UPDATE 11:50 PM, 12/5: Rainfall amounts (maybe snow chances?) on the uptick this week as cold front slows down
UPDATE 11:50 AM, 12/5: Some model guidance this morning suggests the possibility that the low-pressure system Wednesday and early Thursday may track far enough eastward to pull cold air into the region and throw back enough moisture for a shot at some snow. We’re discussing it on the blog from Comment 27 (10:34 a.m.) onward below. More on this later. END UPDATE
UPDATE 10:30 PM, 12/4: No major changes to below. Rainfall projections around 1.25 inches on Sunday night for most of Southwest Virginia. Some showers could move into the area as early as overnight Monday or very early Tuesday morning, but it appears bulk of rain will be Tuesday night and Wednesday. END UPDATE
One recent early December tradition in Southwest Virginia weather will not be renewed this time around. In 6 of the last 9 winters and 5 of the last 9 at Roanoke, there has been measurable snow on Dec. 5. In both 2002 and 2003, it was the second day of winter storms that started on Dec. 4 leaving widespread 6-12 inch snows (capped by sleet and glaze ice) on the region. Lighter snow in the 1 to 3 inch range fell on Dec. 5, 2005, and lighter still with about a half-inch at both Blacksburg and Roanoke in 2007. Dec. 5, 2009, brought an elevation-dependent wet snow that left nearly 4 inches at Blacksburg but only a trace of snow at Roanoke Regional Airport, more in outlying areas and higher elevations of the Roanoke Valley. And a year ago today on Dec. 5, 2009, an Alberta clipper brought 2.6 inches to Blacksburg. 1.4 inches to Roanoke and widespread 1-3 inch amounts with locally up to 4 inches. With dry weather and highs in the 50s on Sunday (Dec. 4), and some highs maybe clipping 60 on Monday, we won’t be seeing snow on Dec. 5 this time around.
The run-up to this coming week’s rain system looks a lot like about the last two or three that have come down the pike, with the heaviest amounts forecasted in the Tennessee and Ohio river valleys west of us, but the projected heavier amounts slowly encroaching into western Virginia during successive forecasts. The Hydrometeorological Prediction Center’s 5-day rainfall projection map on Saturday night has begun putting Southwest Virginia in the purple colors for rainfall amounts topping 1.5 inches (2 inches along/west of Blue Ridge). Two factors are driving up the projected rainfall totals. The first is indications on all the major forecast models of the cold front slowing down, even stalling, as it advances eastward. A couple of days ago this was being thought of as a Monday night-Tuesday rain; now it looks to be a Tuesday night-Wednesday rain, if not stretching into Thursday a bit. The second is the potential for multiple waves of low-pressure to ride up that front, including one that could come roughly up the Appalachian Mountains. Any waves of low-pressure that far east would not only contribute to the front stalling, but could pull additional moisture out of the Gulf of Mexico and/or Atlantic against the front and the mountains. The exact rainfall amounts, of course, are subject to some up-and-down movement in predictions, just like they were last week. Once the front goes by, colder weather will move in late in the week, and there’ll probably be some snow showers blowing over the mountains about Thursday or so, especially if there is a low to pull in even more cold northwest winds behind it. It’s doubtful the cold air will be able to catch up with the moisture enough for more widespread snow. Next weekend looks pretty cold for the region.
December 3, 2011 - 10:53 PM
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Tonight’s 0Z GFS is a little interesting. It has a low forming in Georgia and moving just inland up the coast late Wednesday. That pulls some cold air into the back side of the rain shield and you know what happens.
The only way I could see a real snowfall developing out of this week’s storm would be to bring a low up the front AFTER it has passed through our region so that the low moves roughly up the coast. Possible, still not likely.
Bulletin from the Nat’l Weather Service … Flash flood warning for SW Virginia right now, with the heaviest flooding in Blacksburg. But not from rain, but tears from Hokie fans. Exactly one week after their best game of the season and perhaps in several years, poor VT had their worst half perhaps in the Frank Beamer era and got routed in the ACC title game, 38-10.
