January Medium/Long Range Discussion Part 2

[mappy]

1 hour ago, mdsnowlover said:

whatever

busting out the big guns with this one. 

[Bob Chill]

I'm rooting for a foot of ice followed by 40mph winds. 

[mattie g]

10 hours ago, C.A.P.E. said:

Except that la Nina was "expected" to bring us a Feb/Mar torch.

I think there were quite a few folks who thought the Nina play its hand and give us an early look at winter. I personally felt that the big Nino from last year would have a part to play in this winter's weather, if only because this Nina looked to be so feeble. I have to admit that I'm impressed with what the SE ridge has done despite the lack of a strong Nina, but if we get a more backloaded winter, it wouldn't surprise me terribly.

Now...whether I *want* a backloaded winter is another thing altogether. I've frankly grown tired of having to wait for spring the last three years. Just get sh*t brown season over with!

[WinterWxLuvr]

Deep winter coming.  

[CAPE]

1 minute ago, mattie g said:

I think there were quite a few folks who thought the Nina play its hand and give us an early look at winter. I personally felt that the big Nino from last year would have a part to play in this winter's weather, if only because this Nina looked to be so feeble. I have to admit that I'm impressed with what the SE ridge has done despite the lack of a strong Nina, but if we get a more backloaded winter, it wouldn't surprise me terribly.

Now...whether I *want* a backloaded winter is another thing altogether. I've frankly grown tired of having to wait for spring the last three years. Just get sh*t brown season over with!

Ideally I prefer to get winter weather earlier, but I have enjoyed the recent back loaded winters. Looks like we could be headed in that direction again. I got lucky here with this recent storm, and I have made the most of it. Did a great hike yesterday. Having snow in early Jan with temps well below freezing and a still low sun angle is hard to beat. That being said, I wont mind the upcoming warmer weather and rain. Having snow on the ground for 4 or 5 days with cold temps is a win around here.

[yoda]

4 hours ago, showmethesnow said:

Enough support from the EPS and the GEFS to suggest the possibility of a little snowier outcome for the weekend event especially in the northern tier. Frozen precip (snow, sleet. Fr/rain) amounts are fairly light throughout the metro regions on the EPS with roughly .1-.2" and the GEFS comes in a little better with roughly .4+". 

06z GFS is 1-3"... we buy

[mattie g]

47 minutes ago, WinterWxLuvr said:

Deep winter coming.  

It's so rare here that it's kind of cool when it does happen!

43 minutes ago, C.A.P.E. said:

Ideally I prefer to get winter weather earlier, but I have enjoyed the recent back loaded winters. Looks like we could be headed in that direction again. I got lucky here with this recent storm, and I have made the most of it. Did a great hike yesterday. Having snow in early Jan with temps well below freezing and a still low sun angle is hard to beat. That being said, I wont mind the upcoming warmer weather and rain. Having snow on the ground for 4 or 5 days with cold temps is a win around here.

I'll take my winter when I can get it, and if it means that my daughter gets to play in some snow, then bring it on! Like you, I'd much prefer it happen earlier rather than later, but beggars can't be choosers!

I'd love if we could get a more frontloaded winter around here - like a week or two leading into Christmas and then a couple weeks at the middle to end of January. Let it warm up in February and go from there. I realize that's not *really* feasible, even though 2009-2010 were pretty close (and awesome), but it's awesome to think of. Imagine something like:

Pattern shift around December 15, with some snow showers follwing a big front. Cold settles in and we get a nice little hit of around 8" on the 21st. Cold sticks around through Christmas, with a dusting between December 24-26. Pattern relaxes a few days later and we get a thaw for a few weeks. Pattern re-establishes itself around January 15 and sees three or four real chances in the next three weeks, including one overperforming clipper with high ratios. Primarily cold with the occasional milder day, with a big coastal near the end of the period. Total snow for January 15-February 5 is 22". Throw in a couple small events throughout the season (including one quick melter in early March) and we end up with a bit over 40".

