Winter 2013-14 Pattern Discussion

[GaWx]

Winter 2010-11 had a freakin' White Christmas in Atlanta, followed by a major snow/ice storm in January 2011. We'd have to not get any this winter and next winter to make it 3 in a row.

 

It's only December 16th, relax a bit.

 

Lol, it won't even be one winter in a row this winter as 0.4" already has been measured at Atlanta. So, ATL is reset to 0 in a row regardless of what the rest of winter brings. Snowstorm can't complain about 0 in a row, can he/she? Also, 2008-9 through 2010-11 was one of the most prolific three year periods in quite a long time at ATL and it made that 3 year period WAY above the average of 6".

[toxictwister00]

Lol, it won't even be one winter in a row this winter as 0.4" already has been measured at Atlanta. So, ATL is reset to 0 in a row regardless of what the rest of winter brings. Snowstorm can't complain about 0 in a row, can he/she? Also, 2008-9 through 2010-11 was one of the most prolific three year periods in quite a long time at ATL and it made that 3 year period WAY above the average of 6".

 

Exactly, this seems to keep being overlooked with the talk about a 3 year snowless winter. As far as I'm concerned, the slate has already been wiped clean.

[GaWx]

Exactly, this seems to keep being overlooked with the talk about a 3 year snowless winter. As far as I'm concerned, the slate has already been wiped clean.

 

Prediction: snowstorm will now say in his/her backyard there has been no measurable snow in 3 winters. However, snowstorm didn't wake up til 11 AM on the ATL snow day of 11/27/13. Does that mean it definitely didn't snow/sleet measurably in snowstorm's backyard on 11/27/13 if it wasn't seen? Mine was long gone by 11 AM. I was in Dunwoody that day.

[DaculaWeather]

Birmingham afternoon AFD:

 

OBVIOUSLY THIS FAR OUT THE DETAILS ARE HAZY...BUT THE 12Z GFS AND
12Z ECMWF ARE SUGGESTING THAT SUNDAY LOOKS TO BE THE BEST DAY FOR
THE FAVORABLE INSTABILITY/WIND SHEAR COMBINATIONS NEEDED TO PROMOTE
ORGANIZED THUNDERSTORMS FOR CENTRAL ALABAMA. BASED OFF FORECAST
SOUNDINGS...LOW LEVEL WIND SHEAR AND HELICITIES WOULD SUPPORT
ROTATING STORMS SUNDAY...WHICH MEANS ISOLATED TORNADOES COULD BE
POSSIBLE. BOTH EXTENDED MODELS HAVE THE SURFACE LOW TO OUR
NORTHWEST/NORTH SUNDAY MOVING NORTHEAST WITH TIME. NEITHER MODEL
DEEPENS THE SURFACE LOW THROUGHOUT THE DAY. BUT WE WILL HAVE TO
WATCH THE TRACK AND STRENGTH OF THIS LOW CLOSELY...AS IT WILL HAVE A
LARGE INFLUENCE OVER THE AMOUNT OF BACKING AND STRENGTH OF THE LOW
LEVEL WINDS...AND CORRESPONDING TORNADO THREAT. THE SURFACE COLD
FRONT ALSO LOOKS TO PASS OVER THE AREA SUNDAY WITH A SQUALL LINE
IN TOW...SUGGESTING DAMAGING WINDS WILL ALSO BE POSSIBLE.

IT SHOULD BE NOTED THAT THERE IS STILL MUCH UNCERTAINTY CONCERNING
THE TIMING OF THE SEVERE WEATHER RISK FOR CENTRAL ALABAMA. AT THIS
POINT BASED OFF THE FORECAST EVOLUTION AND EJECTION OF THE UPPER LOW
OVER BAJA CALIFORNIA...OUR TIMING COULD EASILY BE OFF BY 12-24 HOURS
IN EITHER DIRECTION. FOR EXAMPLE...SOME ENSEMBLE MEMBERS FROM THE
GFS KEEP THE UPPER LOW CUTOFF OVER MEXICO THE ENTIRE WEEKEND. BUT
CONCEPTUALLY THERE IS ENOUGH OF A THREAT...AND LOOKING AT HOW THE
OPERATIONAL MODELS HAVE BEEN TRENDING THE PAST FEW DAYS...TO ADD A
MENTION OF DAMAGING WINDS AND ISOLATED TORNADOES TO THE HWO FOR
SUNDAY. WE WILL BE CLOSELY MONITORING THE LATEST GUIDANCE AND DATA
THROUGH THE WEEK...AND WILL PROVIDE REFINEMENTS TO THE FORECAST
AS WE GET CLOSER TO THE WEEKEND.