We need a “snow” event (or ice potential) to pop up on the horizon so the number of comments can increase on this blog. Looks like we need to bypass 54.
Not what one would call a warm day in Mendota but my sheets are frying on the clothesline. This is definitely not the kind of weather for lots of comments! I agree with Carol…it will take a nice snow forecast to get our comments past 54.
Whoops. It is not warm enough for the sheets to fry. They are drying–not frying!
Someone mentioned the 12z euro brings some light snow in our area. 12z GFS has heavier snow not too far north of the area (judging by the snowfall map).
Since things are slow here today, I will toss in something I considered interesting that had nada to do with weather. Nancy and I went out for a late breakfast, and within 2 feet of Brambleton Avenue at Fishburn Park a red-tailed hawk was having his or her own breakfast. Know (or care?) what I call crows, hawks, turkey vultures, etc.? “Nature’s clean-up crew.” They help dispose of road-kill, which we have a lot more of down here than what we used to see near metro Washington, DC, of course.
I just went to wunderground’s website to see what the GFS is showing for D-Day, and they are showing a bright pink area (rain?) just to our east at 9 AM, and a blue area (snow?) in northern Virginia between Richmond and DC and a bit east of there for noon. But for the same timeframe on yesterday’s runs, they were showing the entire eastern 1/3rd of USA to be dry. And tomorrow’s runs (or if not those, then Tuesday’s) will show something different for 12-12. And condolences to those of you who chose Dec. 4-5-6 for first inch of snow in the snowfall contest. I will probably be joining you all next Monday night.
I just looked at what the noon GFS run is showing for this coming Thursday, and very unlike what WDBJ7 is forecasting, GFS is predicting a day with lots of precip!! Possibly snow? There, I typed the magic word. C’mon blog readers …. make some comments!!
I just checked the NWS forecast for Roanoke City, and they are forecasting the same as Channel 7 (big surprise there, right? Not!). Sunny on Thursday, and quite a bit cooler, but actually seasonal. Normal high for ROA today is 51, so by Thursday it will be 50, and NWS is predicting 48.
Thought I’d help with the numbers. Just looked at what I(and my husband) had guessed for the first snow dates, and we are both out of the running. Hope springs eternal, however. Come on Kevin, snowdance…we’ll all join in!
I just had that CAPTCHA Code thing happened to me and I had a good comment.. darn.
Oh well, here is the gist of what I wrote:
Since it seems to be a little slow (I think us snowlovers are sad and depressed), let me ask a question that I’m sure has been answered before: why have the average lows been a lot higher than normal? Does this relate to climate change’s impact on the rate of evaporation of water, thereby increasing cloud cover and therefore keeping temperatures warmer at night? Any takers? I’m not trying to get into a climate change debate (DISCLAIMER: I personally believe in the science behind it), but what might be causing this? The average highs don’t seem to have changed too much, judging from the new “normals” released by NOAA.
Uh Oh Henry M. at Inaccuweather is jumping on the Negative NAO train! He said mid month looks like the NAO might go negative. If he jumps on it must be a really good chance of happening! Let winter finally begin!
OK – let’s get in the game – SNOW!! SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!SNOW!!
By far the best snows I remember when I was growing up in Roanoke were the ones that came unexpected and not predicted. It was when you went to bed and woke up with snow falling. Not many surprises anymore due to the better forcasting and all these bloggers who tell us what is coming. I enjoy the blogs and forecasts but would love one of those surprises from days gone by. Sometimes life is just too predictable.
Keeping thinking snow, snow and more snow.
Travis: There is a DEFINITE trend toward warmer low temperatures, especially in summer. I’ve read material noting it on a larger national/regional scale, but I can only speak to local readings myself. Separating how much of that is urban heat island warming (Roanoke Regional Airport surrounded by commercial development in last 25 years, Blacskburg’s thermometer being in research park) and how much is due to larger factors, be it natural oscillations or man-contributed global warming, is the trick.
