Palm Sunday snow? Probably
The first full day of spring never saw the freezing mark at Blacksburg — 30, recorded at 1 a.m., was the coldest high for the date (previous March 21 record 31 in 1996) and also tied for the second coldest high on record for an astronomical spring day (tied April 7, 1982, with record of 29 on March 31, 1964.) Roanoke’s high of 37 (12:13 a.m.) was 2 degrees above the daily record of 35 set in 1914. Snow squalls combined with the arrival of the extremely cold air relative to the season led to some slick roads in parts of the New River Valley this morning. Lows 
in the upper teens to low 20s likely won’t set records tonight (if it gets a little colder, Blacksburg’s March 22 record of 15 from 1986 could be pushed), but will be about 15 degrees below normal. Temperatures will slowly moderate the next couple of days, but won’t get close to the mid to upper 50s that are normal for late March.
While the spring cold snap — which shows no signs of relenting significantly through the end of the month and perhaps into early April — is a significant to historic event in its own right, much more attention is being focused on whether or not Southwest Virginia reaps an infrequent widespread spring snowfall out of this unusual weather pattern. The approaching weekend storm system has some similarities in its expected general evolution to the one that affected Virginia with rain and heavy snow on March 5-6, with an inland storm to our west transferring energy to a coastal storm, what in weather geek talk is often called a “Miller B.” That storm left heavy amounts of snow — 10-20 inches — on much of the state from I-64 northward and along the Blue Ridge westward, but dropped lighter amounts in our region — 2-5 inches in the Roanoke Valley and just north, less than that in the New River Valley, zero to the south. Here are the important differences. (1) The overall pattern is much colder, even though it shouldn’t be climatologically three weeks later, because of the extreme high pressure blocking over Greenland and the North Pole. (2) The inland low is expected to be farther south, tracking east or northeast through the Tennessee River Valley,r ather than diving southeast through the Ohio Valley as on March 5-6. (3) The coastal low is expected to organize farther south, off the Carolinas, rather than off of the Virginia capes. (4) The storm appears to be not quite as wet as the March 5-6 storm. (5) The coastal storm is not expected to become as deep as the March 5-6 storm. Add these factors up, and the first three in particular lean a little more to snow for Southwest Virginia than March 5-6 ended up being. There will likely be a “front-end thump” of precipitation as the inland low throws Gulf of Mexico moisture into cold air. This may happen in the morning hours Sunday, which would mean the entire night would have allowed the air to cool from Saturday afternoon highs projected by the weather service in the 40s to low 50s, and most forecast models do show cold enough air to support snow wedging as far south as the Virginia-North Carolina border. 
It’s possible some residual warmth near the surface could limit the snowfall in lower elevations, and the higher spring sun angle is often a factor during daylight hours when precipitation is not especially heavy, so many forecasts will reflect a possible mix of snow, sleet and rain. Later, as the coastal low takes over, a back-end “deformation zone” of snow behind that low is likely to spread over the region late Sunday afternoon into Sunday night, perhaps even Monday morning. In between, there may be a lull in the precipitation, or even some light rain or sleet.
So here is the takeaway: It is probably going to snow Sunday, at least some. There will be some fine-tuning of details to determine a reasonable guess as to how much at any given location. On the upper end, I think it’s possible there could be a widespread 4+ event — so does NOAA’s Weather Prediction Center. It would be the first such event in spring since March 30, 2003. On the low end, it could just be some slushy snow giving way to rain/sleet/snow/ick mix, or the other way around, the ick mix giving way to a little wet snow at the end. I think it’s going to be difficult for the region to entirely miss snowflakes, but questions about the duration, intensity and surface temperatures leave accumulation projections very much in flux. My thinking now is toward the middle, a 2-5-inch type snow in the Roanoke and New River valleys, mixed with some sleet and maybe rain at times in the early to middle part of the event. Even that would be a notable event for late March. The higher up you are in elevation, and the farther north and west of Roanoke, the better chance of seeing several inches of snow Sunday into Monday; the reverse is true headed lower in elevation and south and east, though I think just about everyone sees flakes for some period of time.
There may be another system with snow potential around the March 31-April 2 period. Too far out to say that for sure, but a Palm Sunday/Easter doubleheader for snow would be some way to start spring after such a quirky winter.
March 21, 2013 - 7:53 PM
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Keep trending south keep trending south
Kevin nailed it above…nothing more to say. Enjoy the extra innings of winter coming up.
I’ll take a stab at snow predictions Friday afternoon.