Damn...I just weenied the hell out.

[CAPE]

9 minutes ago, mattie g said:

It's so rare here that it's kind of cool when it does happen!

I'll take my winter when I can get it, and if it means that my daughter gets to play in some snow, then bring it on! Like you, I'd much prefer it happen earlier rather than later, but beggars can't be choosers!

I'd love if we could get a more frontloaded winter around here - like a week or two leading into Christmas and then a couple weeks at the middle to end of January. Let it warm up in February and go from there. I realize that's not *really* feasible, even though 2009-2010 were pretty close (and awesome), but it's awesome to think of. Imagine something like:

Pattern shift around December 15, with some snow showers follwing a big front. Cold settles in and we get a nice little hit of around 8" on the 21st. Cold sticks around through Christmas, with a dusting between December 24-26. Pattern relaxes a few days later and we get a thaw for a few weeks. Pattern re-establishes itself around January 15 and sees three or four real chances in the next three weeks, including one overperforming clipper with high ratios. Primarily cold with the occasional milder day, with a big coastal near the end of the period. Total snow for January 15-February 5 is 22". Throw in a couple small events throughout the season (including one quick melter in early March) and we end up with a bit over 40".

Damn...I just weenied the hell out.

Ha its cool. Our climo is such that pre Christmas snow events are pretty rare. One reason Dec 2009 is a top 3 storm for me. That was amazing.

Going forward from here, the weeklies are hinting at a nice period maybe beginning as early as the end of Jan. The advertised look is much more Nino than Nina. Lets just hope something close to that continues to show up in the means in future runs. A pattern featuring an Aleutian low and an epo/pna ridge looks mighty tasty. There are also hints of higher heights in the NAO region, but we know how that mostly goes.

[WinterWxLuvr]

Just now, C.A.P.E. said:

Ha its cool. Our climo is such that pre Christmas snow events are pretty rare. One reason Dec 2009 is a top 3 storm for me. That was amazing.

Going forward from here, the weeklies are hinting at a nice period maybe beginning as early as the end of Jan. The advertised look is much more Nino than Nina. Lets just hope something close to that continues to show up in the means in future runs. A pattern featuring an Aleutian low and an epo/pna ridge looks mighty tasty. There are also hints of higher heights in the NAO region, but we know how that mostly goes.

Go on.  Say it.  

[CAPE]

Just now, WinterWxLuvr said:

Go on.  Say it.  

Oh I have said it plenty. Hope you haven't missed any. 

[dallen7908]

Thanks for the week 3 optimism guys.  Week 2 looks bleak. After a possibility of mixed precip early next week ... 

NAEFS long-range forecasts show 25th percentile lows (i.e., more than 3/4 of the simulations do not have lows below freezing during that period) near or above freezing for week 2

8-14 day CPC is forecasting a 80-90% chance of above normal temperatures as opposed to normal or below-normal. 

Couldn't be much worse than that. 

 

[psuhoffman]

9 minutes ago, dallen7908 said:

Thanks for the week 3 optimism guys.  Week 2 looks bleak. After a possibility of mixed precip early next week ... 

NAEFS long-range forecasts show 25th percentile lows (i.e., more than 3/4 of the simulations do not have lows below freezing during that period) near or above freezing for week 2

8-14 day CPC is forecasting a 80-90% chance of above normal temperatures as opposed to normal or below-normal. 

Couldn't be much worse than that. 

 

Week 2 is lost. Has been for a while. Not much point even wasting time on it. It's gonna torch. Enjoy the nice weather and get ready for the winter reload for feb. 

[Bob Chill]

Looking back at the late novie/early Dec period there are some similarities coming up. The warmth is another continental event due a a very efficient pac onslaught. Like we saw back in Dec, things can in fact reverse fairly quickly once the jet get shunted. 

This is just one day of about 6-7 that has the pac jet pretty much flooding all of north america:

 

Back in Dec the aleutian ridge shunted the jet up and over and cross polar flow + building cold hp in western Canada flipped the temp pattern really quick. The downside to that period was the persistence of the western trough. Cold did make it east but it was a slow process with a lot of moderation. We never really shook the western trough either.