[toxictwister00]

Prediction: snowstorm will now say in his/her backyard there has been no measurable snow in 3 winters. However, snowstorm didn't wake up til 11 AM on the ATL snow day of 11/27/13. Does that mean it definitely didn't snow/sleet measurably in snowstorm's backyard on 11/27/13 if it wasn't seen? Mine was long gone by 11 AM.

 

That sounds about right.  

[DaculaWeather]

That's because it sent you to the Land Of Oz; and everybody knows it doesn't snow there.

Oh no... not true! Glenda made it snow on the poppy field! Where's Glenda when you need her! 

[thunderbolt]

I keep a spreadsheet with all of the teleconnections, here's the AO and NAO, with + conditions in yellow and - conditions in blue, gradient in between. It makes it easier for me to pick out trends.

http://www.daculaweather.com/images/2013_12/nao_ao.pdf

nice work!  Dacula

[Batman]

LOL! Only if the man behind the curtain allows it (c'mon Lookout!!)

 

It's certainly too early to write this winter off but it sure would be nice for some of the long-range indices start heading in the right direction. That energy being held back in New Mexico is soooo Euro. I can't believe how much it does that 10 days out.

I was thinking the same thing about the Euro map. I am always skeptical when it hangs a trough back in the SW. Could be true this time, but it is often wrong and not progressive enough with it. Since there is still a ton of uncertainty over the timing of precipitation this weekend, It is nearly impossible to have much confidence in a solution for mid to late next week.

On the snow drought discussion, as I have mentioned before, I have had 10 winters of the last 16 with no snow on the ground IMBY. For that reason, I don't throw temper tantrums when it looks like I may not have a snow filled winter. Life would be miserable. On the other hand, winters 08-09, 09-10, 10-11 produced about 18" of snow combined IMBY! That's about 9 years worth of snow in 3! And yes, I did have snow on the ground 11-27. So technically, the short "drought" of 11-12 and 12-13 is over. I would still really like some snow this year that stays around awhile, but I've learned not to hold my breath.

[GaWx]

 Fwiw, new Euro weeklies, which go through 1/12/14, say that the stubborn SE US ridge holds for four weeks but weakens week 4. It actually looks more like a Bermuda high that extends to the SE US. Time for hurricane season lmao.

[weatherfide]

I think it is much more important to be concerned about how much rain we will possibly get over the winter. Droughts are a serious calamity down here (probably from poor planning more than anything) and I'd much rather have 30" of rain this season than a 3"+ snow storm.

 

With that being said, the pattern as of late has not been producing as much as earlier this spring and summer. We are only getting rain once a week and it's not particularly heavy  (.5" to 1" amounts each time). I know that's probably close to average, but I don't want to risk going dry and cold for weeks on end with a pattern change.

[pcbjr]

WxSouth has a nice discussion on a potential pattern change.

 

http://wxsouth.com/?cat=144

[FallsLake]

Oh no... not true! Glenda made it snow on the poppy field! Where's Glenda when you need her! 

I remember that, but no I think they were hallucinating. Just like we here in the SE do when snow flurries pass through.

[pcbjr]

Interesting dichotomy from CPC today, at least way down here (government at work, I suppose):

 

 

 

vs.

 

 

 

[DixieBlizzard]

I think it is much more important to be concerned about how much rain we will possibly get over the winter. Droughts are a serious calamity down here (probably from poor planning more than anything) and I'd much rather have 30" of rain this season than a 3"+ snow storm.

 

With that being said, the pattern as of late has not been producing as much as earlier this spring and summer. We are only getting rain once a week and it's not particularly heavy  (.5" to 1" amounts each time). I know that's probably close to average, but I don't want to risk going dry and cold for weeks on end with a pattern change.

 

Good points but can't we get a 3" snow and 30" of rainfall? (just being rhetorical, of course). The past couple of weekends have been pretty wet up this way and it looks like another rainfall possible this weekend. It has to translate well for the watershed here and the runoff downstream although the ACE have already destroyed the water levels for the season this side of Lake Allatoona. It looks like a dang creek again.

[Jon]

FWIW as far as the flow goes the Euro control mslp anomaly has been showing an active pattern around the 26th and through day 15 with lows popping off the coast of SC/NC and at day 15 what looks like a low tracking our way over TX and extreme highs in Eastern Canada and the lakes. This is the first year I've paid attention to the control but with the flip flopping OP and the fact that it doesn't really have the cold air figured out for that range I'm just looking for trends. Overall, I'm optimistic about the new year and within the next 10 days (Brick this is for you) we'll see the pattern settling in on the models, I hope. 10 days Brick!

[DixieBlizzard]

I wish we had a "Thanks" button on here but since we don't, thanks Jon. Maybe the control is onto something. Is there such a thing as a verification score for the control?

[Cold Rain]

I wish we had a "Thanks" button on here but since we don't, thanks Jon. Maybe the control is onto something. Is there such a thing as a verification score for the control?

