Warm, dry December turns a little wetter next 2 days, then much colder next weekend
Now about halfway through the month of December, the balmy start to the month has put back into play the possibility that 2012 could be Roanoke’s warmest year on record, something I wrote off as recently as Nov. 21. The first 15 days of the month averaged 48.2 degrees. The month as a whole would need to average 46.8 for 2012 to surpass the yearly average temperature of 59.6 from 1931. It would need to average 45. 6 to at least tie that mark. An expected cold shot of air next weekend will likely bring the month’s average down quite a bit, but it still has some room to drop, especially if we rebound to somewhat milder weather after Christmas. After the last 2 months of the second-warmest winter on record, the warmest March on record starting off the warmest spring on record, and then the hottest July on record splitting a summer that was fairly mild on the front and back end, it appeared that cooler weather in October and November had derailed the year’s obvious march toward record status. The first 60-degree average year appears to be off the table now, requiring a 50.4 average for the month. (Incidentally, 47.8 is the record warmest December for Roanoke, set in 1956. Last year’s 43.8 was the 8th warmest December … and the 31.3 average of the previous December in 2010 was the fifth coldest.) But a record tying or setting year is still possible — unless next week’s cold spell hangs in for the balance of the year. Joining 1921, 1931, 1990 and 2007 as the fifth 59-plus degree year is very likely. Nationally, 2012 is virtually assured to be the hottest year on record, dating to 1895.
Back to the here and now, with rain potential. The NAM (North American Model) and GFS (Global Forecast System)models — the two major U.S. forecast models — are fighting it out about whether Southwest Virginia will be a rain bullseye or rain shadow, respectively, in regard to the storm system the next couple of days. The Hydrometeorological Prediction Center has more or less split the difference, showing our region generally around the 0.5 to 0.75 inch range over the next 3 days — more than the GFS shows, less than the NAM shows. The reason such a configuration could occur is what often occurs here, with the best moisture staying to our south while the best storm dynamics to lift and condense moisture go around us to the west and north. If you’ve lived here a few years and paid attention to the weather map, you’re all too familiar with this two-step. The good news for those wanting moisture to ease the dryness is that we are likely to get at least some, as Gulf of Mexico moisture overruns cooler surface air on southwesterly mid-level winds overnight into Sunday, triggering some showers. By Monday, a low-pressure system and cold front will move closer, adding more lift to squeeze out the moisture. Roanoke’s biggest rain since Oct. 1-2 was only 0.41 on Nov. 12-13, so it wouldn’t take a whole lot of rain to make this the rainiest system in more than 2 months. Once the cold front passes late Monday or early Tuesday, a few mountain snow showers may develop on northwesterly upslope breezes, but the air mass behind it is not that all that cold, and southwesterly flow ahead of the next storm system tracking northwest of us may get us close to 60 again in some spots by Thursday.
Late week, a surge of Arctic air remains likely Friday into the weekend, with blustery northwest winds, highs not topping 40 on at least a day or two, and the potential for a more vigorous round of upslope snow showers. Forecast models today do want to move low-pressure over the Great Lakes eastward a little faster, rather than stalling it, so a multi-day snow shower event appears less likely. Next week has lots of questions with it, but on the whole, it appears likely to be the coldest average-temperature week so far this month — not a terribly impressive feat, considering how mild it’s been, though there is at least some model support for a very cold Christmas week — with perhaps some potential for a storm system in the days after Christmas. Whether the temperatures rebound after next weekend’s cold surge, or remain at least seasonably cold, will go a long way to determining if a potential system after Christmas would bring wintry precipitation or mainly rain.
December 15, 2012 - 6:48 PM
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After a high of 50 today,its now back down to 44 with cloudy conditions.Just checked the radar and rain is all around us.Everyone have a nice evening!
Thanks to all the kind replies about the website. Glad ya’ll like it.
When I get time, I will eventually eliminate the Gotcha Codes.
If the Codes are too muuch to handle, leave your comment here or tweet me @quagmirewx or shoot an email at quagmireweathercentral@gmail.com
Forgot to mention the 12Z Euro Ensembles still have a major snow potential for just after Christmas. Believe it or not, tonight’s 18Z NAM showed the same thing. coincidence?
