There’s a lot more cool air where this came from
Temperatures are slowly moderating in Southwest Virginia after this past weekend’s cold front. Roanoke topped 80 (high of 81) and Blacksburg almost did (79) on Wednesday, after morning lows that were in most places about 5 degrees warmer than Tuesday morning’s chill. Lows may again be a bit warmer on Thursday and Friday, more 50s than 40s across the region, with highs similar to what they were today, if not creeping another degree or two upward on one or both days. But long term, there is still a lot of cool air in the tank, and strong indications that the weather pattern will set up to pour that tank of Canadian chill right into the central and eastern U.S. over the next couple of weeks. It will probably about another week until we get the next major installment of cool air, though a weak cold front over the weekend and early next week may somewhat reinforce the general temperature regime we have now. But, after that, areas of high pressure building over Greenland and the western United States are expected to funnel a shot or two of genuinely cold air from the Canadian tundra 
southward. The 10-day European model picks up on this pattern well — it’s what would be a classic pattern in midwinter for Arctic air shots and possibly a winter storm or two. You can see the circled blue H’s over Greenland at the top of the screen and farther south over the north Atlantic — this signals the “negative phase” of the North Atlantic Oscillation, which will have increasing impact the deeper we get into fall in bringing cold air southward from the North Pole through Canada into the U.S. The blue/green colors show lower atmospheric heights building southward, with cold air filling in, and several low-pressure centers over Canada and the Great Lakes. Forecast models are in close agreement on the general nature of this pattern, though not all the specifics. This pattern will continue to bring occasional shots of cold air southward — such as this one (blue colors) depicted by the Euro moving into the U.S. on Sept. 22. If this all transpires as it looks now, I would not at all be surprised to see the first lake effect snow develop along some of the Great Lakes (probably the more northern parts) during the next two weeks, and probably more widespread 30s in our region at some point rather than just Burkes Garden’s lonely 36 on Tuesday. Exact low temperatures are of course impossible to forecast this far in advance, but suffice it to say that it’s unlikely that this week’s cool mornings will be the coldest of the month . But then, it’s rare in any September for the first 10 days to be the coolest.
For those looking for rain, the front stubbornly edging in over the weekend and early next week may be able to squeeze out some moisture, but it doesn’t look like there will be a lot to work with. A storm system may develop in the central U.S. and head toward the Great Lakes, again not a great storm path for rainfall in our neck of the woods. We should keep an eye out though for possible storm systems spinning farther south with this pattern that could bring more widespread rain just before one of the new cold air intrusions, but there’s nothing firm on the horizon just yet.
September 12, 2012 - 10:58 PM
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A power surge on 9/10 around 11:30 PM in the Hokieburg area has fried the HVAC systems in several buildings on campus along with electronic equipment such as computers that were not protected with surge protectors. My building lost the AC…we have all our computers plugged into to surge protectors fortunately. At least it is not too hot or humid outdoors and we do actually have some windows we can open but modern buildings are simply not designed to not have air handling. So it’s been uncomfortable, especially on the sunny side. So bring on that Canadian air!
Charlotte meteorologist Brad Panovich posted this on Twitter — long-range GFS showing measurable snow in western Pennslyvania and northern fringe of West Virginia on Sept. 25.
https://www.facebook.com/photo.php?pid=1006632&l=e050ded13c&id=162655917140206
Probably won’t happen, but interesting …
55* here at home, both when I awakened at 4:20 and now. Gorgeous pre-dawn, with a skinny crescent moon over Mill Mntn. from my point-of-view. The totally clear pre-dawn skies this week remind me of some of the opening scenes from the movie 2001: A Space Odyssey.
43 up here on the ridge this morning with low lying clouds/fog but now the sun is up and starting to burn it off.
Doug Griggs called me this morning from Burkes Garden. When he arrived the temp was 43 and VERY FOGGY! He said the General Store is now closed effective 12-31-11. Very sad! He could not see anything basically b/c the fog was so dense. He called me again close to 9am to say that he had hiked to the rim of the Appalachian Trail and it was GORGEOUS! He said it was completely clear along the rim, but that fog was sitting down on Burkes Garden. The temp on the rim was 50.
I hope he can get some good pics to share! Even though I grew up probably no more than 45 minutes away from Burkes Garden, I have never gone. I do remember my dad going to the Cattle auctions in Tazwell and always bringing home fresh baked Amish bread though! Good memories!
GFS model looking a little wetter next week ahead of the cold air shot, with a low developing more to the south. Still not seeing a huge rainstorm for our immediate area, but maybe some 1/2 – 1 inch type amounts, which I know many of you would welcome. We’ll see if this matures some more on later model runs.
Bummer on the store closing Doug. I always liked eating there on every visit. Going in mid October was always a treat when lots of outta staters came to the store, gassed up, ate up and enjoyed the Garden. Lots of motorcycle rider tourists would stop. Hope you had fun anyway.