Hey, Jared, this comment is from my heart, and hopefully it echoes the sentiments of many bloggers here. I am glad that your dad survived the wreck in Giles. Icy roads are the absolute worst. Is he basically OK?
I have to go do an errand. When I return I will give the latest on the polar view, unless someone else does it or Kevin has posted a link above. I am sure that it still shows very strong block over Greenland.
bring on the snow! full time snow lover(hate summer, sorry guys) ready for something worth discussing. bedford has certainly been evaded by the snow these last few months. i just want a little something before the heat wave hits and with the flakiness of this winter, i really feel like we’re going to get it this summer!
Have been to Richmond this week. Went across Afton Mtn on Monday with heavy icing on every surface. Still had some left over sleet/snow in the mulch at Short Pump Monday Night. Went into the 60′s Tuesday, 50′s Wednesday and 40′s today. Came home to a high of 31 at the Chapel. Too cold for spring. Now the threat of snow and ice and mush. This is too much. Our forecast is for snow tomorrow night, rain on Saturday Night and Sunday and Snow and Rain mixed from Sunday Night through Wednesday. Now Kevin is hinting for more on Easter. So much for the sunrise service. Also, its going to be ‘bone cold’ tonight. At least this weather is keeping the bud at bay.
Snowstorm in full force in the Missouri Ozarks tonight, with up to 5 inches already reported. This is the first wave of the complex storm, but it’s a secondary piece of energy that holds our snow chances for Sunday.
From a NRV’er now in Alabama… Weird weather here headed your way! NWS in Birmingham has snow aloft tonight but lower atmosphere too dry to make it to the ground. Then the scenario sets up for really bad thunderstorms Saturday/Sunday, By the time it gets east, it will hopefully just be snow. We’ll be dodging the threat of tornados instead.
Doug, talked to my dad just awhile ago. He said just some damage to front bumper. Had to get a tow truck to help get him off the top of the guardrail and then he was on his way. Guess that’s why they say Ford Tough!
UNBELIEVABLE! I can’t believe the late season snows Arkansas has been bestowed as of late. They have beat RRA seasonal totals I bet. What is Roanokes official snow reading thus far this season Kevin? I’m thinking a foot or a hair more with possible more to come….I HOPE!!
That would be AWESOME if we had a WHITE Easter Kevin!! Wow, just thought of this…the masters golf tournament won’t be the same without everything in bloom! Is Augusta, Georgia pretty cold relative to normal as well?
11.8 at Roanoke, 18.1 for Blacksburg on 2012-13 snow totals. A 6ish snow would both places close to normal.
Roanoke finally nosed a little above Little Rock, which is at 10.6 inches and safely south of the snow zone tonight.
On the one hand, I am sooo ready for spring, but as a snow-lover…I can’t help but get my hopes up for another shot at a snow event! I’ll definitely be following this blog closely over the next few days!
Just throwing this out there. Has anyone noticed how the last two runs of the GFS take the low at the 9Z Sunday time frame and jumps it NW by about 75 miles?
18Z GFS clown map is pretty much in 2-6 inch range through Roanoke/New River valleys.
http://wxcaster.com/gis-gfs-snow-overlays2.php3?STATIONID=FCX
If these heavy snow totals verify for the mountains of NW Virginia, I have to wonder if some of those places will be near record March levels with a third heavy snow event this month.
As in the low at 12Z is about 75 miles NW of the low at 9Z. Do we really see this system throwing it in reverse for 3 hours or so???
I’ve noticed that NW jump on some of the models, Snowville. I’m wondering if it’s more of a redeveloping low-pressure center with additional energy moving in. It’s pretty diffuse to start with, anyway.
Kevin, rain or snow , what time frame should this weather event get started for the Roanoke Valley?
The cooler Saturday the better for snow right?
I don’t think we see much til after midnight in the wee hours of Sunday morning, and maybe not til close to sunrise. Generally, a colder Saturday is better for the early precipitation to be all snow, but even if it gets to the low 50s, it won’t necessarily derail snow chances altogether.
Weather.com saying 58 for the Noke on Saturday???? Then a snow event? Craziness!!!
If you want to follow it at the surface … go here
http://www.weatherroanoke.com/surface.html
I agree with low 50s not messing it up. When I used to live in Nashville, I would want the prior day temp to be no greater than 45. But here, we get the advantage of CAD (cold air damming) east of the mts. It can be amazing, and is often underestimated by models and forecasters. But, this late in the season … ya gotta wonder. I remember the 2003 Mar. 31 snow … depths were very elevation dependent. I happened to be at Smith Mt. Lk. with about 2-3″, Roanoke seemed to get 3-4″, but I could see hill tops getting 6+”. It could be that way this time as well.