The control is basically the operational run at a lower resolution out to a longer period. It's used to base the ensembles off of. The Euro ensemble suite is made up of 50 members plus the control run. Regarding verification, I don't know if they score it, but you'd have to think that the first 240 hours, at least, it's score would be a little lower than the operational.

[Jon]

I wish we had a "Thanks" button on here but since we don't, thanks Jon. Maybe the control is onto something. Is there such a thing as a verification score for the control?

 No prob! Like CR said I'm not sure of a verification score, it should perform lower though. See my response below to CR

 

The control is basically the operational run at a lower resolution out to a longer period. It's used to base the ensembles off of. The Euro ensemble suite is made up of 50 members plus the control run. Regarding verification, I don't know if they score it, but you'd have to think that the first 240 hours, at least, it's score would be a little lower than the operational.

The control also has analysis of initial conditions set while the Op has slightly altered initial conditions, if I understand correctly. But you're right, the control has been found in certain journals (soonest I found was 2007) to perform lower. I saw the control has performed well in cyclone tracking and intensity, better than the deterministic, but other than that you would assume it's not as good due to the lower resolution.

[Snowless in Carrollton]

Lol, it won't even be one winter in a row this winter as 0.4" already has been measured at Atlanta. So, ATL is reset to 0 in a row regardless of what the rest of winter brings. Snowstorm can't complain about 0 in a row, can he/she? Also, 2008-9 through 2010-11 was one of the most prolific three year periods in quite a long time at ATL and it made that 3 year period WAY above the average of 6".

not all areas in GA got snow back in November. Didn't "see" any snow here. Doesn't mean it didn't snow. Feb will be 3 years since I've seen snow/sleet/ice on the ground. In my 72 years living in GA I don't recall seeing a period that long with no wintry precip on the ground.

[NCSNOW]

WxSouth has a nice discussion on a potential pattern change.

 

http://wxsouth.com/?cat=144

Thanks for sharing pcbjr. Always say Robert  and Allen are the best for our region (NC). No doubt a  pattern change is coming that's different  than the one we've experienced from mid Nov- mid Dec. It all starts to slowly unravel after the 72 hour torch this Thurs p,m- Sun p.m. Be interesting to see how the table sets up the last 6 days of the month, this will be our pattern through the most part of January this year. Lets hope when the deck gets reshuffled and a new table is set it gives us an opportunity or two. Frankly IMO the pattern for mby for the past 34 days has been o.k. considering it's not even winter solstice v/s my normal climo for this period. Climo for mby say's that we usually have a 80% plus chance of seeing an accumulating snow the first 25 days of January. Accumulating means as little as a trace to 20+ inches. So for me winters best is just around the corner. 

[superjames1992]

I feel like I remember the Euro control run showing some nice fantasy storms last winter that never came to fruition.  Who knows, though?

[superjames1992]

Thanks for sharing pcbjr. Always say Robert  and Allen are the best for our region (NC). No doubt a  pattern change is coming that's different  than the one we've experienced from mid Nov- mid Dec. It all starts to slowly unravel after the 72 hour torch this Thurs p,m- Sun p.m. Be interesting to see how the table sets up the last 6 days of the month, this will be our pattern through the most part of January this year. Lets hope when the deck gets reshuffled and a new table is set it gives us an opportunity or two. Frankly IMO the pattern for mby for the past 34 days has been o.k. considering it's not even winter solstice v/s my normal climo for this period. Climo for mby say's that we usually have a 80% plus chance of seeing an accumulating snow the first 25 days of January. Accumulating means as little as a trace to 20+ inches. So for me winters best is just around the corner. 

 

Do you have any information on the climo for accumulating snow in the winter overall for our area?  I'd have to think it's 95%+.  I can't remember the last time we didn't get an accumulating snow here (maybe in the mid-90s?).  That's why I never lose hope here.  Climo says we are going to get our share of snow eventually, even if it's not much.  Even in the God awful winter of 2011-2012 we got that snowstorm on February 19th and last year we got a couple decent events (1/17 and 1/25).  1/17 was a pretty serious event accumulation-wise (2-5" in the Greensboro area with 3.5" IMBY), but with temperatures above freezing and the soil warm and saturated, it melted pretty quickly, especially off the roads.

[packbacker]

Do you have any information on the climo for accumulating snow in the winter overall for our area?  I'd have to think it's 95%+.  I can't remember the last time we didn't get an accumulating snow here (maybe in the mid-90s?).  That's why I never lose hope here.  Climo says we are going to get our share of snow eventually, even if it's not much.  Even in the God awful winter of 2011-2012 we got that snowstorm on February 19th and last year we got a couple decent events (1/17 and 1/25).  1/17 was a pretty serious event accumulation-wise (2-5" in the Greensboro area with 3.5" IMBY), but with temperatures above freezing and the soil warm and saturated, it melted pretty quickly, especially off the roads.

