but the flurries are back. Still nothing on deck.
Slot filling in? Kevin, you explained it might not be our typical jump ya dry slot. I’m probably wrong.
Kevin, why is there no winter weather advisory in either Smyth or Tazewell counties……surrounded by counties that are expected to get significant sleet and snow?
Nothing yet 2 miles North of Town of Pulaski @10:10
All sleet but pickin’ up. It’s pretty steady now.
Dopp Carol – I was thinking the same thing on the shovel. I always have a small folding army-type shovel in the back but maybe the snow shovel is not a bad idea. I’ve never traveled very far in snow weather.
I need a de-fib after watching the Hokies tonight. Michael Hoback…hope you were doing okay if you were watching it.
Smyth and Tazewell counties are Blacksburg office forecast area, counties to west and south are Morristown, Tenn., forecast area. Appears to be a slight difference in opinion there, or perhaps slightly different tendencies on when to issue advisories.
Doug: Times has multiple sports blogs. You may want one of these:
http://blogs.roanoke.com/aaronmcfarling/2012/12/rutgers-virginia-tech-in-game-blog/
http://blogs.roanoke.com/andybittervirginiatechfootball/2012/12/28/halftime-rutgers-10-virginia-tech-0/
Posting new in next several minutes looking at the dry slot issue.
I hate these type storms…….before the tech game, the talk was, 2 to 4 inches possible…WWA should be moving east..etc.etc…..I get hom from watching tech game, and now….we may get some sleet…….. wdbj 7 just showed maybe a “coating” of snow..I mean come on!!! I really don’t understand why anybody (including me) gets caught up in any of the hype, before it starts starts fallin! Don’t know anything more than we knew 72 hours ago……good night all..and I can promise u one thing…… the is 100% of a chance of something happening….or not happening…..ta….da….!
uggghhhh! Lol
31* with a dew point of 26 in Woodlawn. Heavy sleet here for past 20min or so…looks like the dry slot is staying north of here,right up 81 for now…
You can look at it like that, if your interest is only whether it snows or not … or you can look at it as the interest and intrigue of the atmosphere and what it does.
This has never been advertised as anything other than a borderline and disorganized storm system. And it remains so.
Well starting to become less concerned about dry slot issues south of 81 and more of mixing issues. Heavy sleet now in CC and looks like a pretty good slug will slide right up along those counties south of 81. question is what type of precip will it be.
Where is “CC” located?
We have sleet in Salem. Not heavy but you can hear it!
Started sleeting in Salem.