Winter 2013-14 Pattern Discussion

[Pilotwx]

That's my fear as well because living here in the Northern Foothills we have not had one those classic ice storms in a long time , so we are due. I think Robert alluded to this being a year in which we would see quite a bit more ice.

[Tacoma]

I'm all for quite weather now if we can go back to cold and snow around Christmas.  Snow on the ground for Thanksgiving and also Christmas would be awesome.  How often does that happen.  So a quite week or two is ok with me until the cold and snow loads up again.   

[Cold Rain]

Happy day after Thanksgiving, you bunch of Turkey's!

 

Looking at the overnight stuff, as noted above, the 0Z GFS and 0Z Canadian support a major winter storm for many areas of the SE in the 240 - 300 time frame.  This is predicated on the idea that several big Arctic highs will slide into the West and press south and east over time -- a theme which has generally been consistently indicated for a few days now.  Even looking at the Euro on eWall, it is clear that it's trying to do the same thing at 240, even though it still keeps a general -PNA.  Since this idea has been fairly consistent for a while now, it probably has some credibility.  The specific precipitation/storm threats seem to bounce around in their timing, though.  We will want to continue to see consistency and will want to see these storm threats show up in T-7 day period.  So far, they seem to be caught in a stationary temporal truncation matrix, keeping them fixed, just outside the 10 day marker.

 

With respect to the LR, the AO continues it's ascent, followed by a sharp drop toward neutral.  After that, there is, as usual, great spread, with most members keeping it positive (the theme for the winter?).  The NAO continues to Pong around neutral, and the PNA generally continues to swim below the surface before coming up for air later on.  The CFS carries the theme of a cold Canada and northern half of the US with warmer than normal readings across the south and, of course, the SE, with an indication of a SE ridge.  Week Four is the only week that appears below normal in the SE.  It also shows above normal precip for the month in the SE, with Week One being the only week showing below normal.

 

Overall, I'm not too concerned with the CFS.  It's fun to talk about, but it bounces around almost daily.  What I am more concerned with is the propensity for the PNA to remain negative and the AO to remain positive.  I've also noticed that so far, the AO has been shown several times to go negative, but that seems to usually get muted or reversed as we get closer to verification.  As we've seen, it doesn't have to be the end of the world, but that combination should foster a stout SE ridge at times, especially if the -EPO/WPO breaks down.  It would really be nice to see those indexes turn around as we head into the winter...which is just 2 days away!

[Cold Rain]

December pattern still supporting fantasy storms!

 

Threat remains starting at hr 276.

 

Here is hr300 w/ 1043 High in VA. Down from a 1052 high in Minnesota. 

 

 

 

Whoever is not cold enough for snow gets hit by an ice storm. 

 

Here is Wxrisk.com's new profile picture.

 

 

 

I bet that if that huge high is sitting in that location (in VA/PA), the storm system is either going to be suppressed to oblivion or there will be more snow than indicated at this point.

[CAD_Wedge_NC]

I bet that if that huge high is sitting in that location (in VA/PA), the storm system is either going to be suppressed to oblivion or there will be more snow than indicated at this point.

 

You are 100% correct. My guess is that the high pressure will not be in that location or as strong come verification time. However, there will be a battle between the cold dense air and the southeast ridge. So, at least on paper, it is possible. In my observations of CAD events involving prolonged damaging ice storms in the piedmont, there are a few warning signs to look for:

 

1) cold source region...... -20C 850's in northern New England. This outbreak has that.....Check

2) low pressure that cuts inland from the coast or over-running...Check

3) strong high pressure in a favorable position to provide a continuous supply of cold dry air...Check

4) 925mb to surface below freezing and 850mb temps <+5C...Check

 

If the subfreezing layer is any deeper than that, then you will get mostly sleet. Keep in mind that this event is still out in La-La land so I wouldn't put much faith into it...... Now, if these warning signs are still there within 72 hours of the event, then it has to be considered.