Hokie Trax…we noticed a similar surging of our power in Pulaski County around the same time, two short bursts of fluctuating power for about 1-2 seconds each. Very odd, our lights flickered and buzzed and quite a bit of the electronics made some weird racket, but everything of value was in surge strips, that didn’t trip, and nothing seems to be out of whack. Not long after, a couple folks I follow on Twitter mentioned they experienced what you described in the ‘Burg…very peculiar. We’re on AEP…
Incredibly foggy again this morning until crossing Price Mountain and dropping into C’burg.
Kevin: Though I love cold weather and snow, all of this talk about cold weather at the end of this month has me a little worried. We are going to the beach (South Carolina) for the last week of this month. Do I need to pack my long underwear?
Kevin, when is the first typical “Killing Frost” in Roanoke? I’m thinking of putting out a few cooler weather veggies in the garden and want to see if I’m too close on the time frame already or not.
My computer had rebooted overnight, so either there was a power surge or some automatic updates that rebooted it. We have had some odd problems with microsoft exchange here at work today, but I don’t know if it is an internal problem or something else.
Kevin, several times you have pointed out patterns that during winter months could result in the potential for snow. I understand the jet stream dipping south sets up cold and if the southern stream brings in moisture from the gulf that is a good set up. Are events such as this more likely or less likely to occur depending on a el nino vs la nina scenario or are these the things that help to define one pattern vs the other?
Message to Shanon: THANK YOU VERY MUCH!! Just one minor adjustment to what she posted …. I DROVE up Rte 623 from the village of Burke’s Garden to the south ridge (last 3 miles were packed gravel road, which was neither dusty nor muddy), THEN hiked the short but VERY STEEP way up to the lookout that one of you great bloggers told me about yesterday. {If I had hiked all the way up that dirt road, either I might be reaching the App Trail now, or EMS folks would be carting me to the nearest hospital …. I can still walk quite a ways, but not steep uphill like that} Blacksburg Mike, was that you (who told of the lookout point just 1/2 mile south on the App Trail)?? Anyway, THANK YOU!! We need someone to go up there and do a bit of “tree work” and top off a couple of the trees that hinder the view from that rock outcropping. I bet 10 and maybe even 5 years ago there was a completely unhindered view of BG valley to the north. Still, the view was terrific. cloudless blue skies overhead, the rim and some of the valley were differing shades of green, and then the pale white of the foggy areas. I was there about 9 AM.
A couple of other notes … there was one of those official Natl Park Service small plaques embedded in the huge rock at the lookout point, and it mentioned the “official elevation” but the number had either been removed or rubbed away. I will use Google Earth in a few minutes and find out the elevations of a couple of the key spots there. I bet the elevation at that huge AT boulder began with at least a “3.”
On Saturday, September 29th there is some sort of festival in BG, something about a Fall Festival. If any of you are interested, you can probably find out more by contacting Tazewell County govt.
The elevation at the picnic area about a 1/2 mile south of the former General Store has an elevation of 3080. Inside that covered area, as someone posted yesterday, are some weather statics.
Alltime high temp: 96* on July 16, 1954. Coldest ever: Minus 26*F on January 27, 1987 (NOT 1-21-85 …. hmmm). Average temp: 49*. wow, that is one COOOOOOL avg. temp for a state like Virginia!!
Maximum rainfall: 63 inches in 1972 (I wonder if 2004 came close). And now for the number that may stir another 30+ comments here: Maximum Snowfall was a upstate-New-York-like 112 inches during the 1977-78 season. If I had been the letter carrier for that wonderful valley that winter, I would have probably resigned, assuming I didn’t kill myself by skidding off a snowy/icy road into a tree.
When I left the AppTrail I came back down (northbound) SR 623 into BG. By then (roughly 9:30) the fog was gonzo and after taking a couple of side roads to see what was in the western half of the valley, by the time I got back to the picnic area it was almost 10 AM and fully sunny and the temp on my car thermometer was 57, so it was prob’ly really 55. I had a tiny thermometer with me, and the readings at the BG Gen’l Store (43* at 8:20) and at the APP Trail and Rte 623 (48* at just before 9 AM) were taken with that.
Elevation at the place where the AT meets Rte 623 is about 3860′, and of the rock outcropping was 4030 ft., both according to Google Earth.
One more thing for right now. The entire BG area was fairly lush. No signs of parched lawns or fields. But I wouldn’t call it emerald, either.
Most numerous animals I saw were cattle, of course, but I did see one smaller field with about 20 goats, and lots of cornfields. I stopped by one cornfield and noticed that there were still unharvested husks on the stalks. First or 2nd planting? Even in New England, and even in a late spring, corn is harvested in August. I am just curious.
Another great day weather wise,low here this morning 50,High today 78.A.C.has been off since last Saturday.I`m looking forward to the cooler weather again next week.Leaving for Nags Head N.C.This Sunday, hope its sunny and nice for next week.Hey Doug Griggs really enjoyed your post about Burkes Garden.It was very interesting to read!
Last question first. Mr. Griggs, that was the first and only planting those folks will get in a year. When you look at average temps, that should tell you last frost/freeze date in the spring. I would guess it’s middle of may/first of June, so two plantings won’t ever work up there.
