Miller A/B/Hybrid

[psuhoffman]

@Maestrobjwa hope this helps. 
 

There is some debate about what is a B v A/B Hybrid or even between A v B and I do not claim these definitions to be any definitive authority. Just trying to explain and have no interest in that debate.  Here I will describe each then in the next post I’ll explain why some work better then others  

Miller A is simple, a pure southern stream system that originated near the gulf coast and comes up the east coast. 

A pure Miller B is a northern stream system that transfers its energy (jumps) to the coast. The jump often happens due to the system meeting resistance as it approaches the Apps and CAD and so it jumps to the baroclinic zone along the coast. Path of least resistance and it this case simply transferring energy and redeveloping.
 
Hybrids can come in 2 versions.  One version is a northern stream system that dives in and phases or transfers energy to a southern stream wave along the east coast.
 
A second version is a southern stream wave that initially tracks north into the TN or OH valley before jumping to the coast  

 

 

[Ji]

we have 3 ways to win out of 4 but it seems like we get Miller B'd the most

[psuhoffman]

The thing is we need a storm to track to our southeast.  And it needs to be mature enough as it passes our latitude to have developed a healthy CCB to have deep moisture transport into the cold sector to the NW of the track. 

how the storm gets to that spot isn’t really as important as that it does. That it passes somewhere near the NC coast to VA beach moving northeast and that it’s mature with a healthy CCB to transport moisture west to the north of the low by that latitude. 
 

Problem is it’s obviously easier to do that the further south the storm initiates. So a gulf system is our best bet. The miller b V2, assuming the transfer happens before it gets north of about TN/KY can be just as good if not better then a miller A. Less chance it misses to the east.  But it really doesn’t matter what type the storm is so long as it ends up on the coast to our southeast. Problem with pure Miller B systems is it’s really hard to get a pure NS wave to get far enough south for that to happen. Usually unless there is a STJ wave to phase with a NS system will just jump to the coast at about its latitude which is typically too far north. I don’t get stuck on the A/B thing. Really the issue is just the storm tracked too far north.  
 

here are some examples though of a hybrid v1 and a pure miller B that did work for our area. 
 

Feb 10-11 2010 was a miller b hybrid v1. 

the northern stream system over OH phased with the weaker STJ system off the southeast coast but the transfer happened far enough south to develop the CCB in time for MD.  
 

Jan 22 2005 was a pure miller B that dropped 4-8” across most of MD and that’s honestly about the best we can expect from that type of system.  It was a nice event if we ignore the 2 feet New England got lol  

 

 

[psuhoffman]

23 minutes ago, Ji said:

we have 3 ways to win out of 4 but it seems like we get Miller B'd the most

Yea well those are types of coastals. It leaves out all the tracks that don’t even become coastals. Or all the examples where the track was fine but we had no cold!  Bottom line is we are too far south. We are south of the mean polar jet storm track.  We need an anomaly to get snow! 

[Ji]

2 minutes ago, psuhoffman said:

The thing is we need a storm to track to our southeast.  And it needs to be mature enough as it passes out latitude to have developed a healthy CCB to have deep moisture transport into the cold sector to the NW of the track. 

how the storm gets to that spot isn’t really as important as that it does. That it passes somewhere near the NC coast to VA beach moving northeast and that it’s mature with a healthy CCB to transport moisture west to the north of the low by that latitude. 
 

Problem is it’s obviously easier to do that the further south the storm initiates. So a gulf system is our best bet. The miller b V2, assuming the transfer happens before it gets north of about TN/KY can be just as good if not better then a mullet B. Less chance it misses to the east.  But it really doesn’t matter what type the storm is so long as it ends up on the coast to our southeast. Problem with pure Miller B systems is it’s really hard to get a pure NS wave to get far enough south for that to happen. Usually unless there is a STJ wave to phase with a NS system will just jump to the coast at about its latitude which is typically too far north. I don’t get stuck on the A/B thing. Really the issue is just the storm tracked too far north.  
 

here are some examples though of a hybrid v1 and a pure miller B that did work for our area. 
 

Feb 10-11 2010 was a miller b hybrid v1. 

the northern stream system over OH phased with the weaker STJ system off the southeast coast but the transfer happened far enough south to develop the CCB in time for MD.  
 

Jan 22 2005 was a pure miller B that dropped 4-8” across most of MD and that’s honestly about the best we can expect from that type of system.  It was a nice event if we ignore the 2 feet New England got lol  

 

 

jan 2005 was another storm that had Richmond/DC as the bullseye a few days before the event. That was an awful event considering we were getting 20 plus inch outputs 3-4 days out

[WinterWxLuvr]

9 hours ago, psuhoffman said:

@Maestrobjwa hope this helps. 
 

There is some debate about what is a B v A/B Hybrid or even between A v B and I do not claim these definitions to be any definitive authority. Just trying to explain and have no interest in that debate.  Here I will describe each then in the next post I’ll explain why some work better then others  

Miller A is simple, a pure southern stream system that originated near the gulf coast and comes up the east coast. 