Michael: True we have fewer TOTAL surprises these days. Satellites and radar make it hard for a system to just totally sneak up on us. Winter weather surprises these days usually would be getting more snow when it’s supposed to be mix (Dec. 5, 2004, fits in that category), or heavy snow developing in expected light snow situation or snow developing out of would-be rain. Surprises the other way — less snow than expected, earlier change to sleet/ice/rain than expected — seem to be more common.
New HPC 5-day rainfall map: About 1.25 across the region, mostly with low-pressure impulse moving through Wednesday. http://www.hpc.ncep.noaa.gov/qpf/p120i00.gif
sorry folks,
I was over at Andy Bitter’s VT blog making my peace with Kirk Herbstreit…NOT! So the BCS is a mess like the models trying to figure out our first snow.
So Ok, I’ve been a little busy today and haven’t time to look at the models. What’s this about snow? Be right back.
Yeah talk about something coming out of nowhere …VT to Sugar Bowl was like the sports equivalent of getting 10 inches of partly cloudy, or an all-day rain during a winter storm warning, depending on your opinion of the Hokies.
back to the weather Sports Fans
Professor Quags says no snow for VA this week except for the mountains above 3000′ that get the NW flow upslope snow showers. GFS is over playing this week’s event and it is still a little too warm.
Mr. Griggs and et al checking out In-Accu-Weather. Henry M. is still drinking too much Egg Nog. Per the Euro, NAO IS NOT GOING NEGATIVE, neutral maybe but nothing significantly in the – side. It will be less positive though. He is looking at the 12Z GFS run Sunday PM and it shows -NAO returning December 19. It also shows huge storm for midwest but no snow for VA or Mid Atlantic. Again GFS is useless this far out.
back to normal programming
What got into the water today? Mr. French has an ally in William (welcome to the blog, W). Those two guys are going nutso about snow with nary a snowstorm in sight. Even my 12-12 prediction for a snowstorm is in big trouble, because the TWC 10-day forecast shows dry weather starting Friday right through a week from Tuesday. High here in ROA of 51 for 12-12. Of course the world could end before then, things can change so rapidly. But the polar vortex seems to be unable to get a negative NAO (nor a negative AO, either) going for a while longer. Kevin, how about posting another one of those maps with a view of the northern latitudes again either tomorrow or Tuesday? And even if we do get a neg NAO or neg AO going, that is no guarantee of a decent-sized snowstorm here, just a very strong likelihood of colder than normal weather.
While we are all waiting for our first significant snow here west of the beautiful blue ridge, the folks in the urban swamp that is Northern Virginia, are still waiting on their first frost. Reagan National has not gone below freezing since March 28th!
I know this is not the sports blog…the BCS has been a mess for a long time. This sort of makes up for the Hokies getting shoved out of the Fiesta Bowl by Notre Dame about 10 years ago (and Notre Dame lost). This overcast Monday is not just a great day to be a Hokie, it’s an AWESOME day!!
GFS continues to flirt with bringing colder air far enough east for some snow in the region late Wednesday into Thursday. Suspect if it happens it would primarily be higher elevations and/or west of I-81.
We CAN get a significant snowfall here without negative NAO or AO. But those 2 factors greatly ratchet up the odds of lasting cold, which increases odds for having cold air for snow. Both indexes are highly positive right now, the AO extraordinarily so. That correlates to lower pressure over the pole keeping the Arctic air pulled in tighter to the Arctic rather than venturing south, and low pressure over Greenland keeping the jet stream flow over the US more west to east rather than crinkling southward.
http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao.mrf.gif
http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/nao.mrf.gif
Here’s the 500 mb pattern of temperatures as of Saturday evening, as depicted on the Euro Model. You can see the colder air bottled up nearer the pole, and mostly the other side of it.
http://blogs.roanoke.com/weatherjournal/files/2011/12/00zeuro500mb1205.gif
Talking about snow, Euro model for Wednesday evening now puts low-pressure system on VERY favorable track for snow throughout our region:
http://blogs.roanoke.com/weatherjournal/files/2011/12/00zeuro850mb72hr1205.gif
Note the low at the favored location off Hatteras and the colder air pulled behind it in the blue colors into western Virginia.
