Good Monday and welcome to the first full week of December. Spring is in the air on this Monday as mild temps and scattered showers dominate the day. Snow and cold lovers across the country are left out in the… mild. Most are probably thinking here we go again. Well… hang tough. The change toward winter continues to show up very strongly later this weekend into next week.
Let’s start with the mild present. Temps today will be well into the 60s again and a 70 is possible… especially across the south. Scattered showers will be noted with a rumble of thunder possible.
The first of many cold fronts over the next few week shows up by late Tuesday. This front will spark a line of showers and thundershowers that rolls eastward across the state. Locally heavy downpours will be likely by the late afternoon and evening hours. Winds will be gusty and temps will come way down behind this front. Highs Wednesday and Thursday should stay in the 40s for many areas.
As you know, I’ve been targeting the period of December 7th-14th for a big change in the pattern that will lead us into winter. There is little doubt the pattern is going to drastically change during this period and will likely set the stage for several shots of cold and snow threats for the middle and end of the month. Take a look at this snippet from the HPC extended forecast discussion:
MODELS AND TELECONNECTIONS
PREDICT DEVELOPMENT OF A BROAD SCALE POSITIVELY TILTED
TROUGH…SUPPORTED BY INTRUSIONS OF ARCTIC AND MODIFIED ARCTIC AIR
INTO THE CENTRAL/EASTERN STATES.
They are now sniffing out this huge pattern change to a deep trough across our part of the world. Once that gets locked in, it should stay there through Christmas. The only real question I have is, exactly how does this trough get established? That’s the real question to tackle this week and I’ve been doing a lot of research on similar changes during December and one thing stood out. Most of them had to go through a lot of rain to get from the mild start to the wintry stuff.
This coming weekend looks wet around here as our trough slowly digs in across the middle of the country. This causes a front to slow down across the Ohio Valley by Friday. Waves of low pressure will ride northeastward along this boundary and that should allow for rounds of locally heavy rain across this region. That’s a good thing because we are getting pretty dry again.
The series of lows should feature the final one as being the bigger of the bunch and feature more of a wintry aspect after it passes by. I suspect that low will track over us or just to our west and could result in a huge temp jump and dive. Timing these waves of low pressure is an impossible task for the models and they will feature some wild swings in the coming days.
Again… I’m only talking about timing and placement of the lows this weekend and NOT the change toward a wintry pattern. I showed you a series of 500mb maps from the European model with my last update and that still looks good through next week. To illustrate this thing likely locking in… check out the GFS Ensembles 500mb Height Anomalies even farther down the road…
Buckle up for the ride into winter… it’s gonna be bumpy one. 😉
I will update things later today. Have a great Monday and take care.
Thanks Chris. Brrrr! 🙂
Chris, I have no doubt that you will figure out the whole grand scheme. I love that you spend so much time researching past years and how things came together. Your devotion is greatly appreciated.
Also, you have such a delightful writing style. Reading this blog is a real pleasure.
Thank you for keeping us informed and entertained. 🙂
Ah jeeesh, here we go AGAIN! 😉 Sorry, I could not resist. 🙂 At any rate, not long to find out if the change in weather shifts out as time progresses- a sign of a more moderate change. I think (FWIW) CB is correct in the outlook, but I can not shake the trend of results.
I am thinking the change does happen, but KY could be the fence again. One more time, we need Tennessee to be the fence, or it will be rinse and repeat for snow chances beyond itty-bitty snows for a lot of the state.
We’re almost always on the fence when the warm moisture to the south and the cold to the north collide. After last year’s sad winter, I’d be happy with two good 6+” snows this year. How about one the weekend before Christmas and another one in late January? Get ‘er done, Mother Nature!
“Winter Waiting Games” Sounds like a new movie coming out this winter, it will probably leave all of us in “hunger” (as far as snow is concerned)
Thanks, Chris. Sounds like we may finally get some much needed rain over the weekend and beyond. also sounds like I will need to pull out more of the winter stuff. Appreciate all the research you do. That makes it even more interesting. Have a GREAT Monday, everyone!
Ky Mesonet showing widespread temps in the 70s. Only question now is will all-time December record highs go down today at any official reporting stations.
===i guess it is true what they say, winter really is the new spring.
I like a good snowstorm in winter, but if this weather stayed until march I would not cry, and also my electric bill would be sweet!
you would cry at your grocery bill prices would go up its been dry every where
CPC says what cold mid-month for the eastern US? Their 8-14 day maps show a better then average chance of above normal temperatures for the eastern US.
I agree with others that Chris, while a good guy, loves to hype “potential” patterns that are often out to lunch. Maybe he will finally nail this one though.
WSAZ and the weather channel has us in the mid to upper 50 and low 60’s all the way thru next tuesday, has the cold air coming in slowed down? i am ready for winter to make its apperance!!!!!!!
I think the temps were always going to drop but then moderate again somewhat after this first front comes through. Any winter chill is still a couple of systems away.
ok thank you, i thought the models were showing poss cold coming on Sat,
Well, Fairbanks Alaska had a high of minus 29 F. Yes, the high (and that’s not wind chill).
Makes you not want to know what the low was! (-38).
Even for Fairbanks, these temps are a good deal below normal for early Dec. Snowpack for Alaska/northern Canada is also above normal.
As CB and others have been hinting, looks like we might get a taste of these Arctic conditions later this month.
BTW, 18z gfs shows monster thunder to snowstorm for kentucky on the 11th.
http://mag.ncep.noaa.gov/NCOMAGWEB/appcontroller?page=Image&prevPage=Param&image=..%2FGemPakTier%2FMagGemPakImages%2Fgfs%2F20121203%2F18%2Fgfs_namer_183_850_temp_mslp_precip.gif&fcast=183&model=GFS&area=NAMER&storm=&areaDesc=North+America+-+US+Canada+and+northern+Mexico&cat=MODEL+GUIDANCE&rname=SFC-LAYER+PARMS&pname=850_temp_mslp_precip&cycle=12%2F03%2F2012+18UTC&imageSize=M&currKey=model&scrollx=0&scrolly=170&nextImage=yes
Try this link. http://tinyurl.com/czqk737
WO MOMMA!!! That map shows heavy snow for most of Kentucky! Oh how I long for this to come true…
Let us know if the 0z GFS shows the same thing. If it does, I’m going to start getting antsy like a small child in a candy store 😉
Waiting on the snow!