A pure Miller B is a northern stream system that transfers its energy (jumps) to the coast. The jump often happens due to the system meeting resistance as it approaches the Apps and CAD and so it jumps to the baroclinic zone along the coast. Path of least resistance and it this case simply transferring energy and redeveloping.
 
Hybrids can come in 2 versions.  One version is a northern stream system that dives in and phases or transfers energy to a southern stream wave along the east coast.
 
A second version is a southern stream wave that initially tracks north into the TN or OH valley before jumping to the coast  

 

 

I tend to like B v2 above all. Just curious as to what PDII, Feb 6, 2010, and Jan 2016 were

[psuhoffman]

10 hours ago, Ji said:

jan 2005 was another storm that had Richmond/DC as the bullseye a few days before the event. That was an awful event considering we were getting 20 plus inch outputs 3-4 days out

From 4-5 days out the guidance had a healthy STJ wave and it was a hybrid system. About 3 days out all guidance lost that wave. Kind of similar to what happened in Dec 2017. Only there was a vigorous enough NS wave and far enough south due to blocking that we still managed a decent snow. But as soon as the STJ crapped out the bigger options were gone.  I remember some were in denial about that though. But 2-4” across N VA and 4-8” across MD is honestly a GREAT result for a pure miller b.  Usually they miss us completely. And most times it’s not even close. I know we obsess over those rare times one gets Philly and screws us but most Miller Bs miss Philly to the northeast also and some even are too late for NYC. We don’t even think of all those because they don’t tease us by being tantalizingly close.  

[psuhoffman]

1 hour ago, WinterWxLuvr said:

I tend to like B v2 above all. Just curious as to what PDII, Feb 6, 2010, and Jan 2016 were

I totally agree (by the definitions above) hybrid v2 is our best options. But here is where that gets complicated. First some argue over these definitions. Some think hybrid v2 are miller A. I have no dog in that fight. I really don’t care what we call things. It’s just annoying to have multiple classifications floating around confusing discussions.  The second issue is that’s very location specific. If your NW of 95 hybrid v2 are the best storms. If you’re east of 95 miller As are. We obsess over Miller A storms but they can sometimes miss us to the east. 
 

PD2 had a primary up into TN then jump to VA capes. Feb 6 2010 was pure STJ wave but had a double barrel structure with one low up to KY and other up the coast.  2016 was pure STJ but the primary went from LA to near ATL then jumped to off SC. That one is iffy. That’s a pretty minor jump and so far south I would tend to lean Miller A, albeit a more inland initially miller A. It’s borderline (by my definitions). Judgement call. And again I don’t care lol. It snowed. That’s what I care about. People can call it Mickey Mouse for all I care. The other 2 were clearly hybrids (by these definitions). 

[WinterWxLuvr]

4 minutes ago, psuhoffman said:

I totally agree (by the definitions above) hybrid v2 is our best options. But here is where that gets complicated. First some argue over these definitions. Some think hybrid v2 are miller A. I have no dog in that fight. I really don’t care what we call things. It’s just annoying to have multiple classifications floating around confusing discussions.  The second issue is that’s very location specific. If your NW of 95 hybrid v2 are the best storms. If you’re east of 95 miller As are. We obsess over Miller A storms but they can sometimes miss us to the east. 
 

PD2 had a primary up into TN then jump to VA capes. Feb 6 2010 was pure STJ wave but had a double barrel structure with one low up to KY and other up the coast.  2016 was pure STJ but the primary went from LA to near ATL then jumped to off SC. That one is iffy. That’s a pretty minor jump and so far south I would tend to lean Miller A, albeit a more inland initially miller A. It’s borderline (by my definitions). Judgement call. And again I don’t care lol. It snowed. That’s what I care about. People can call it Mickey Mouse for all I care. The other 2 were clearly hybrids (by these definitions). 

Thanks. That’s what my memory said about the first two but I couldn’t remember about 2016

[Cobalt]

2 hours ago, psuhoffman said:

From 4-5 days out the guidance had a healthy STJ wave and it was a hybrid system. About 3 days out all guidance lost that wave. Kind of similar to what happened in Dec 2017. Only there was a vigorous enough NS wave and far enough south due to blocking that we still managed a decent snow. But as soon as the STJ crapped out the bigger options were gone.  I remember some were in denial about that though. But 2-4” across N VA and 4-8” across MD is honestly a GREAT result for a pure miller b.  Usually they miss us completely. And most times it’s not even close. I know we obsess over those rare times one gets Philly and screws us but most Miller Bs miss Philly to the northeast also and some even are too late for NYC. We don’t even think of all those because they don’t tease us by being tantalizingly close.  