We’ll see if that pulls more inland with later runs. If Euro is on to something with Sunday night run, snow potential would ratchet upward quite a bit.
12z NAM continues to show 1-2 inches for north and west of Roanoke.
Hey, I’ll take it if that’s the case. Still a long way to go though.
Kevin-yes, I see some clown maps coming out painting some white stuff here in Southwest Va.. I don’t know if I am buying in quite yet. Is there a place that shows what ground temperatures are around the region? Does VDOT report that? It is going to snow awfully hard to get the 3-6″ of accumulation that Bastardi is calling for…the ground is just too warm yet.
On the other hand it could be a horrible mess if it is heavy wet snow that then freezes solid…yech.
Snow? Kevin, you said SNOW!!!!! As a school employee snow is always a welcome sight!
I’m a lurker during the fall/spring/summer months, but I try to be a little more active when you start talking about snow
We’ve had some pretty cold mornings and not a lot of 65-plus temps in the afternoons, so I don’t think ground temps would not absolutely be prohibitive. Still, if it snows, it would likely be a wet snow sticking to grass and trees long before it collects on bare ground or streets. Track of the low is the critical issue. We have a couple of days to pin that down.
I would put the snow chances at at least 50 percent. GFS and Euro are in agreement of a s/w digging pretty far South enough to get the NRV Highlands in on some very good heavy wet snows Wednesday – Thursday…. Like Tech’s bowl selection this is much a surprise…
And I will add…Our best snows always seem to come to me, when they sneak up on us, like this, within the 60-80 hour range.
SNOW??? Here we go again. The comments should start increasing now. Shanon (#30)welcome to the blog. If you are a snow lover you are automatically a member of the TWLS – Those/Teachers Who Love Snow.
Professor/Captain – care to weigh in on the comments about the possibility of snow? Still thinking no snow this week?
It was 43 F up here on the ridge this morning at 6:30 am. The warmest we have had in several days.
12z GFS would be heavy snow farther east than just NRV.
Let me clarify a comment above with a double negative … I do not think ground temps would be so warm that it would totally prohibit accumulation.
12Z GEFS
http://i44.tinypic.com/34pc6zn.gif%5B/IMG
Would love to see a little snow, even just enough to cover the ground here on lake. It may help get in the Christmas spirit . MANY bLESSINGS!
I think some hacker organization or foreign power has gotten into the computer that does the BCS bowl selection calculations. And now they’re monkeying around with the weather forecast models!
Kevin – you may want to add the New Orleans current weather conditions to your list on the right side.
Dop Carol – what do you use to measure your temps?
Euro at 66hr.
https://fbcdn-sphotos-a.akamaihd.net/hphotos-ak-ash4/376008_169789203118838_100002632795360_282147_2124060311_n.jpg
Thank you Doppler Carol for the Welcome! I’m sure Mr. Griggs will try to win me over to the snow haters
I grew up in deep SWVA, so I LOVE snow. I will not pretend to know anything about weather patterns and such, but I was in Saltville yesterday for a family get together and the clouds looked like “snow clouds” to me.
HokieTrax – We have the Honeywell Professional Weather Station but my temperature component no longer works so we bought a LaCrosse Outdoor/Indoor thermometer. It sends the temperature into the house where the digital display is set up. The thermometer is in a covered spot but not completely shaded. I do not go by its temps on sunny days but on cloudy days or before the sun hits it, I feel the temps are fairly accurate. I miss the Honeywell thermometer – anyone know where I could find just that part?
Right now in the yard it is 53.1 F.
Shanon – glad to have you in the TWLS. Yes, Doug will try to get you to go over to the “dark side”. Don’t let him.
So the Euro is showing snow in Roanoke, and Richmond- but hardly any in Central Virginia.. that’s going to be very strange it if actually happens.