More Sunday
All right, enough is enough. Desperate times (for Greater Roanoke’s horrendous rainfall situation during the past 10 weeks) call for desperate measures.
“KHAN, LIKE A BAD MARKSMAN, YOU KEEP MISSING THE TARGET!!!”
Rain, including some radar-indicated heavy stuff, is traveling the I-64 corridor from west to east. Here? Nada.
The post-Christmas storm has been on the extended GFS model for about 5 days now, most runs at least. Variations in track and temperature structure, as would be expected. Hopefully by next weekend we’ll have a little better idea of the fact-or-fiction level of what we’re seeing. Recall that 4 or 5 days ago this showers over 2-days event we’re seeing now was depicted by some models as a massive coastal low with heavy snow over us.
I hear raindrops pecking on my bathroom skylight … and some decent returns on radar. We’re going to get a little wet, at least.
We had some rain during the night – I heard it hitting the window but it seemed like it did not last very long. Now this morning there is fog building in the valleys under cloudy skies.
I meant to say that it is currently 39 up here on the ridge and we had “0.22″ inches of rain.
It looks like the mild Pacific air will rush east and take over our weather pattern around say, December 24th (following a brief cold shot from December 21-23). Christmas looks to be above normal. Looking more and more likely that there will NOT be any significant, prolonged, cool down through New Year’s at least. Oh well.
At 7:30, 38*, overcast, 0.1 inches in RG (no puddles in driveway).
I am not expecting a 2-week Arctic outbreak or anything like that out of this, Blacksburg Mike. Maybe decently cold a couple more days beyond the 24th, though. I think there is a chance that the storm system being advertised around 26th-28th takes a northwest track and brings in milder air. Or even if it is farther south and we get wintry mix or snow out of it, it may be a “pattern changer” that leads to milder weather afterward.
Latest European model is still cold on Christmas morning, but starting to modify the air mass near us:
http://raleighwx.americanwx.com/models/euro/12zeuro850mbTSLPUS240.gif
I would say from my amateur knowledge of the “teletubbies,” I generally agree with your assertion, Blacksburg Mike, although the move out of the truly cold air might be a couple of days later than what you mentioned. NAO looks to be rising during that period. On what websites or models did you make your prediction/statement?
For everyone’s info, Kevin’s 9:57 comment had not appeared on my screen until after I posted my comment.
Interesting that most of these indicators we watch seem to be headed toward “neutral.” Can’t immediately remember the last time it was ENSO neutral, PNA neutral, NAO neutral and AO neutral all at once. If it verifies, it would suggest a “progressive” weather pattern entering the new year without blocking systems or strong features stuck in place. Alternating periods of cold and mild with few extremes. Probably would offer a better chance of rain and snow than the pattern we’ve seen the first half of December, but probably not a lot of either.
Some of us have a tendency to mention other regions of the country once in a while, or of Virginia, and in the case of folks like Jared and Mike of Marshall (or “I’m in DC”), that is fully appropriate, because they live there. My tendency is for the New England states, because I lived in New England for almost all of my first 30 years.
Bangor, Maine: they have been a bit warmer than normal so far this month, with only one day (the 1st!!) having a reading in single digits (5*). Nine days have had a high temp of at least 2 degrees warmer than normal. But not today. High in the mid-teens (according to wunderground). Their normal highs and lows are exactly 14 degrees colder than Roanoke’s now. Today that diff might be 40 degrees for the expected high temps, but on this coming Saturday it might be only 6. ROA 38, Bangor 32.
In case any of you are curious about the weather for tonight’s NFL game of San Fran at New England (in Foxboro, Mass.), 37* and 60% chance of rain showers or maybe even lonely snowflakes.
Thanks very, very much, KM, for your thoughts about what all-neutral teleconnections would mean. Makes sense. Of course it hasn’t happened yet, either. Those 10-day and 14-day outlooks can once in a while be quite a bit off.
I would not expect it to all stay “all-neutral” for long. Probably would be a transition period of a few to several days toward something more definitive.