Heavy frost here in south Georgia, along the coast no less. Very odd for so heavy a frost this late in the season in this part of the world. Another heavy frost forecast for tomorrow morning. One more week here and I get back to DC and civilization soon enough!! Cold or not, the Nats begin their World Series run in just over a week.
Weather.com is the only outlet going that high on Saturday.
I would agree, Wally, that it will almost invariably be in some manner an elevation-dependent event. Higher elevations will get more accumulation. That’s usually true with near-32-degree snow events.
First of all, you were right Kevin to correct me about Saturday’s high for Roanoke. All I remembered was that there were two consecutive days with highs in the 30s for Roanoke on WDBJ7′s weekly planner. The two days are Sunday (high of 38*) and Monday (39*). DBJ is predicting a high of 54 for Saturday in ROA. That may sound warm compared to the past 5 days including today, but it isn’t, really. If it verifies, it will still be at least 6 degrees below normal.
Hey, Kevin, while I go look at the polar view, do you have enough information about the March 30, 2005 snowstorm to compare and contrast it with this one? And maybe c-and-c it to the March 5th-6th event, too? Is this one looking basically similar to the 3/2005 storm, or quite a bit different? {I had 5 inches here, at my 1400+ foot elevation on 3-30-2005)
wow we are going to get another half of an inch of snow just like we have all winter long WOW.
I keep seeing comments about the nasty Gulf thunderstorms that could form over the weekend, and as a snow lover, I get concerned. I keep thinking back to March 26, 2011, when 3-6 inches looked good here but then Gulf t-storms “stole” our moisture or basically blocked moisture from coming northward. Then the northern piece of that system went through WV…basically SW VA got shafted on March 26, 2011.
Which brings me to question if these t-storms this weekend could ruin our snow chances.
You mean 3/30/03? It was a much different setup than this. An Arctic cold front slammed into the back of the precipitation shield from a coastal low, and dynamic cooling from the deepening low also aided in rapidly dropping the freezing level. The previous day’s high was 76, and it went from 43 to 32 in an hour, after a thunderstorm passed through.
if its this cold sunday night watch out 28 here in bedrock
Wow about the polar view. Over the past few days I have seen stuff there that I have never seen before. The first thing that caught my eye is that the blob of green warm air over the North Pole has merged with the one over the west side of Greenland. My guess is that this feature would reinforce the block and the cold air coming south. And there is now a swath of dark green air (which is warmer than pale green air, according to the color code) cutting right across the middle of Greenland, too. I don’t remember seeing dark green yesterday.
The vortices. The stronger one on the Western Hemisphere side of the pole continues to be over the Arctic Ocean coast of the Yukon, but extends west over the North Slope area of Alaska, too. I don’t know, but I bet Barrow Alaska is going ridiculously cold now or in two days compared to whatever their normal is. The vortex that has the most influence on our weather is centered over the Saint Lawrence River valley of SE Canada, just north of New England. Still dark or bright blue at the heart of it. One can clearly see the huge trough that has settled over the eastern U.S. The palest shade of blue extends all the way to South Caro., the 2nd lightest shade is over N.C., and the 3rd lightest shade is over Virginia. There is no 50-50 Low right now, but that could change. If the bright blue area over Quebec City moves east, it will be a 50-50 low.
Thomas: I see you are in Goodview. You have gotten less there a couple of times it’s been more not far away. Maybe it’ll break for you this time. Who knows.
Yes, sigh. 3-30-2003. Thanks KM for your reply and 2nd correction. I’ll blame these mistakes on being overtired. (The real cause is my age, but I am in denial right now …..)
Kevin – Any idea of when all this cold wintry air will start to move out and finally let some warm 60-70 degree weather come in!? Im so anxious for it to get warm again.. Tired of all this cold weather.
No firm idea on that, Hope. Some chance the March 31-April 2 storm I mention above takes an inland track and starts to sweep out the colder air. Or it may be forced south and threaten snow again. There really is no clear indication yet of when the cold snap will relent.
3/29/03 I lived in Forest Edge subdivision at the base of Bent Mountain on 221. I distinctly remember cruising around south county in a little convertible, top down, only to be shoveling about 5″ of heavy wet snow less than 24 hours later. That was a shock to ones system.
One thing that could hold temperatures down on Saturday is that the disturbance over Arkansas tonight may track through the Carolinas, spreading some rain down that way. The new NAM (still running, not quite out to winter storm time) even dribbles a little of that precip into far southwest Virginia. If it spreads some clouds over us Saturday the temperatures may not get as warm as forecast.