If we can garner that inch of snow this week, I guess I’ll only be off by a few days in the contest. Hopefully this also might allow Snowshoe to open this Friday as currently scheduled. I’m off next week so I’m hoping they’ll have some slopes ready!
btw HokieTrax, neither Notre Dame nor VT (I’m a HUGE fan of both) were beating Oregon St in the Fiesta Bowl that year. VT would not have stopped Chad Johnson (as they weren’t able to stop Calvin Johnson or Larry Fitzgerald).
Sorry for the sports comments Kevin
WOW @ 60hr 18Z NAM!
http://mag.ncep.noaa.gov/GemPakTier/MagGemPakImages/nam/20111205/18/nam_namer_060_850_temp_mslp_precip.gif
Roanoke is within slight risk (10%) of 4 inches, 3 days out:
http://www.hpc.ncep.noaa.gov/wwd/day3_psnow_gt_04.gif
I see where NOAA introduced the possibility of snow in our forcast for Wednesday night. Just a rain/snow mix at this point.
In an effort to keep from angering the Snow Gods (and my wife), I will not take the snowblower out of the shed and put it in the garage until we actually have snow on the ground this year. Last year I made both extremely upset when I moved it from the shed to the garage in late November. I think I used it once and that wasn’t really necessary but it was fun.
DT has joined in with the storm idea and is giving first guess map around 5 pm. He said most snow will fall in Shenandoah Valley just north of Charlottesville, which is us here in Greene (Yahoo) and on into central MD. Hope his guess is correct!
Just goes to show that I can detect the S word from far away!! I haven’t checked in for what seems like weeks and decided to today…but of course, the word SNOW was mentioned. I can only hope, right? I’ll be watching =)
Thanks Roa10 for posting the HPC snow risk map. Saw it but not where I can easily post a link right now. Will be updating blog this evening.
@Alex
18z GFS is too far west for any good snows in our area, need the low about 50 miles further se, and we would be sitting pretty. Think this is a good possibility. Climatology wise, a low usually doesn’t take the more inland track suggested. Would put Axis of Heavy snow in a weird line from Charleston, WV through Lehigh Valley up through NE.
******BREAKING WEATHER NEWS******SURPRISE SNOW COMING WEDNESDAY NIGHT TO THURSDAY MORNING FOR WESTERN VA!!!!
ACTION NEWS 99 WEATHER ALERT…Now we turn the broadcast over to our distinguished Perverted Prognosticator, Professor Glen Quagmire, senior fellow at the Griggs Meteorological Center of Western Virginia, Professor Quagmire…
Good Afternoon Ladies & Gents!
This afternoon’s model data is coming together for SNOW possible from late Wednesday evening thru Thursday morning for much of Eastern WV/Western VA/Northern VA Piedmont/Western & Central MD. This will be a rain changing over to SNOW event starting as early as Wednesday Noon from the NC Mountains (Boone) spreading north & east.
Monday PM 12Z Euro from PSU
http://www.meteo.psu.edu/~gadomski/ECMWF_12z/ecmwfloop.html
Monday PM 12Z GFS from PSU at hours 60, 66, 72:
http://www.meteo.psu.edu/~gadomski/CMC_12z/cmc60.html
http://www.meteo.psu.edu/~gadomski/CMC_12z/cmc66.html
http://www.meteo.psu.edu/~gadomski/CMC_12z/cmc72.html
Even the NAM is in the game at hour 66:
http://www.meteo.psu.edu/~gadomski/WRF_12z/wrf66.html
Right now as it stands…Look for the SNOW best coverage if the models come true are west of Route 29 corridor Lynchburg to Manassas, North of US 460 corridor from Appomattox west, I-81 corridor from Wytheville north to Hagerstown including all of the Shenandoah, New River & Roanoke Valleys. East of route 29 will see all rain mixing with or possibly changing to SNOW at the end.
Please consider that air & ground temps have been warm so this could be a tricky accumulation forecast to pinpoint. I’ll go into more detail later on as to how much SNOW could fall in the Old Dominion. I am going out on a limb here…EXPECT WINTER STORM WATCHES TO BE POSTED BY TUESDAY EVENING BY THE NWS FOR THIS EVENT ALONG & WEST OF THE BLUE RIDGE INCLUDING THE VALLEYS.