Nurse Snow- Roanoke valley is usually good to go til mid/late Oct. on first frost, but don’t take that to the bank. Higher up you go, then earlier in valleys. Lettuce, yes, turnips are doubtful. KM can correct this when he checks in. For me, it;s pushing the season.
Leo Lady, ain’t KM, but I can tell you up front, at that time of year, the weather can be great. One day later, it can go all to pieces. A good rule of thumb for an ocean area is carry it and hope you don’t need it. Cold up here is just that- cold. A SE wind at MB in late Sept. can be miserable. Either that or find a DG store and figger on buying some insulation. Not trying to answer for KM, just what I have found.
WD’s numbers are pretty much right on the money for frost/freeze
Oct. 22 is the date I figured up as the average first-freeze date for Roanoke since the current weather station at the airport was established in the late 1940s. Roanoke has never on record had a September freeze before.
Frost can sometimes occur when the temperature at the 6-foot level, where it is recorded for official purposes, is 33-36F but right at the surface it falls to 32. That’s temp range has never been earlier than Sept. 22 for Roanoke.
Blacksburg has had a 32 temp as early as Sept. 14, 1975, and a 33-36 reading as early as Sept. 5, 1982, but generally early October is the expected first frost/freeze timeframe.
This map from the National Climatic Data Center shows the date at which there is a 10 percent chance of a hard freeze — 28F. It generally shows this date is Sept. 15-Oct. 1 west of I-77 and Oct. 1-Oct. 15 most other places in our region.
http://www.ncdc.noaa.gov/img/climate/freezefrost/Fall28F_lowres.jpg
Trevar: Generally, you get a bit better odds of the “ideal winter storm” pattern during El Nino rather than La Nina, which has a tendency to park a high off the Southeast coast and deflect cold fronts and storm tracks into the central U.S. The developing setup seems to be more driven by the stuff happening up north, though, with high pressure building in just the right places to squeeze the cold air south.
The cold outbreak starting late next week has a chance to truly historic, with record lows possible. I think the core of it will set up to our west, more in the Ohio Valley and Upper Midwest, but we’ll have some unseasonable chill out of this before it’s over.
Make sure your furnaces are working and you might at least give some thought to how to protect sensitive plants if this goes off the deep end for us and we get some kind of ridiculously early frost. I think it’s within the realm of possibility looking at the upcoming pattern, especially west of the Blue Ridge.
Climate Prediction Center hauling out the deep blues now — 70 percent plus of below normal temps in the Great Lakes region both in the 6-10 and 8-14 day periods.
http://www.cpc.ncep.noaa.gov/products/predictions/610day/610temp.new.gif
http://www.cpc.ncep.noaa.gov/products/predictions/814day/814temp.new.gif
Mr. Griggs, my answer was a condensed type. Corn is usually between 75/90 days to harvest, discounting some hybrid varities. What’s grown there is livestock feed. If a frost gets the young plants later than usual, there’s usually still time to re-plant. However the long maturity dates and the growing season up there totally eliminates a second crop. In fact, there isn’t a second crop on any corn in a climate similar to ours that I’m aware of. Futher south maybe, just ain’t heard of any. A combination of wet conditions and late freezes dictate planting time. And they can vary greatly.
Leo Lady: Yes, you might want to consider taking a bit warmer clothes than usual for the coast. Won’t be as cold as here, and may not be everyday, but I’m betting many days in the latter half of the month are below normal even for the coast.
HPC starting to buy into the southern low scenario for significant rainfall early next week:
http://www.hpc.ncep.noaa.gov/qpf/p120i00.gif
0Z Euro model 10 days from now: A river of blue — 6C or more below normal temperatures (11F or more) at 850 mb, about a mile up — all the way from here to Siberia.
http://raleighwx.americanwx.com/models/euro/00zeurohourly850mbTempAnomalyNA240.gif
Another interesting Euro map just 7 days out — upper-level low-pressure troughing in blue digging all the way south to, oh, about Mexico City.
http://raleighwx.americanwx.com/models/euro/00zeuro500mbHeightAnomalyNH144.gif
The corn fields at my parents house were just harvested 2 weeks ago on Saturday. And that is the one and only planting of corn they will have in a season. Lots of doves hanging out there since then, which my hubby had great hopes of hunting. His mistake was taking our 4yr old son and 8 yr old daughter with him LOL. They found it more entertaining to run through the woods trying to scare the squirrels
One thing, b/c of my daughters interest, we noticed there were TONS of acorns this year. Does anyone know if this might be significant in predicting a harsher winter?
Weather channel must not be picking up on the cold snap, they have temperatures in upper 70s through next weekend. Doug, neat hearing all this talk about Burke’s Garden, most of my kin folk come from that area of Tazewell and also Bland county. My Great Uncle told me of some winters back in the early 1900s when the great flu epidemic happened people were just laid outside until they had a chance for burial. The cold kept the corpses froze. I think it was sometime in the 19 teens. I’m sure it was interesting living in those areas before the comforts of today was introduced!