 

Even though we are going through a rough patch, there should be a different progression out this time. Instead of an aleutian ridge/trough west, ensemble guidance is starting to show the early stages of the weeklies progression where the low heights off the west coast retrograde towards the aleutians and ridging builds (slowly) up along the west coast of the conus into BC. PSU has been doing great posts about this already so I'm not adding anything new. Just adding some easy to see panels to visualize things. Personally, I don't care if it gets pushed in time as long as it happens. 

The GEFS is more aggressive than the EPS for now but the same general idea at the same general time is being advertised. You can see by the end of the GEFS run how the jet max is no longer blasting into the conus. It's slowing out in the pac with part of it riding up and over the ridge building in BC and the other part getting shunted further and further south towards SoCal

 

 

Here's the H5 look:

 

And here's the spread. Majority show the pack jet into CA being cut off by this time and a bias towards a trough in the east:

 

 

Overall it looks like we would be back to normal by the end of 2 weeks. Even though there is a bias for a trough here, it's unlikely that our source region has recovered from the literal ocean of pac maritime air blasting during the previous week. However, "normal" in late Jan isn't a shutout pattern but there is still work to do before we start talking about a "good" pattern. 

The simple things to watch (assuming they actually happen) are how quickly the trough hugging the west coast can retro and how quickly the ridge can build in BC. 

What can happen that would be really good?

IMHO- both the EPS and GEFS are moving in a direction that can produce split flow. For those that don't know what that means, it means the jet roaring across the Pac gets split into 2 streams as heads for north america. One part rides up and over ridging along the west coast north of California and the other part comes underneath and into SoCal or northern mexico. This would be the absolute ideal situation but complete speculation and the most optimistic way to end Jan. 

Assuming the PNA and EPO ridges do actually develop, what could be bad? 

One thing we don't typically do well here with is a colder pattern where shortwaves are northern stream only with no gulf support or help from the southern branch of the pac jet. While we can still get snow it's a lot harder to get bigger storms in the MA with northern branch only systems. 

 

 

 

[Sparky]

22 hours ago, psuhoffman said:

These are the snow stats for Feb 1 on that year for BWI, IAD, and Westminster MD.  I would say these would be acceptable

 

BWI

Feb 11-12:  9"

Feb 18: 7"

Feb 28: 1.4"

March 21: 11"

March 30-31: 1.7"

IAD

Feb 11: 7"

Feb 18: 5"

Feb 28: 2.3"

March 21: 2.3"

March 30-21: 7"

Westminster 

Feb 1: 1"

Feb 11: 9"

Feb 16: 2"

Feb 18: 15"

Feb 28: 5"

March 13: 2"

March 21: 15"

March 30-31: 2"

Jesus, Westminster was nuked.

[CAPE]

31 minutes ago, dallen7908 said:

Thanks for the week 3 optimism guys.  Week 2 looks bleak. After a possibility of mixed precip early next week ... 

NAEFS long-range forecasts show 25th percentile lows (i.e., more than 3/4 of the simulations do not have lows below freezing during that period) near or above freezing for week 2

8-14 day CPC is forecasting a 80-90% chance of above normal temperatures as opposed to normal or below-normal. 

Couldn't be much worse than that. 

 

Late in the weekend could be a sneaky period. Cold front stalled to the south with  waves riding along it. Key is going to be strength and position of the High Pressure to the north. Its been pretty impressive on some guidance.

[midatlanticweather]

Thank you @Bob Chill for the excellent write-up! 

Yes, I can dream what the split flow could do! Hoping to have a continued better very long term look!

 

[PivotPoint]

 

Quote

Looking back at the late novie/early Dec period there are some similarities coming up. The warmth is another continental event due a a very efficient pac onslaught. Like we saw back in Dec, things can in fact reverse fairly quickly once the jet get shunted. 