12Z Euro & 12Z GFS put surface freezing line (32 degrees) right along I-81 corridor north to central MD well west of I-95 corridor. North of Philadelphia may be a more serious situation.
Will update after dinner…
Dave Tolleris first guess map out shortly.
@alex on that note, 18z GFS is further SE than noon runs, not by much BUT enough to get the WHOLE area in on good snows. This trend is your friend.
18z nam snowfall map just updated, shows around 2 inches for our area. More north and west:
http://wxcaster.com/gis-snow-overlays2.php3?STATIONID=FCX
Glen, if that pilot thing doesn’t work out, you can land a cheezy nightly weatherman job easy. Add a bad toupee and you got it in the bag, man.
Hope your forecast works out for us but we are about a mile east of Rt 29 (and maybe a mile south of Rt 33) so hopefully enough cold air will move just east of 29.
DT first guess map:
http://1664596.sites.myregisteredsite.com/meteorology/1stguess.jpg
I’m not buying it.
I don’t see the rain/snow line getting below 2500 feet.
Sorry guys.
Dave Tolleris’ 3-inch line goes right smack through Roanoke.
There’s no doubt that higher elevations will see the snow first, and therefore, likely, more of it. However, it may well be that by the time the storm is at its peak, it will be less of an up-down thing this time and more of an east-west thing. Where will that rain snow line set up? I-81? Lynchburg to Martinsville? Richmond to Raleigh? And how long will the snow last at lower elevations once it changes over? Tough questions to answer right now.
Finally, an ‘ole fashioned Virginia snow track, that puts the bulk of the snow on the I-81 corridor. A classic case of where it is more critical to be west than north(i.e. Galax, near the NC line, gets more snow than the D.C area, which will be too far east). When will the NWS and local mets catch on?
If Dave’s thinking holds, then who ever picked December 7 and/or 8 for the first 1″ snowfall is winner winner chicken dinner. I’m a week late as I picked December 14.
John…lol! Maybe I’ll do the Goatee thing that Cantore is working on.
Zach…GFS & NAM should trend a little more east in the couple of runs & put I-81 in the sweet spot.
Brandon…are you thinking that doughnut hole is going to make a cameo appearance again keep the snow away? I’m in the tune of thinking 2-4″ in the valleys with 3-5″+ above 2500′
Betsy…did not forget about you either. I reviewed your 06Z GFS observation from the weekend. Now the Medium Range models are beginning to hint @ a possible pattern change after December 20 with the possibilty of a significant winter weather event hitting the eastern US around December 21-22. This is your former December 19 Ice event. 12Z GFS for now shows an Appalachian Runner. Euro weekly is beginning to latch on to this as well. Still a ways out and even this one now bears watching.
Quagmire: I actually picked December 8th in the snowfall contest. I’d be ecstatic if this happened.
But what I’ve learned is that nine and a half times out of ten, if the cold air isn’t locked in place BEFORE the storm gets here, no dice. This is why I’m skeptical.
… and without a doubt what Brandon mentions is the biggest issue in all this. By “here” I’m thinking you mean the floor of the Roanoke Valley.
Boy, were my ears burning this afternoon!!! Now I am on the blog, and I find out why. Welcome back to the blog, Shanon. You can be a Snow Lover, Snow Liker, or Snow Hater, it makes no diff. to me. We’re all adults here …. I think. Seriously. So those of you making predictions that I would try to persuade her to join the SHC (Shanon, that’s the “Snow Hater Club,” FYI) were wrong.
Brandon, I am incredibly impressed by your comments!! Seriously. Doesn’t mean you will be correct, but I notice a tremendous change from the Brandon of late 2009. I will make no predictions about what happens on Wed. night/early Thursday (Sam Oakey, please take note … I am trying to follow my own rules). However, when it comes to seeing anything more than a dusting on grassy and metal surfaces at “O-Dark-Thirty” Thursday, I will revert to one of my favorite acronyms. IWBIWISI. Translation for new folks to the blog: “I Will Believe It When I See It.” May you have good luck with this threat, Snow Lovers.