[Cold Rain]

You are 100% correct. My guess is that the high pressure will not be in that location or as strong come verification time. However, there will be a battle between the cold dense air and the southeast ridge. So, at least on paper, it is possible. In my observations of CAD events involving prolonged damaging ice storms in the piedmont, there are a few warning signs to look for:

1) cold source region...... -20C 850's in northern New England. This outbreak has that.....Check

2) low pressure that cuts inland from the coast or over-running...Check

3) strong high pressure in a favorable position to provide a continuous supply of cold dry air...Check

4) 925mb to surface below freezing and 850mb temps <+5C...Check

If the subfreezing layer is any deeper than that, then you will get mostly sleet. Keep in mind that this event is still out in La-La land so I wouldn't put much faith into it...... Now, if these warning signs are still there within 72 hours of the event, then it has to be considered.

Good post. If this is showing up within 72 hours, the I would be sounding the alarms...if I had alarms. This would be the type of pattern that I think the models would do quite well in depicting at that time range. There is no phasing to worry about and no cold chasing moisture scenario. If this type of pattern exists 3 days out, get your shovels/generators/firewood/bread/milk handy!

[Shawn]

The 06z GFS looks a lot less of a major ZR chance (thankfully imo).  The 12z coming out is looking slighty like the GGEM so far through 240 hr.  Northern band of precip in some areas through tx,tn, etc with a little ice.

 

Either way, its too far away and I almost had a heart attack seeing what I saw last night for my area.. and I agree with the post about the heavy rates that would switch it over from ice.  Makes sense for sure after the latent heat discussions once I think about it.

 

Edit: Now the system definitely looked more GGEMish at the same time frame through the whole storm ptype wise since the 12z finished up for then.  Without looking too close, N. Miss, N LA seem to get a warning criteria.. but once again.. its not exactly a bad thing not being shown here.

[WidreMann]

I hate to keep asking, but why are we looking at 180+ GFS maps?

[Shawn]

I hate to keep asking, but why are we looking at 180+ GFS maps?

 

Most likely its not a good idea I agree.  Seems the weather may be a bit boring for a bit through here though.  Seems like a storm will happen in the first week.. looks warm.  But yeah, you're right.

[WidreMann]

Most likely its not a good idea I agree.  Seems the weather may be a bit boring for a bit through here though.  Seems like a storm will happen in the first week.. looks warm.  But yeah, you're right.

Based on the AO predictions and other unfavorable indicators, any cold/snow we get is bonus this year. Expect warm and boring and be happy with token wintry weather. No need to go looking at the super-long range models for fantasies that will just let folks down.

[Cold Rain]

Based on the AO predictions and other unfavorable indicators, any cold/snow we get is bonus this year. Expect warm and boring and be happy with token wintry weather. No need to go looking at the super-long range models for fantasies that will just let folks down.

Winter cancel.

[Shawn]

Based on the AO predictions and other unfavorable indicators, any cold/snow we get is bonus this year. Expect warm and boring and be happy with token wintry weather. No need to go looking at the super-long range models for fantasies that will just let folks down.

 

Yeah the 00z Euro Control looked horrible later on for us.  from what I can gather the ENS mean was just blah.  The cold air bleeding effect doesnt even look good imo.

[WidreMann]

Winter cancel.

We'll probably still get a decent storm at some point, but it seems unlikely for us to see one of those wall-to-wall good winters this year.

[Cold Rain]

We'll probably still get a decent storm at some point, but it seems unlikely for us to see one of those wall-to-wall good winters this year.

Yep. Definitely agree about winter as a whole. I feel like we'll get two or three decent events and a few more token ones.

[Blue_Ridge_Escarpment]

Yep. Definitely agree about winter as a whole. I feel like we'll get two or three decent events and a few more token ones.

 

Which in reality, need to take a step back and realize that we live in the south and that getting two or three decent events and a few token ones would be a very good Winter, especially for those outside of WNC; east of 77.

[kvegas-wx]

Which in reality, need to take a step back and realize that we live in the south and that getting two or three decent events and a few token ones would be a very good Winter, especially for those outside of WNC; east of 77.