On another matter, the radar pattern this morning certainly leans more toward the GFS idea of heavier rain south of us, and the NAM has also moved more that direction. But we still could get some half-inch amounts — and keep in mid that those places south of us getting heavier rain are also in moderate or even worse drought.
Started out at 39*, now up to 43*. A plumb chilly, disagreeable day.
I HATE IT WHEN IM RIGHT! Pattern change has been pushed back into January with no cold air in foreseeable future! Ding DIng the winters dead! LOL Oh well guess I will have to get use to this. Seems like its becoming yearly now.
No, Jared, the pattern is changing — it’s just not changing to exactly what you want it to be.
No cold air in foreseeable future? It’s coming next weekend. It just might not be around for weeks.
Would like to ask one question? Where is the terrible cold winter at that we were supposed to get from this huge snow pack in Siberia and Canada? Wondered why I hadn’t seen Tolleris on Facebook gloating about the now pretend Christmas storm, which he started calling the DT storm yesterday! LOL
If its been warm fir a month now and only gets cold for 3-4 days and goes back to warm again, how can that be w pattern change?
Because weather patterns are about more than what happens at your front door. They are about the entire structure of the atmosphere across the nation, and the world. The fact that we can get any Gulf moisture, a southern-stream storm (possibly a second after Christmas) or any deep Arctic air mass, even for a few days, are signals of a different weather pattern, not quite what it was before, but not necessarily quite what you are looking for.
Some of our worst cold periods historically have come in January and/or February after mild Decembers. Others have come in December and lifted for the latter part of winter. Some of have more or less hung on all three months. If we get to mid-February with no extreme Arctic air and no sign of it on the way you’ll have reason to question DT’s and others’ predictions based on the Siberian snowpack.
It’s also not certain we’re going back to “warm” after Christmas. Doubtful that this shot of true Arctic cold holds on past maybe somewhere in the Dec. 25-28 range, but that doesn’t necessarily mean we’re shooting back into 60s/near 70 highs either.
Have to agree wid you Jared. What it boils down to is this: The best the govment’s got still don’t know jack. I found this out close to 50 years ago while plowing snow. They couuldn’t get it right then, but were as close as they are now. All the excuses that are offered is nothing but face saving. And a terribly red face at that. And there’s no use in anyboby telling me I’m wrong. Close to 50 years of first hand watching tends to clog up my ears.
However, I sho do like how my woodpile is holding up and the furnace ain’t playin me da blues.
Is it the Pacific that’s preventing long term sustained cold from our region? Is there a correlation between temps in Alaska and temps here? It’s 40 below zero now in Fairbanks and 60 above here. Plenty of times I’ve known it to be relatively warm in Fairbanks, AK and severely cold in Virginia. Is that a general rule? Mild in AK, cold in VA. With all the severe cold bottled up in Alaska and Canada what’s keeping it from coming down? Is it normal for any real cold we may get in the mid-atlantic to last only about a week at a time? Also, I think MECS (Major East Coast Snowstorm) are rare and from past experiences occur mainly in February for the mid-atlantic area. I enjoy your posts. Merry Christmas.
I’m a little confused, wd. The government forecasters in this case have never predicted a prolonged Arctic outbreak or a post-Christmas winter storm. Whatever the merits of your historic argument, in this case, there really has been no major change in the long-term forecast from the National Weather Service. Some private entities suggested a snowstorm or prolonged Arctic outbreak may occur, not the weather service.
Accuweather has all but obliterated all the cold air in their 3 week forecast, NO mention of snow anymore and no highs days on end in the upper 30′s and lower 40′s. I’m done with winter and it hasn’t even started. I am NOT looking on Accuweather anymore. I HATE the way technology is now that can tell you if it’s going to be cold or warm for an entire month and make or break your entire winter. I miss the one day at a time approach on winter predictions that didn’t constantly have model enthusiasts ramble on incessantly about PNA, NAO, GFS model, Euro model, etc….I miss the mystery in winter of not knowing about an impending snowstorm until several days beforehand, NOT advertising them weeks in advance, and NATURALLY they never pan out or materialize. Jared, I agree with you, December is a done deal as far as true cold is concerned! I am so disgusted! Jared, BTW…hope I didn’t weird you out sending you that FB message saying…I’m snow’s #2 fan. I saw your FB profile floating around on some site and I thought, that’s got to be the same dude! Anyway, hate to sound negative Kevin but I’m nervous for this winter!
