Winter 2013-14 Pattern Discussion

[CAD_Wedge_NC]

Another thing to keep in mind, the lowest heights in the NH are just to our north over central and eastern Canada with that massive PV. I have seen some graphics take it down to 474 at H5. It does not appear to be weakening or retro grading back towards the pole anytime soon. When the jet does buckle, big time cold comes down, as we saw this previous week in the western states.

 

Agree 100%. The cold is there and it's just a matter of time before we tap into it. The SE ridge doesn't look to be a permanent feature, but neither does the high latitude blocking. With the STJ becoming more of a player in the coming weeks, we will have more chances at winter weather.

[downeastnc]

Agree 100%. The cold is there and it's just a matter of time before we tap into it. The SE ridge doesn't look to be a permanent feature, but neither does the high latitude blocking. With the STJ becoming more of a player in the coming weeks, we will have more chances at winter weather.

 

Actually looks pretty typical for winters in the SE, 2-3 day cold shots followed by gradual warming then a storm system ( usually rain) with strong cold front, rinse wash repeat.

[Pilotwx]

Just hope the flow is not northwest on this side of the mountains. We don't want the cold to be overwhelming

[WXinCanton]

0z Euro still has a system around 180 next Monday.  Looks decent for central NC

 

Edit:Crap, I was looking 12z.  Damn insomnia!!

[NCCatawba]

0z Euro still has a system around 180 next Monday.  Looks decent for central NC

 

Edit:Crap, I was looking 12z.  Damn insomnia!!

 

It's gone and it had starting at hour150 btw.

[FLweather]

0z Euro still has a system around 180 next Monday.  Looks decent for central NC

 

Edit:Crap, I was looking 12z.  Damn insomnia!!

 

 

It's gone and it had starting at hour150 btw.

 

What yall talking about? Its still there on the 0z euro run from what I see which still is 120+ hours out anyway.. Has 1 wave this weekend and 2 around sun/mon but looks like ots

[burgertime]

Euro did have a clipper on steroids at the end of it's run for NC. Those almost never work for us here. However 6z is close for next week and it seems the models are changing everyday. As long as the models are popping something under 240 to me personally it's a good sign. As well as most models in the LR seem to be more conducive to winter weather around here. As always time will tell but I wouldn't rule out something next week quite yet. 

[NCSNOW]

We will be below normal all this week. Hopefully after tomorrows front clears the ski slopes will have several days (clear nights/rad cooling) to fire up the guns.

[franklin NCwx]

Euro did have a clipper on steroids at the end of it's run for NC. Those almost never work for us here. However 6z is close for next week and it seems the models are changing everyday. As long as the models are popping something under 240 to me personally it's a good sign. As well as most models in the LR seem to be more conducive to winter weather around here. As always time will tell but I wouldn't rule out something next week quite yet.

check the euro control.

[Shawn]

check the euro control.

 

my my @ 240.  not too many details i can see but.. that looks like something possibly wintry/special.

[Cold Rain]

check the euro control.

The control run is basically the Op run re-run at a lower resolution in order to serve as the base member for the ensemble suite. It's good to bear that in mind as we use it as a tool this winter.

[Batman]

Some interesting developments in this morning's NAO, AO, PNA indices. AO still has a wide spread, but the mean is less + than past days. A few members go -. NAO is about as neutral as you can be in the mean which is a trend toward - from yesterday. PNA shows a positive trend thru the period with each member in about as close agreement as you can have. This to me would indicate some evidence of west coast ridging as time goes by. This appears to be a positive step. Obviously, these indices have fluctuated rather wildly, but the consistency of each member on the PNA has certainly perked my interest.

[Cold Rain]

^ To add, the CFS generally shows wetter than normal conditions for weeks 1-3 with a drier week 4.  Temps are mostly near normal week 1 and then above to much above in the SE for weeks 2-3.  January still looks above normal in the East temp-wise and below normal precip-wise.  Although the indexes look to remain poor, the 6z GFS does show a progression to a +PNA pattern way out in time.  There is nothing literal on the 0z GFS or the 0Z Euro that indicates any imminent witner threat.  Like has been said, the general pattern supports cold shots, warm-up before a storm, followed by cold shots and seasonal weather.

 

A well-timed southern sliding wave behind a building-in high pressure is what is needed.  The timing of such an event will surely not be known by the models too far in advance.  Neither blind expectation or cynical discouragement are recommended courses at this point, as this type of pattern is not atypical in the SE.  The Arctic continues to generate cold highs that move into the US, the cold is on our side of the globe for tapping, and there are indications that we'll continue to see systems moving through, bringing precipitation chances.  These are all good things that may eventually align to produce a true winter storm.  I'd put the odds at around 1 in 5 to 1 in 10 at this point....not too unusual for this area.

[Brick Tamland]

Actually looks pretty typical for winters in the SE, 2-3 day cold shots followed by gradual warming then a storm system ( usually rain) with strong cold front, rinse wash repeat.

 

At least we are getting the 10 day fantasy storms this winter. But yes, looks like it is typical stuff with it being too warm when the precip is here, or dry when it is cold enough for snow.

[Cold Rain]

At least we are getting the 10 day fantasy storms this winter. But yes, looks like it is typical stuff with it being too warm when the precip is here, or dry when it is cold enough for snow.

 

That is true.  It is very typical in these parts.  You should be glad that the models are showing LR snow/winter weather.  It means that there is potential.  Last year, for example, you didn't see any of that.  Of course the potential was much less.