This is just one day of about 6-7 that has the pac jet pretty much flooding all of north america:

 

 

Back in Dec the aleutian ridge shunted the jet up and over and cross polar flow + building cold hp in western Canada flipped the temp pattern really quick. The downside to that period was the persistence of the western trough. Cold did make it east but it was a slow process with a lot of moderation. We never really shook the western trough either.

 

Even though we are going through a rough patch, there should be a different progression out this time. Instead of an aleutian ridge/trough west, ensemble guidance is starting to show the early stages of the weeklies progression where the low heights off the west coast retrograde towards the aleutians and ridging builds (slowly) up along the west coast of the conus into BC. PSU has been doing great posts about this already so I'm not adding anything new. Just adding some easy to see panels to visualize things. Personally, I don't care if it gets pushed in time as long as it happens. 

The GEFS is more aggressive than the EPS for now but the same general idea at the same general time is being advertised. You can see by the end of the GEFS run how the jet max is no longer blasting into the conus. It's slowing out in the pac with part of it riding up and over the ridge building in BC and the other part getting shunted further and further south towards SoCal

 

 

 

Here's the H5 look:

 

 

And here's the spread. Majority show the pack jet into CA being cut off by this time and a bias towards a trough in the east:

 

 

 

Overall it looks like we would be back to normal by the end of 2 weeks. Even though there is a bias for a trough here, it's unlikely that our source region has recovered from the literal ocean of pac maritime air blasting during the previous week. However, "normal" in late Jan isn't a shutout pattern but there is still work to do before we start talking about a "good" pattern. 

The simple things to watch (assuming they actually happen) are how quickly the trough hugging the west coast can retro and how quickly the ridge can build in BC. 

What can happen that would be really good?

IMHO- both the EPS and GEFS are moving in a direction that can produce split flow. For those that don't know what that means, it means the jet roaring across the Pac gets split into 2 streams as heads for north america. One part rides up and over ridging along the west coast north of California and the other part comes underneath and into SoCal or northern mexico. This would be the absolute ideal situation but complete speculation and the most optimistic way to end Jan. 

Assuming the PNA and EPO ridges do actually develop, what could be bad? 

One thing we don't typically do well here with is a colder pattern where shortwaves are northern stream only with no gulf support or help from the southern branch of the pac jet. While we can still get snow it's a lot harder to get bigger storms in the MA with northern branch only systems. 

Good post.

From what I remember split flow is less predominant in Nina/neutral years? It would be great getting that feature going into latter half of jan/early feb.

Can disruption/breaking of that strong looking polar vortex buckle the pacific flow -- As in helping contribute to a split flow?

 

[Ginx snewx]

27 minutes ago, Bob Chill said:

Looking back at the late novie/early Dec period there are some similarities coming up. The warmth is another continental event due a a very efficient pac onslaught. Like we saw back in Dec, things can in fact reverse fairly quickly once the jet get shunted. 

This is just one day of about 6-7 that has the pac jet pretty much flooding all of north america:

 

Back in Dec the aleutian ridge shunted the jet up and over and cross polar flow + building cold hp in western Canada flipped the temp pattern really quick. The downside to that period was the persistence of the western trough. Cold did make it east but it was a slow process with a lot of moderation. We never really shook the western trough either.

 

Even though we are going through a rough patch, there should be a different progression out this time. Instead of an aleutian ridge/trough west, ensemble guidance is starting to show the early stages of the weeklies progression where the low heights off the west coast retrograde towards the aleutians and ridging builds (slowly) up along the west coast of the conus into BC. PSU has been doing great posts about this already so I'm not adding anything new. Just adding some easy to see panels to visualize things. Personally, I don't care if it gets pushed in time as long as it happens. 