Stephen: Generally, that is exactly the case — cold Alaska, mild Virginia. And reverse it, too. Remember how Vancouver in western Canada didn’t have snow for a few skiing events in the 2010 Olympics when we had piles of it? It’s all part of “teleconnections,” or how the weather pattern in a distant location affects another far away. Actually, you are also right that short shots of cold are common here in winter, much more so than long-term Arctic outbreaks. We’ve gotten many significant winter storms out of very short-term cold intrusions … and quite often got very little snow out of weekslong Arctic invasions.
The 8-14 day temps by NOAA say BELOW NORMAL TEMPERATURES, but it’ll flip-flop to warm again soon, I guarantee it! Never has there been so many flip-flops on models and the so called….pattern changer. I only like flip flops at the beach!!
OK … let me pull back on my 9:57 a.m. comment — I see where all this talk of warmth is coming from.
The 0Z Euro DOES bring a warmup back by Christmas, as Blacksburg Mike noted first. The site I get the Euro from was sticking on yesterday’s models.
http://raleighwx.americanwx.com/models/euro/00zeuro850mbTSLPUS240.gif
So as of 0Z, the Euro was depicting an even shorter shot of cold air this weekend. That’s where a lot of these forecast changes stem from that I’m seeing mentioned.
Doug – my comment about the cold air not lasting past December 24th, and the fact that the mild Pacific air will take over again, was extrapolated from Ray’s Weather Center (NW NC Mtns), which KM has linked to the right. Ray is one of the best in the region at forecasting, and between him and KM the information is about as good as it gets. He does not see any long lasting cold arriving anytime in the forseeable future. I do agree with KM, though, the pattern is changing, it is going from “very warm and dry”, to “normal and a little wetter”. The problem for snow lovers, is “normal and a little wetter” does NOT at all mean snow in our backyards. As a snow lover I also empathize with Jared, because there is absolutely no reason to get excited about snow, at least not in the next two weeks.
I will say I think the NWS is going to be way off on our high today. Currently at the airport it is only 44-degrees and a chilly cloudiness. The projected high was low-mid 50′s. I don’t think it will make it because of the deep cloud cover, unless it either clears up or some kind of temperature inversion situation were the temps warm up at night!
I’d still make sure this sticks. It is one forecast model run, and even the Euro jumps back and forth sometimes. This one is cranking up a huge storm in the central Plains, which is a totally new solution from previous runs. When you see something come out of the blue like that, there are yellow flags that go up.
In any event, I’ve never seen this as more than 3-7 days of Arctic air, and have had lots of doubts about the Dec. 26-28 storm being snow. Looks far more likely to take a NW track and pull milder air in with it. Maybe not as far NW as the current Euro.
Eastern Pacific still controlling the pattern, though it is subtly shifting to what Blacksburg Mike says: “normal and a little wetter.”
A quick question? Where and how are the models, maps, AO, NAO, PNA, EL NINA, EL TORO and all the other data that’s put constantly originate?
I’ll say something positive….we are at least getting some soaking rains finally to help a bit with the drought and give me a NORMAL day in December of 45-50-degrees with some drought quenching rain…ANYDAY…to temps in the 60s-70s in December, sunny and bone dry! I hope and pray January gives the snow lovers some bit of satisfaction, because it’s not happening this December! Like Kevin has stated before, some very snow winters in the past, yielded snowless Decembers. 1986-1987 is one example. I remember we had a moderate snowstorm to cap off that year of January 1st of 1987, may have been a 3-5 incher. I remember it started out as a Winter Storm Watch and was downgraded to what they used to call a Travelers Advisory, now they call them Winter Weather Advisories when the snow is less than 4 inches and/or ice accretions are less severe.