Bingo. I actually prefer a warm and sunny mix in winter as long as I can see the token flakes. The thump every now and then doesnt hurt. But cool and dry for 3 months just sucks.

[Cold Rain]

Which in reality, need to take a step back and realize that we live in the south and that getting two or three decent events and a few token ones would be a very good Winter, especially for those outside of WNC; east of 77.

You got that right! I'd take it and run.

[WidreMann]

Yep. Definitely agree about winter as a whole. I feel like we'll get two or three decent events and a few more token ones.

I'm gunning for one. And honestly, if we got a nice 2-4" event that covered the roads, I'd be set for the winter.

[GaWx]

Atlanta averages 2" of snow/sleet and ~~0.40" of ZR/year. So, one decent S/IP event (say, ~0.5"+) and one token event (0.1" to 0.4") is probably about average. Atlanta gets one major S/IP (say, 3.5"+) about once every four years.

[calculus1]

I hate to keep asking, but why are we looking at 180+ GFS maps?

 

I'll give you the same answer I gave Brick:  because it's a weather board and nothing else is interesting right now.

 

Based on the AO predictions and other unfavorable indicators, any cold/snow we get is bonus this year. Expect warm and boring and be happy with token wintry weather. No need to go looking at the super-long range models for fantasies that will just let folks down.

 

If someone is let down, that's their own fault.  That is through no fault of someone posting a random map or two.  People should be in charge of their own emotions.  If a person can't handle a 180+ hour GFS storm not coming to fruition, then perhaps they need to reevaluate where they put all their hopes and dreams.

 

I'm game for any weather talk that happens to be posted.  If not, times like this would be incredibly boring.  So, please keep posting those 180+ hour GFS maps or whatever, as you long as you bring some disco with them, as several people above have done quite well.  I don't care to visit the weather board and see no recent posts because the current weather is boring and everyone is walking around on egg shells afraid to mention anything out beyond 180 hours.  Thumbs down to that.

[Cold Rain]

I'm gunning for one. And honestly, if we got a nice 2-4" event that covered the roads, I'd be set for the winter.

Then hopefully, we'll get one before the *gasp* sun angle becomes a factor.

[Cold Rain]

I'm gunning for one. And honestly, if we got a nice 2-4" event that covered the roads, I'd be set for the winter.

Then hopefully, we'll get one before the *gasp* sun angle becomes a factor.

[DixieBlizzard]

I'm gunning for one. And honestly, if we got a nice 2-4" event that covered the roads, I'd be set for the winter.

 

Going to hold you to this Widre, even if someone just down the road gets a 6" event and you only end up with 2" to 4".

[Isopycnic]

Going to hold you to this Widre, even if someone just down the road gets a 6" event and you only end up with 2" to 4".

That's what she said... 

[tarheelwx]

Can anyone comment on last night's EURO?  It looks like at 240, there's a nice hp over the lakes with CAD in place.  If precip were still on the way, I'd think the cold air might be available. 

Thanks,

TW

[BNAwx]

Can anyone comment on last night's EURO?  It looks like at 240, there's a nice hp over the lakes with CAD in place.  If precip were still on the way, I'd think the cold air might be available. 

Thanks,

TW

 

I think everyone's curled up in the fetal position after seeing the long range on today's 12z Euro.    It looked a little torchy.

 

Edit:  Not really torchy...just warmer than most would like it.

[tarheelwx]

Well, I looked at the freebies and I'd say a modest torch would be accurate. At least at 850. One flop. We'll see.

TW.

[BIG FROSTY]

I wouldn't look for much cold until at least late month, unless you go out west! I'm not saying it's going to be warm, JUST warm enough that we want see any winter precip.

[Pilotwx]

Not saying its not going to warm up. But the models have not done a good job all year and especially this past summer handling the warmer patterns that was suppose to happen. So any warm up beyond 5 days needs to cautioned.

[WidreMann]

Going to hold you to this Widre, even if someone just down the road gets a 6" event and you only end up with 2" to 4".

I still have to get the regional max for the storm. Mountains can get whatever they want, though.