The GEFS is more aggressive than the EPS for now but the same general idea at the same general time is being advertised. You can see by the end of the GEFS run how the jet max is no longer blasting into the conus. It's slowing out in the pac with part of it riding up and over the ridge building in BC and the other part getting shunted further and further south towards SoCal

 

 

Here's the H5 look:

 

And here's the spread. Majority show the pack jet into CA being cut off by this time and a bias towards a trough in the east:

 

 

Overall it looks like we would be back to normal by the end of 2 weeks. Even though there is a bias for a trough here, it's unlikely that our source region has recovered from the literal ocean of pac maritime air blasting during the previous week. However, "normal" in late Jan isn't a shutout pattern but there is still work to do before we start talking about a "good" pattern. 

The simple things to watch (assuming they actually happen) are how quickly the trough hugging the west coast can retro and how quickly the ridge can build in BC. 

What can happen that would be really good?

IMHO- both the EPS and GEFS are moving in a direction that can produce split flow. For those that don't know what that means, it means the jet roaring across the Pac gets split into 2 streams as heads for north america. One part rides up and over ridging along the west coast north of California and the other part comes underneath and into SoCal or northern mexico. This would be the absolute ideal situation but complete speculation and the most optimistic way to end Jan. 

Assuming the PNA and EPO ridges do actually develop, what could be bad? 

One thing we don't typically do well here with is a colder pattern where shortwaves are northern stream only with no gulf support or help from the southern branch of the pac jet. While we can still get snow it's a lot harder to get bigger storms in the MA with northern branch only systems. 

 

 

 

Nice job Bobby

[WinterWxLuvr]

Good post Bob.

[WinterWxLuvr]

I'm really curious as to how the weekend shakes out.  Potential for a mess is there it would seem to me.

[Bob Chill]

10 minutes ago, midatlanticweather said:

Thank you @Bob Chill for the excellent write-up! 

Yes, I can dream what the split flow could do! Hoping to have a continued better very long term look!

 

We have a long way to go before taking anything seriously but we can dream right? lol

The other thing to consider is that no pattern has locked in this winter more than a couple weeks. I posted about that before winter started. That no obvious signals going into the season pointed in any specific direction and that variability would be the theme. Seems like a good call so far. One of the reasons that I went low in the snowfall contest and expected a sub climo snow winter was because of this. Highly variable winters usually don't reward boom or bust climo locations. We need a lot of chances and a 1-2 bigger storms to hit climo. That's hard to come by without extended good periods. Assuming we do get another decent pattern, how long does it last? My money is not the whole month of Feb. Probably half but just a guess. 

5 minutes ago, PivotPoint said:

 

Good post.

From what I remember split flow is less predominant in Nina/neutral years? It would be great getting that feature going into latter half of jan/early feb.

Can disruption/breaking of that strong looking polar vortex buckle the pacific flow -- As in helping contribute to a split flow?

 

Are you asking about the strat pv or pv in the troposphere?

[Bob Chill]

5 minutes ago, WinterWxLuvr said:

I'm really curious as to how the weekend shakes out.  Potential for a mess is there it would seem to me.

Your area and folks like PSU, mappy, etc are in much better spots for most of us. Temps will be borderline near the cities from how it looks right now and timing isn't the best with most of the precip falling during the daytime on Sat. 

Last night's euro was one of the more icy runs of late though with even a little snow to start. Temps hover around 30 for most folks during the day on Sat but being a daytime event with temps near 30 usually means ice will look pretty on trees and stuff but roads would be just wet.  

[WxUSAF]

16 minutes ago, WinterWxLuvr said:

I'm really curious as to how the weekend shakes out.  Potential for a mess is there it would seem to me.

Pretty big trend to weaken the arctic high over the last 2 days in the GFS. 12z run on the 8th had a 1049mb high. Today's is 1036. Can't seem that being good in any way.

[Bob Chill]

24 minutes ago, Ginx snewx said:

Nice job Bobby

Thanks Ginx. I should have no problem quadrippling my snowfall on the year. Sitting at a stout 1.3" so far!