[Southern Track]

As Burger said earlier, the 6z GFS was a close call for this weekend. The precip was marginal, but the 850 temps were much further south than 0z and previous runs before that.

[GaWx]

At least we are getting the 10 day fantasy storms this winter. But yes, looks like it is typical stuff with it being too warm when the precip is here, or dry when it is cold enough for snow.

At least we are getting the 10 day fantasy storms this winter. But yes, looks like it is typical stuff with it being too warm when the precip is here, or dry when it is cold enough for snow.

You need to be patient though I realize WOTY campaigning is vital and you always have our support. Only ~5% of RDU's normal amont of DJFM precip. is wintry. For Atlanta metro, it is only 2-3% (3%) on northside).

[Brick Tamland]

That is true.  It is very typical in these parts.  You should be glad that the models are showing LR snow/winter weather.  It means that there is potential.  Last year, for example, you didn't see any of that.  Of course the potential was much less.

 

Yes, the potential is good. Means there is a better chance we'll see some actual snow. But even if the players on the field look good, still doesn't mean anything if they can't get a win. We need a win.

[david30]

Well here in NW MS we have just wasted 3 days of cold air, it has literally not been above 40 since Thurs eve, stayed in the 20s all day sat and this morning locked in with fog and 33.  Wish we couldve gotten snow out of it but glad we missed an ice storm, we literally had close to 2 inches of rain, thunder and lightning with a temp of 33-34 degrees Friday.

[FLweather]

As Burger said earlier, the 6z GFS was a close call for this weekend. The precip was marginal, but the 850 temps were much further south than 0z and previous runs before that.

My gut is telling me there will be a snowfall this weekend in the SE along with rain.

 

Its still 150+ hours out and details will need to be worked out. I don't think it will be a major event. But just like a couple weeks ago this weekend looks familar in terms of the longwave setup. Looks like a 2 part system.... front end rain and back end snow especially with a vortex max tracking south through AL/GA.

[FallsLake]

Some interesting developments in this morning's NAO, AO, PNA indices. AO still has a wide spread, but the mean is less + than past days. A few members go -. NAO is about as neutral as you can be in the mean which is a trend toward - from yesterday. PNA shows a positive trend thru the period with each member in about as close agreement as you can have. This to me would indicate some evidence of west coast ridging as time goes by. This appears to be a positive step. Obviously, these indices have fluctuated rather wildly, but the consistency of each member on the PNA has certainly perked my interest.

The PNA does look to go positive sometime in the LR. NAO does go negative in the short term but as you stated there is a wide spred of negative and positve in the LR. The AO looks terrible. Looks like it might get as positve as the October reading; but the AO really hasn't been on our side since early October so I say if we can get the PNA and NAO to give us some blocking we may do fine.

[rduwx]

The weekend system is still on the 0z euro and 6z gfs.  The difference between those mentioned and the 12z euro from yesterday is the track.  The 0z euro has the track further north and west causing 850's to warm.  We need the track futher south and east but still a long ways to go with this.

[Met1985]

In general I like the pattern the Euro is spitting out. No storm but keeps the cold air in the East. A step in the right direction.

[BullCityWx]

The weekend system is still on the 0z euro and 6z gfs. The difference between those mentioned and the 12z euro from yesterday is the track. The 0z euro has the track further north and west causing 850's to warm. We need the track futher south and east but still a long ways to go with this.

The problem is, as I'm sure you know, there's nothing to keep that thing from moving north. I think we stand a better chance at a 50 degree rain than a snow.

[rduwx]

The problem is, as I'm sure you know, there's nothing to keep that thing from moving north. I think we stand a better chance at a 50 degree rain than a snow.

 

I agree...Some blocking would be nice!

[Cold Rain]

My highest forecast high for the week is 50 tomorrow. Every other day has forecast highs in the 40s for, and after tonight, lows in the upper 20s to 30s. The averages for December 8 for RDU are 56/35. Should help to reduce the positive departures for the month so far. If true, the staying power of the SE ridge will once again have been poorly modeled.

[Met1985]

My highest forecast high for the week is 50 tomorrow. Every other day has forecast highs in the 40s for, and after tonight, lows in the upper 20s to 30s. The averages for December 8 for RDU are 56/35. Should help to reduce the positive departures for the month so far. If true, the staying power of the SE ridge will once again have been poorly modeled.

Ya looks like the next few weeks may come in below average. As has been posted some mets are beating the drums for some really cold air to come in next week. We will see but does not look way above average like we just saw.

[FLweather]

The problem is, as I'm sure you know, there's nothing to keep that thing from moving north. I think we stand a better chance at a 50 degree rain than a snow.

 

Thats a valid point atm. But should see how it plays out over the next few days... but considering the progressive nature of the northern stream air masses the blocking is there. Its just not being modeled correctly at the moment.

[Batman]

I am curious about the importance of a -AO in the current situation we are in. I have heard, in the past, from mets and others more knowledgeable than myself that if the coldest air (or very cold air) is on our side of the pole that a -AO is not necessary for cold/winter weather. If a -AO indicates cross polar flow, would cross polar flow really be needed if very cold air is already close by? I know how folks in the northern plains, southern plains, Midwest, Ohio Valley, and NE would answer that this week.

 

It seems to me that in our current situation, getting a more favorable NAO and PNA would much  more important to get the jet to buckle and hold longer in our location giving us a better opportunity to time with some moisture while cold air is here. Just my thoughts. Feel free to dissect.

[tarheelwx]

If we got a -AO, wouldn't that deliver the mother lode further south, but also crush the southern branch?

TW