New NAM (0Z) is stronger with the inland low and therefore warmer. We would transition quickly through snow to sleet and rain at the outset, then have a long lull, and then back to snow when the coastal low deepens. Doesn’t look like it would be a big accumulator — you might get an inch or two on the front end, then wash it away, then get some more on the back end. North of Roanoke would have potential to stay snow longer. Here’s a peek.
http://mag.ncep.noaa.gov//Image.php?model=nam&area=namer¶m=850_temp_mslp_precip&cycle=00&image=nam%2F00%2Fnam_namer_066_850_temp_mslp_precip.gif
Looks a lot like March 5-6 except it is colder to start. NAM isn’t really in its wheelhouse yet, within 48 hours. An interesting run, if not what a lot of snow fans want, exactly. it would snow, and then be a slushy mess.
Actually … the 0Z NAM clown maps are coming in a lot thicker with snow, hammering us on the front end, at least from Montgomery and Floyd counties northeast. I must have underestimated how much is snow looking at the 850 mb charts.
http://raleighwx.americanwx.com/models/nam/00znamsnow_SE072.gif
http://raleighwx.americanwx.com/models/nam/00znamsnow_NE072.gif
i hope the nam is wrong for snow we need it to stay cold knowing our luck northern va gets it again and we dont get but a dusting and rain i hope thats not true i want a foot or more
Some people in Arkansas who follow weather closely are noting that the GFS has clobbered the Euro with respect to the snowstorm there tonight, with the NAM in second place. Heavier amounts occurring, farther south penetration, like the GFS. Doesn’t mean a thing for our Sunday chances, but just interesting to note that the Euro doesn’t always win.
dt has us at 20pecent chance of 12 inches and 50 percent chance fro 5 to8 will see
Continue to color me skeptical of our chances…I just am not fond of these sorts of setups locally. If this were Pennsylvania or western Maryland (or even NW Virginia), I might feel differently.
is it me or does the moisture in ark look like its moving this way
Is anyone else’s nose getting warm? Don’t deny it. The dreaded warm nose will rear its ugly head from Bristol up to C’burg. Looks like ROA gets more snow, despite being 1,000′ lower than NRV…….again!
Other John: If moisture running into banked cold air can do what it’s doing in my NE Arkansas homeland tonight on the 2nd day of spring, it can do it ANYWHERE!
That moisture will be moving generally this way for a bit, Henry, but is expected to become shunted southward and pass south of us Saturday. May be enough to cloud us up, though, and keep surface temps down a bit.
Oh there’s going to be a warm nose. It will push all the way through at some point, on the front side of the storm. Key to getting heavier amounts early Sunday will be getting walloped on the front end before it overtakes your location, wherever that may be. Just the nature of this beast. Same thing happening in Arkansas tonight. Warm nose pushes past northward in the morning, and all the snowy areas change to rain. Spring pushing against winter. Tis the season.
The NAM may or may not be accurately assessing this yet. But it’ll be there.
Kevin, I have a Clown Map question. Every time I’ve seen the North American version of the Clown map, like the one you recently linked, it shows most of Canada getting hammered with massive snows. Is Canada getting hammered with massive snows, or is Alan Huffman just making creative yellow, orange and white designs up north?
dont say that lets hope it stays cold
Newt: Actually, the Huffman maps are total accumulated snow on the ground. They work in this case because we won’t have any snow on the ground before this storm begins, so the total accumulated is a projection of that which will fall. The snow in Canada is that which has already fallen, a lot of it having been there for months.
Struck me this evening looking out over the backyard at 6:30 this evening how much sunlight was striking the clouds this late in the evening, yet it was bitter cold and with snow flurries. This kind of weather should be reserved for when it gets dark at 5pm!
I think all the plants and creatures are itching for spring but looks like we’ll have to wait a bit longer…
Yeah, Blacksburg Mike, I have been wondering the same thing, about the possibility that the warm nose might keep snowfall amounts down. We will see which way the trends go. So far from what little I can decipher, they are generally more bullish for snow. The next 36 to 48 hours for the model-watching will be key. I sure am in awe of the “teletubbies.” If I can find some time to concentrate on it, I may do another research venture into the AO daily levels going back in time. I know for a fact that AO levels below -5 are very rare …. just don’t know how rare.
Well that is true, Kevin. I guess I’m just sour on the Miller B-type systems because of how many times they don’t deliver much in this neck of the woods…but like I said a while back, every so often they do deliver. Perhaps this will add to the list of successful ones. But after this bout of cold, I’m ready for spring weather. The golf league starts up April 8th!