[PivotPoint]

17 minutes ago, Bob Chill said:

We have a long way to go before taking anything seriously but we can dream right? lol

The other thing to consider is that no pattern has locked in this winter more than a couple weeks. I posted about that before winter started. That no obvious signals going into the season pointed in any specific direction and that variability would be the theme. Seems like a good call so far. One of the reasons that I went low in the snowfall contest and expected a sub climo snow winter was because of this. Highly variable winters usually don't reward boom or bust climo locations. We need a lot of chances and a 1-2 bigger storms to hit climo. That's hard to come by without extended good periods. Assuming we do get another decent pattern, how long does it last? My money is not the whole month of Feb. Probably half but just a guess. 

Are you asking about the strat pv or pv in the troposphere?

Troposphere.. I don't think strat warming would directly affect lower atmosphere weather like jet flow, correct?

[BristowWx]

Maybe if it had time to wedge further.  But even a little frozen is good to me. MD should do well as Bob said.  

[Amped]

4 minutes ago, WxUSAF said:

Pretty big trend to weaken the arctic high over the last 2 days in the GFS. 12z run on the 8th had a 1049mb high. Today's is 1036. Can't seem that being good in any way.

It is showing more precip with the first wave which has the best chance for frozen. The second wave hasn't had a chance in a long time.

[RichmondTarHeel]

I fly out of IAD at 5:00pm on Sunday headed for Ireland.  I hope for good weather, but at 5:01pm I hope you guys get nuked with snow.  I'm actually starting to worry, because when I want snow, we don't get it, but when I don't want it, we get nuked (I had travel plans last year the weekend of the blizzard that had to be cancelled, too). 

[psuhoffman]

1 hour ago, Bob Chill said:

We have a long way to go before taking anything seriously but we can dream right? lol

The other thing to consider is that no pattern has locked in this winter more than a couple weeks. I posted about that before winter started. That no obvious signals going into the season pointed in any specific direction and that variability would be the theme. Seems like a good call so far. One of the reasons that I went low in the snowfall contest and expected a sub climo snow winter was because of this. Highly variable winters usually don't reward boom or bust climo locations. We need a lot of chances and a 1-2 bigger storms to hit climo. That's hard to come by without extended good periods. Assuming we do get another decent pattern, how long does it last? My money is not the whole month of Feb. Probably half but just a guess. 

Are you asking about the strat pv or pv in the troposphere?

Good call on the variability.  One thing that could help us hold a snow friendly period a bit longer in February would be if we actually get a PNA ridge and trough axis in the east.  While things have been variable for sure, our other problem is the way the patterns have set up we have been on the edge of everything even during the colder phases.  So we have in effect wasted a week or more of the cold periods just waiting for things to evolve to a peak period when we were in the game before the whole thing collapsed again.  If whatever comes next sets up in the east we could find ourselves in a 2-3 week favorable period instead of one week, then only needing a one week reload before one last round come March instead of 2-3 weeks.  That would be our best case scenaro as I agree nothing is likely to lock in right through the rest of winter, but if we could get a window of opportunity Feb 1-14 during peak climo, then perhaps another Feb 24-March 10 to end the season (these are just WAG examples) and score one decent hit both periods would most of us really complain?  If we are only going to get one really good look February is when I want it to be. 

[Bob Chill]

1 hour ago, PivotPoint said:

Troposphere.. I don't think strat warming would directly affect lower atmosphere weather like jet flow, correct?

Yea, strat stuff is always a bit of voodoo even though there is certainly solid science backing up the various effects of the strat PV.

 Sometimes there's a complete disconnect, other times a disturbed vortex has direct postive effects (Jan-Feb 2014 is a good example), and then there can be true SSW events that do nothing except make europe cold. A blue monster is always a problem though. The last 3 years seem to be a blue monster cycle. This year isn't so bad but the recent consolidation and strengthening surely didn't help us. 

The nasty vortex of AK is the core issue we're facing coming up. All we really need to get things going again is that vortex/low height anomaly to move southwest under the aleutians and it would make a word of difference. It's a small shift in the global circ but would have profound effects in the eastern conus.