I feel like I remember hearing somewhere that March 5 2013 was a Miller B. Is this thinking correct? I know areas near Richmond got a WSW level event and of course out near the Shenandoah area they got double digit snowfalls. Would the track being farther to the south suggest that it was more of a hybrid?

[MDstorm]

Great thread, PSU!

PD1(1979) looks like a supercharged Hybrid V1 as the Ohio Valley trough “dove in” and ignited the southern storm.   I vaguely remember Accuweather having the best handle on this storm from 12-24 hours out as NWS busted big time.  Below are 2 good write ups on that storm.

https://journals.ametsoc.org/view/journals/mwre/109/7/1520-0493_1981_109_1542_tpdsof_2_0_co_2.xml?tab_body=pdf

https://ocean.weather.gov/2-PresidentsDayStormColloquium_Uccellini.pdf

[psuhoffman]

1 hour ago, Cobalt said:

I feel like I remember hearing somewhere that March 5 2013 was a Miller B. Is this thinking correct? I know areas near Richmond got a WSW level event and of course out near the Shenandoah area they got double digit snowfalls. Would the track being farther to the south suggest that it was more of a hybrid?

Yes but it was March with a crazy block. NS system dove straight SE right to the coast and stalled...then redeveloped northeast a day later. Crazy stuff like that can happen in March with blocking. 

[Amped]

I really never thought the MillerA/B  was a good way to characterize a storm.

I think his intent was to characterize zonal ULL with W-E moving systems as Miller B, and amped up full latitude troffs with  S-N moving systems as Miller A.

 

However,  whether the initial surface low forms in the TN/OH Valley or  along the east coast is determined by the locations of fronts, CAD, moisture and small scale disturbances within the troff, or just ahead of it.

Sometimes both develop simultaneously like February 2010.   Sometime there is one low directly over the  SC/NC mountains like Feb 2006, kind of both a primary and a coastal..   

 

Also storms can turn right or left as they track up the coast depending on amplification timing and confluence ahead of the storm.

 

So in summary I consider the Miller A/B a sometimes difficult to make distinction that doesn't tell us much about what the storms going to bring unless it happens to be one of the few that fits well into one category..   .   

 

 

 

 

 

 

[Maestrobjwa]

Thanks for the write-up @psuhoffman! A good reference to have..So essentially, I gather from this is that pure Miller B's are kinda heartbreakers that either screw us completely or, at best, give us a small-moderate amount while dumping more further north/northeast? Could we say, then...that the next time we have a modeled pure Miller B, it's better to look at it as low probability? (no matter what the op depictions are, lol)

The southern system part makes sense...I can see STJ involvement is kind of our bread and butter isn't it?

[psuhoffman]

1 minute ago, Maestrobjwa said:

Thanks for the write-up @psuhoffman! A good reference to have..So essentially, I gather from this is that pure Miller B's are kinda heartbreakers that either screw us completely or, at best, give us a small-moderate amount while dumping more further north/northeast? Could we say, then...that the next time we have a modeled pure Miller B, it's better to look at it as low probability? (no matter what the op depictions are, lol)

The southern system part makes sense...I can see STJ involvement is kind of our bread and butter isn't it?

Yes but again it’s not the type that matters. It’s the track. Problem with an all northern stream system is it’s difficult to get them to track far enough south. Actually when they do track far enough south they are dry and just clippers because typically a system diving southeast isn’t amplifying and a NS system diving south in a northerly flow is cut off from any deep moisture source until it hits the Atlantic and that’s too late for us. Amplifying storms usually are lifting poleward.  So to get a NS system to bottom out and begin to amplify/lift north and still stay under us is really hard. We are just too far south for that normally. 

[uncletim]

Thanks for taking the time for a great write-up, as always. Somehow I remember a lot of suspense here in the wee hours of 2/10/10 waiting for the pressure to dive off the VA capes, which  made me think it was the rare pure B that worked out. The specific reference to that one is a welcome clarification.

[WxMan1]

I did a bit of research on the topic a few years back. It was quite an illuminating experience!

Miller_Cyclogenesis_Classification_US_Atlantic_Coastal_Region.pdf

[mattie g]

Is it me, or do northern stream storms tend to bomb out a lot more/more quickly than do any of the others? Is this just because storms have the chance to deepen more as they reach New England or is there something in the physics that causes it to happen? I ask especially because the 2/10/10 storm was pretty ferocious - much more so than most of our snowstorms.

[MillvilleWx]

9 hours ago, mattie g said:

Is it me, or do northern stream storms tend to bomb out a lot more/more quickly than do any of the others? Is this just because storms have the chance to deepen more as they reach New England or is there something in the physics that causes it to happen? I ask especially because the 2/10/10 storm was pretty ferocious - much more so than most of our snowstorms.

I think it has something to do with the energy at hand. A northern stream system that has significant wave amplitude will begin with more energy and the colder air involved might add to the baroclinicity factor, especially once near the coast. That's just my proxy on that. I'll see if I can find any articles that pertain to the theory.