Hope, part of the AO ensemble shows some real “hope” for you. I didn’t mention it tonight, but I did last night, and there seems to be more evidence of it in today’s ensemble. The ensemble shows a real rise in the AO after 4-5 days, and quite a few models now show it really being a “rocket launch” all the way to +2 or +3. But it is in the extremely unreliable sector of the outlook, well more than a week away. IF it happens, I think things will warm up very abruptly within two days of reaching +2. I/we will know more about the likelihood of that happening about next Tuesday or so.
And I suppose that if the NAO is still very minus, that might negate quite a bit of the positive levels of AO. KM would know more about that.
Wow, Larry Cosgrove says a big no to snow. Has us at the edge of the thunderstorm area with a far north track.
http://www.examiner.com/article/weekend-weather-forecast-for-houston-texas-and-vicinity-friday-march-22-2013
So VT’s annual Ring Dance may escape the snow Saturday night but probably not the load-out and clean up on Sunday morning into early afternoon. Pull the Bean boots back out and toss a snow shovel in the car?
http://mag.ncep.noaa.gov/Image.php?model=gfs&area=namer¶m=850_temp_mslp_precip&cycle=00&image=gfs%2F00%2Fgfs_namer_078_850_temp_mslp_precip.gif
I just did a quick research about the number of days during the past four months when Roanoke’s high did not reach 40. Pretty amazing stuff. Number of days below 40 in December? …. NONE!!! In January, 6. In Feb: 4. So far this month including today? 5!!! We could very well end up with the most number of below 40 days in March!!
A quick nowcast. Midnight temp is 23* here. Am I going to make it to 19*? Probably not quite, but I bet it comes very close.
Yeah, NrVBrandon, just noticed that too. GFS has almost all the snow on the backside of the storm. NAM has almost all the snow on the front side of the storm. That puts about 18-24 hours difference between when there would be the most accumulation, getting into early Monday morning on the GFS.
GFS peaks at about 3-4 inches Roanoke area by Monday morning. Less to SW; more to NE.
http://raleighwx.americanwx.com/models/gfs/00zgfssnowdepth084.gif
Again, it does have more on the front side than I realized looking at the 850 maps, a little 2-3 inch bubble over Roanoke, Franklin and Bedford counties, basically.
http://raleighwx.americanwx.com/models/gfs/00zgfssnowdepth066.gif
Long way to go on this. I’m signing off for the night.
I am at 21*. Both Channels 7 & 13 have the precip starting about 10 or 11 AM on Sunday in ROA and Lynch. Probably about 8 or 9 AM for Wytheville. Channel 13 agrees with GFS …. back-loaded storm. They even came out with a first-look snowfall map. 1-3 inches for all of Roanoke County except for Catawba, and also 1-3 roughly east of the Blue Ridge. 3 to 6 inches for Catawba, Craig County, and everything S and SW of there.
Euro looks very much on track for a slushy Palm Sunday event. Some snow and sleet, maybe mixed with rain, then back to snow. This map for Sunday evening shows the inland low to our west, the new low forming off shore, and the banked cold air (blue colors) covering all of the region.
http://raleighwx.americanwx.com/models/euro/00zeuro850mbTSLPUS072.gif
NWS thinks it may begin as early 2 a.m. Sunday. Events with an overrunning element do seem to start earlier than modeled.
Daytime snow accumulation is a challenge to figure out with higher sun angle, longer sun hours and variable precipitation rates. Even with possibly a high in the 50s Saturday, the ground will be going into it colder than typical this time of year with this morning’s low temperatures and recent below-normal temperatures. Still, the ground absorbs more warmth this time of year than midwinter, even if the sun is behind clouds. Some sleet actually tends to help snow accumulation in these situations, as it’s denser ice that doesn’t melt as quickly. And of course if it snows really hard that tends to overcome the ground warmth. Starting the precip before or soon after sunrise could get it accumulating before the ground warmth builds much. Maybe an even more complicated part of the forecast than figuring out precipitation types.
WPC up to moderate risk of 4+ inches north of Roanoke, slight risk all the way to Va-NC line.
http://www.hpc.ncep.noaa.gov/wwd/day3_psnow_gt_04.gif
Slight risk of 8+ starts about where moderate risk of 4+ does, just north of Roanoke.
http://www.hpc.ncep.noaa.gov/wwd/day3_psnow_gt_08.gif
Probability of 1+ inch of snow up to 70+ percent Roanoke/New River valleys and northward. 50%+ for just about all of our region.
http://www.wpc.ncep.noaa.gov/pwpf_24hr/prb_24hsnow_ge01_2013032212f072.gif
Burrrrrr. We had 12.2 at the nearby Kings Weather Station.