I see the forecast as something that changes all the time, and I am not sure why people seem annoyed with it. I have seen storms come from a day or so out, and then I have seen warm days pop up after being bitterly cold, with very little indication in the forecast. The truth is we’re sill far out for predicting Christmas weather, and it may flip-flop 2-3 more times.
Where are these rains Scott? Not here!
EVERYONE RELAX!!!!
SUNDAY 12Z EURO SAVES THE DAY!!!
WILL UPDATE WEBSITE SHORTLY.
Quags says game still on. But I didn’t which game…
It never ceases to amaze me when the best efforts at forecasting are berated so. Mother nature and the original manufacturer have been working on this for literally millions of years, and it is surprising when our best technology and data that have existed only 40-50 years can not compete? That is why I rely primarily on KMs blog, he is quick to mention potential weather events in the next week or two, but with appropriate attention to models being guides, and often change significantly from two weeks out to two days out. I only go to accuweather now to see what potential events are being discussed in the forums, but with Doug, Quags, Kevin, and others here I really don’t have to to that anymore.
Jared…maybe you guys didn’t really get much rain your way, but I woke up this morning, near Fincastle, to the rain pouring down, the likes of which I haven’t heard in a while. It probably didn’t accumulate much due to the drought stricken ground, but it actually woke me up. It did so in spurts for several hours and abated. Most of the day in my vicinity has been cloudy, chilly with intermittent drizzle. It may have soaked us some, but by know means was a drought killer!
Trevar, you nailed it when you said efforts at forecasting. With the exception of KM, I don’t pay any attention whatsoever to a forecast. My position on weather has been stated many times on this board. I don’t care what it does, with the exception of percipitation which we need more of. What kind, makes no difference. Temps make no difference, altho mild temps helps with the heating. So I don’t have a horse in this race. I do have an opinion and I stated it. Disclaimers are welcome. Let’s start with yours.
Blacksburg Mike, thanks for your reply and info.
My gage shows 0.12″ thru 4:30 PM. Sounds about rite. One big batch plumb back to the Gulf coast and it seems to be trending to our south as it has all day. We need it, but they do also. A couple of times a week won’t be any too much, if even enough.
Picked up 0.13″ of rain today. SW Roanoke City.
DC, good soup day.
As Quagmire alludes to … 12Z Euro back to holding the cold in through Christmas, and taking next week’s storm system through the Ohio Valley. Seems more realistic than the 0Z Euro Central Plains storm with a Christmas blowtorch here.
Here’s the Christmas Day model (I’ve double-checked, this is correct frame):
http://raleighwx.americanwx.com/models/euro/12zeuro850mbTSLPUS216.gif
And day after Christmas:
http://raleighwx.americanwx.com/models/euro/12zeuro850mbTSLPUS240.gif
I do see a hint of a cold air damming signature, but at this stage on Day 10 of a model that’s already flip-flopped hugely in 24 hours, it’s just about meaningless.
WD:
Sadly for American prestige, the proven best forecast model in the world is based out of Reading, England — the ECMWF, or European Centre for Mid-Range Weather Forecasts, from where we get the European model. The GFS and NAM are operated by NCEP — National Center for Environmental Prediction — which is a National Weather Service entity.
Forecast models are intended to be tools and not automated weather forecasters. What I was referring to as the government forecasters not predicting a prolonged Arctic outbreak or post-Christmas snowstorm were the outlooks from flesh-and-bone meteorologists. I would say in general forecasting is getting better by leaps and bounds on big-ticket items — Superstorm Sandy being a big example — but still hard-pressed to nail the chaotic, local day-to-day stuff. The weather service does an excellent job now of projecting a widespread tornado outbreak 3+ days in advance, but a situation like Pulaski where there is 1 or 2 tornadoes in the whole U.S. is troublesome. Most of our winter weather events are fairly weak or subtle features, not major storms, and therefore difficult to forecast.
We are sitting at “0.33″ inches of rain so far for today. Every little bit helps!
wdbrand -Not a soup day here but a Thanksgiving/Christmas meal. Soup tomorrow.
wd…
Thanks for the comment on the website. We’re all good. Kevin just answered the question in #49 above. As for your earlier question in # above about the “Tele-Tubbies”, DT on his Facebook page had a thing about the Euro’s model supremacy and how NOAA just didn’t have the computer power that the ECMWF has. I’ll try to find it and explain on my Blog.