 

It's very rare even for RDU to go completely skunked, we at worst get a trace of snow, be funny if we got skunked this year.

[burgertime]

I feel like I remember the Euro control run showing some nice fantasy storms last winter that never came to fruition.  Who knows, though?

 

It did...a lot of them. Often multiple runs in a row. Look I'm as optimistic as the next weenie and I do think this winter will be better but the models just look blah, meh and downright boring outside of the rain which we need. Nothing on the models really indicate a flp for anyone south of the VA line. We badly need the PNA to go positive and the NAO to go negative. Seems this year the pac is giving us what we need but nothing else is really falling in line. 

[superjames1992]

It's very rare even for RDU to go completely skunked, we at worst get a trace of snow, be funny if we got skunked this year.

 

Yes, I don't think RDU has been skunked in a long time, either.  You all were at least on the fringes of 2/19/12 and 1/17/13, I believe.

 

It did...a lot of them. Often multiple runs in a row. Look I'm as optimistic as the next weenie and I do think this winter will be better but the models just look blah, meh and downright boring outside of the rain which we need. Nothing on the models really indicate a flp for anyone south of the VA line. We badly need the PNA to go positive and the NAO to go negative. Seems this year the pac is giving us what we need but nothing else is really falling in line. 

 

Ah, that was what I thought.

 

I will be on vacation from January 4th-13th, anyways, so I don't care for any snow while I'm gone.  Then let's rock late January, okay? 

[WxJordan]

A lot to talk about as we move into the second half of December: Record warmth possible, severe weather possible, and a major storm developing in Europe.

 

First off, there will be record warmth across many locations in the southeast late this week. This ridge is going to really pull up a lot of warm air from the tropics, and it will provide some areas with record high temperatures this week.

 

Then, either an upper level low or large trough will march across the southeast United States. My biggest concern will be the threat of severe weather; however, the best chance appears to be strong gusty winds. While tornadoes can not be ruled out, a large outbreak over the GA, NC, SC, TN, and VA area is unlikely. Rain totals may be locally high also, as some areas could see 1-2 inches of rain in a short period of time as the front moves across the area.

 

For Christmas, it does not look white. Temperatures though look to be near average to slightly below average for Christmas Eve and Day. The only thing that could change in the Christmas forecast is if the ridge does not break down as quick as is modeled, which would probably delay the frontal passage. If this was to happen, the front may not pass until Christmas Eve. In my opinion, this is unlikely at the moment.

 

There is a lot of uncertainty in the models with the possibility of a major storm developing over Europe. This storm has the potential to change the entire global pattern. The GFS model shows this massive storm developing with central pressures dropping under 940 mb. I would not trust the models too far out because the uncertainty of this storm is very high. I think that is why you see a lot of equal chances in the CPC extended forecast, especially past ten days.

 

Right now, I am not sure if I can say which way the pattern will break. The models are all over the place, and I can make an argument why we would get warmer or colder towards the end of December. The fact remains that the AO and NAO are positive, so until I see a clear trend towards at least a neutral or negative solution, the cold air will continue to come and move right on out.

[Snowless in Carrollton]

If the storm in Europe has the potential of changing the entire global pattern, I'm assuming that would be good for people in the southeast who like more wintry type weather ?

[WxJordan]

If the storm in Europe has the potential of changing the entire global pattern, I'm assuming that would be good for people in the southeast who like more wintry type weather ?

 

Not necessarily, it could help to establish a ridge that is very difficult to move over the southeast, or it could help to bring Greenland blocking that would help to "lock in" some cold air here in the southeast. I think the jury is still out, in my opinion. In matter of fact, I am not sure which one has the best chance of happening at the moment, so I am just in a wait and see mode right now. I am watching the trends on the global models and on the indices to see which way they trend. 

[Cold Rain]

If the storm in Europe has the potential of changing the entire global pattern, I'm assuming that would be good for people in the southeast who like more wintry type weather ?

Not necessarily. There are plenty of bad patterns out there that we're not currently in. Some are much worse. But the pattern could go in a better direction, like you suggest. It's too soon to tell.

[Cold Rain]

Not necessarily, it could help to establish a ridge that is very difficult to move over the southeast, or it could help to bring Greenland blocking that would help to "lock in" some cold air here in the southeast. I think the jury is still out, in my opinion. In matter of fact, I am not sure which one has the best chance of happening at the moment, so I am just in a wait and see mode right now. I am watching the trends on the global models and on the indices to see which way they trend.

Newman! You beat me by 30 seconds. Nice red lettering there, by the way!

Edit: More like 2 minutes, but who's counting.