Ohio prosecuter seeks death penalty in case against Punxsutawney groundhog Phil.
Read on friends: http://triblive.com/news/allegheny/3707083-74/phil-gmoser-spring#ixzz2OGDZBaag
Temps down to 11 this morning before dawn and no wind!!! Now bright sunshine and still no wind – hurray!
Kevin, if the GFS did a good job for Arkansas, does that mean we should go with it for our area this go around? Or can the Euro end up being correct for just us and another model correct for Northern VA?
Nick in the Ellett Valley, 1,575 ft – Happy Birthday to a fellow weather blogger!
It was down to a chilly 14 degrees with a thick 3D frost at my house this morning. Still not changing my mind on very little snow accumulation until something significant compells me to think differently. And I’m just still not sold on it yet, despite the WPC maps.
Carol: I wouldn’t make that jump. Models are often very situational in their accuracy — and in effect, it’s a different piece of energy leading to our potential snow than the one there. In Arkansas, the Euro was warmer and kept most of the snow in Missouri. Here, the Euro is actually a bit colder, though really there’s not that much difference synoptically between GFS/NAM/Euro, just some details that could be important locally.
Other John: A 70 percent chance of 1 inch is still a 30 percent chance of less than 1 inch. Basically, WPC is only going as high as a 2 in 3 chance of 1 inch of snow.
Don: I think Pennsylvania will call out the National Guard to protect their beloved and moneymaking rodent before letting an Ohio prosecutor determine his fate.
Happy Birthday to Doppler Carol and Nick
10.5F this morning, was surprised how cold it got!
Kevin since we are in a transition from winter to spring. Doesnt that make it hard for models to figure a winter storm out?
Wow, what happened to the GFS? I went from decent snow (18Z late yesterday) to just an inch with 06Z run this morning. The 00Z was halfway in between. However, the NAM is still holding with a significant accumulation (8+”?). Euro and Canadian running 4″ and 2-3″. That’s still pretty wide model divergence … even for this close.
Here’s a chart for the NAM.
http://weatherroanoke.com/namsnow.png
Wow. Of course that is total falling. But, even the “on the ground” amount runs 6-7″.
Not only did the GFS “dry up” alot, but the temp profile around 925 and 850 mb is not quite as cold (30 instead of 25) during the peak. This has happened before this winter, and the GFS was sharp in that it ended up being right, but lousy in that it waited until the last minute to peg it.
However, we’ve all learned to not peg on one or two runs this far out. Gosh, a couple of days ago, the GFS had 1/2″ at the most, and the Canadian and Euro had us at 9″. The next runs will help us. All above said, I’m not convinced the GFS it right (alone), yet. It may come back.
Winter and spring are lines we draw on calendars. The atmosphere is not as clear cut in its transitions. We saw in late January — mid-winter — how we could have a week where cold and warmth were juxtaposed against each other far more sharply than they will be this weekend. Don’t see any reason why models would have a harder time with a storm now than any other time when large jet stream amplifications are in play. (And often, it seems they actually do better in larger scale events with temperature and pressure contrasts than they do on smaller disturbances.)
Low of 23.8 here in Goodview, 23.5 in Jordantown. Amazingly if we get just one inch of snow out of this storm it will be our biggest storm this season. Now that I’ve said that, we’ll probably get one inch and that’s it
Kevin, in baseball terms, as to snow chances: what is the count/what bases are occupied/who is at bat/who is pitching? For example,best case scenario: 3-0/bases loaded/Matt Holliday batting/one of us pitching. Worst case: 0-2, nobody on/one of us batting/Aroldis Chapman pitching.
6Z GFS is definitely drier and warmer. The drier part may be even more critical than the warmer part — or rather it may be interconnected. Heavier precipitation through colder, drier air aloft will cool the column more, and would also lead to increased chances of accumulation at the surface. If this ends up being just light snow, even if it lasts a long time, it won’t stick much … and there’s a pretty decent chance if it’s light precipitation, it would be more rain and sleet than snow.
It’s an outlier for now in its dryness. Maybe on to something, maybe not.
I would presume at least a 25% discount on any model snowfall output, especially sub-3,000 elevations, owing to likely ground warmth and marginal surface temperatures with the sun angle/lateness of season, likely compaction, and probably a less than 10:1 snow liquid ratio. Any model that shows 8, for instance, I presume to be no more than 6.