For now, Kevin nails it above.
Temp is 53.2* now so southerly winds have kicked in. Saw this earlier while looking at DC’s site. Warmer than I was.
Temps have shot up around 8* in the last 15 minutes.Now 55.2*
Kevin, you mentioned a hint of cold air damming in a previous post @ 5:05 pm where you linked to the 12Z Euro. Could you explain what feature of those panels hints at that? Thanks in advance.
Alfred: Posting the Euro link again here for Day 10. You can see an H in SE Canada signifying high pressure. Also notice how both the isobars (dark lines) and the colored zones for temperatures at 850 mb seem a little “bent” for lack of a better word as you work your way southwest through Virginia and the Carolinas. That is the hint of cold air damming, cold air forced south/southwest by the high in Canada banking against the Appalachians. Taken literally, it wouldn’t be cold enough for wintry precip south of northern Virginia, but details like that aren’t going to be very accurate at this range. If this cold air damming pattern exists and is just a little stronger, even the projected low track through the Ohio Valley here (which also may or may not verify) could yield some wintry precipitation along and east of the Appalachians.
http://raleighwx.americanwx.com/models/euro/12zeuro850mbTSLPUS240.gif
Way too far out to predict anything like that, but cold air damming is a clue to watch for as the models work toward an event.
WD, I’m still at 43, just south of Roanoke at 1400 feet.
Some of that warm, moist air from the southwest is working in at your elevation. Temps around the area show mid 50s at Hillsville and Mountain Empire Airport (Marion-Wytheville) while it’s in the mid 40s at Roanoke Regional Airport, sort of a reversal of what is normally expected because of elevation.
Thanks for answering my question.
wd and DC, I am like Kevin’s temp. Still at 44* here now at 1420 feet elev.
It is that. But at mine and DC’s elevation it seldom happens on cloudy days. Is that some cold air damming?
A quick look at wundergrounds PWS site tells the tale.
There is some cold air damming. More of an “in-situ” wedge caused by rain and evaporative cooling rather than damming caused by a high to the north circulating winds southward.
Dopplerville 7 pm Report – Currently 48 and rain gauge says we have had “0.36″ inches of rain so far today
Kevin, I just want to tell you that I really appreciate everything you do here…. I usually only come here when I need weather updates…. I appreciate the fact you dont hype the weather, call it like you see it, and dont take anything too serious on a far ahead model…. I know its useless to go to check out a 10-20 day planner on Accuweather or Weather.com, and I know there are companies out there that hype that weather just to get more viewers…. sometimes I feel you get far too little credit, and at times some unnecessary grief, so I just wanted to say thanks for all you do….
Only made it up to 46 here today.They were calling for low 50`s.Back down to 43 now with light rain falling.Also had some light rain last night.Jared in Greene hope your finally getting some rain down in your neck of the woods.Its been a good day Redskins won again,5 games in a row now still can`t believe it.Hey snow lovers if the skins can win 5 in a row than i believe we still have plenty of time for some snow.Have a great night all.
Nice slug of moderate to locally heavy rain working up the I-81 corridor now, about to overspread the Roanoke and New River valleys.
The temp here has crept up to 47.5 degrees. I am about to walk Lame Legs, who FINALLY ate a decent meal a couple of hours ago. Pausing ……
It is actually raining lightly here. But “heavier” than lonely raindrops. I doubt if we have had any more accum. yet, but we will if the liquid keeps advancing this side of Poor Mntn. Mini – Yay.
Mike in Marshall, congrats to the Redskins. “My” New England Patriots were world beaters last Monday night, but they royally stink tonight. Down 17-3 at halftime, and SF easily could have had another 10 points. SF already has over 100 yards rushing and over 200 passing!!!
Will update Monday.
Just too tired right now.
Good rains coming this way.
goodnight all
Cowboy fan here! Mike in Marshall, looks like the last game of the year is going to be for a playoff spot. May the best team win! This time we will have Demarco Murray, unless he gets hurt again.