I agree with Kevin, the weather can “ignore” the calendar, and the main principles still hold.
I do think they switch to the “spring equations” soon, though. That is, the models are adapted a little to account for more insolation and changes in dynamics resulting from very different thermal stacking of the atmosphere (thickness values being so different).
Point well taken, Kevin. I probably should have put this “snowdepth” map up instead or first.
http://weatherroanoke.com/namsnow2.png
clearly showing the mitigating effects you mention. Especially, as you say, this time of year.
Tom: I’ll play along, presuming Dec. 18-19, 2009 as the example of a grand slam.
Runners on first and second with 1 out. A .250 batter at the plate in the 8th spot on the lineup who hits few home runs. Danger of grounding into a double play and ending the inning. Or flying out (an inch or less) and leaving one more batter, the pitcher (NL) or a pinch hitter for late next week. Maybe gets a single and gets in 1 run (1-4 inches). Slight chance of double or triple driving in both runners (4-8 inches, widespread, not just higher elevations). Not much chance of a home run. Good but not great relief pitcher named Late Season is on the mound.
You must know I’m a Cardinals fan with your reference to Matt Holliday. (And saw him play for Salem early in 2000s.)
Think how cold we would be right now if this pattern set in in mid-January. I imagine we would be faced with pipe-bursting type cold.
I would add the batter is a pretty good contact hitter and probably won’t strike out, as in no snowflakes at all. Other John may disagree.
Wally: You’re probably right about the spring equations on the models. Insolation and solar angle are steadily changing astronomical variables that can be accounted for mathematically fairly easily compared to air masses in constant flux.
Nate: Yep, if it were 2 months ago, it could be below zero with this blocking pattern. And we wouldn’t be wondering about snow vs. rain vs. sleet for Sunday — the bigger worry for snow lovers might be if the entire system would be suppressed and it would snow in Savannah and not here.
Hey Kevin if this is looking like March 5-6 part Deux can we have it just miss and go elsewhere? Last year out first weekend on baseball got rained out now this year it looks like it might get snowed out. I just want Spring!
I’ll wait to say anything for what i think we get officially as far as accumulation is concerned, because i have a feeling the 12z runs will offer us up a decent snow, though not a lot. My first guess on accumulations is 1-3 for NRV, 3-6 for central and north Shenandoah valley, Rain/mix East and south of Lynchburg and west and south of the NRV, and Roanoke right in the middle with about 2-3 inches with either accumulation amount varying due to elevation and location within the roanoke valley.
Kevin, I think Late Season has a good breaking ball and sinker that could do the trick…but if he hangs the breaker over the plate too much, I could see a solid rip into the gap in right-center for a 2-run stand-up double.
Baseball metaphors in weather…I love it
How’s Charlottesville looking Sunday morning/afternoon. They’re still playing basketball up there and were so lucky to get an 11am tip.
Thanks Kevin. Excellent analogy. Correct on the Cardinals. As a Reds fan, I also used Holliday in the example because he seems to hit .750 WRISP against the Reds. Holliday must have been a man against boys in Salem.
Well, I’m going to go on to the grocery store and get the “normal” stuff, just in case I score a snow day on Monday LOL The kids at school and my own are starting to act all crazy, similar to what we see before a big storm comes through BUT also what we see when it’s time for Spring Break! I can at least guarantee that spring break is coming
Kevin, do you have any Missouri/Arkansas snow totals from yesterday?
I don’t think anyone’s getting 20 inches out of it like I-64 corridor and north did on March 5-6, so I’m not going to honor it as Part Deux. Would be hard to steer it where it doesn’t do anything at all, even rain.
Too me, it feels like EVERY OTHER winter weather system we’ve dealt with since Dec. 26 — murky rain/sleet/snow mish-mesh. Jan. 25 was the 1 and only unambiguous non-upslope snow situation all winter, all 1-2 inches of it.
Baseball analogies just mean lots of folks are ready for real spring to begin.
Rick; Biggest snow total I’ve seen is 8.5 inches at West Plains in south-central Missouri, just above the Arkansas border. South-central Mo/north-central Ark. was the bullseye, with lots of 5-8 inch reports. 3-5 inches in much of NE Arkansas. Already melting fast!
New NAM (12Z) is a wet snow wallop:
http://raleighwx.americanwx.com/models/nam/12znamsnow_SE060.gif
http://raleighwx.americanwx.com/models/nam/12znamsnow_NE060.gif
(stuff in Canada is pre-existing snow cover)
Showing 9+ for Roanoke/NRV, mostly front end stuff Sunday and 7+ most of region.
NAM usually leans a little on the wet side. But if it verified, even with my 25% late season discount, would be 5-7 inches.
Not buying this yet.
The NAM has been seriously wet this year…I remember it threw out some 73″ amounts for the storm that hit Boston.
The new NAM brings in heavy precipitation rates, which would be a big key both to getting more snow quickly rather than rain/sleet and to accumulation on the ground overcoming sun angle/residual warmth issues. Here’s the simulated radar for early Sunday afternoon.
http://mag.ncep.noaa.gov//Image.php?model=nam&area=namer¶m=sim_radar&cycle=12&image=nam%2F12%2Fnam_namer_054_sim_radar.gif
GFS has been trending drier. We’ll see what 12Z GFS looks like in a little bit.
I may update with new blog entry at midday.
WOW! I’m good with 5-7 inches. I would have really happy kids if that verified!
Looks like March Madness extends to this weekend’s weather too…glad we have a solid supply of firewood to keep burning! But, I need to split more, we’ve gone through half of the ready-to-burn rack after having to wait a couple extra months to get the firewood dry enough to actually burn this winter. Never buy a load of firewood right after a heavy rainstorm!
So your high avg ground ball hitter just turned to a power hitter with a lower overall avg.
The NAM has been known to be juiced. Awaiting results of the drug test on this batter.
If the NAM is on the right track, there’s not much left for us on the backside of this storm. It’s just about all on the front end. Snows like crazy during the day, done by late afternoon. Or if it’s a couple degrees warmer aloft, cold rain all day.
On that part, I’m buying it. I think it’s about the front side, not the back, for Roanoke/NRV and southwest. Been my hunch all along. If it ain’t white by 2 p.m Sunday, it ain’t happening.
Blacksburg NWS has the biggiest block of precipitation (.20) between 8am and 2pm in my neck of the woods (Pulaski). And they are thinking it’s going to be rain.
Only if we could get a late start say 6pm Sunday night. Yes I’m being selfish and want all the snow, and all the sports I can get this weekend. Kevin I did read that the NAM was named in the Mitchell report so you might have something there.
i hope we do get 1oinches we aint got nothing all winter in bedrock
Newman, are you looking at the digital graphical forecast? Based on the GFS, it has only 1 1/2″ for Roanoke, and now real snow SW of Christiansburg. I have doubts about the veracity of anything based solely on the GFS for the moment.
BTW – to be more precise on something I said earlier. The NWS does change the models to the “warm season” equations, but only for the MOS output from GFS and NAM (called MAV and MET). It changes Apr. 1, and goes back about Oct. 1 (if I remember right).
Typo – “NO real snow SW of Christiansburg” – sorry
I wouldn’t put all my eggs in the NAM either. It’ll be fun to see how it all pans out.
About 1-3 inches in Roanoke/NRV on 12Z GFS — still warmer and drier than NAM.
http://raleighwx.americanwx.com/models/gfs/12zgfssnowdepth072.gif
Also worth noting that the NAM drags few a few rain/snow showers into part of SW Virginia tomorrow morning.
http://mag.ncep.noaa.gov//Image.php?model=nam&area=namer¶m=sim_radar&cycle=12&image=nam%2F12%2Fnam_namer_024_sim_radar.gif
http://mag.ncep.noaa.gov//Image.php?model=nam&area=namer¶m=sim_radar&cycle=12&image=nam%2F12%2Fnam_namer_027_sim_radar.gif
Maybe not a huge accumulation threat — above freezing, dry air aloft — but could spread some clouds that hold temperatures below expected highs in low-mid 50s.
Looking at the new 12Z GFS rolling out now, it does look like the GFS is upping the ante some over it’s 06Z run. I can only see through 2 pm Sunday (3-4″ to that point).
Still wondering how much sleet will really cut into the snow totals. Don’t want it to be a sleetfest.
New Navy model (NAVGEM) has us pretty cold, though (another slice of input).
I suppose we wait for the 12z Euro run and see what it has to say.
So what we have right now is:
12z NAM 6-8 inches
12z GFS 1-3 inches
Euro: ?-? inches
Im thinking Euro will either take the GFS side or will provide a median between GFS and NAM of around 3-4 inches.
I’m becoming more and more convinced that Roanoke will pull out a solid 3″ of snow out of this system. I’d love more but we need a big push of robust moisture and cold temps such as what is being depicted on the NAM.
Just posted a new entry.
I will be sporadic on the blog this afternoon and evening … probably will not put a fresh post up again until Saturday morning.