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January 28-29, 2022 Miller abcdefu Storm Threat


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I didn't want to post this earlier when there was still a lot of hope and guidance was coming in but some thoughts I've had watching the "tracking" unfold for this event.  

1) Know the bias of the guidance for the situation.  The euro and NAM have a known bias to over amplify systems and phase too quickly in NS/SS phase situations.  So seeing them as the only guidance the last 48 hours that was REALLY good...shouldn't have really excited much.  If something is real it should show up on guidance other then the one that ALWAYS shows that because of a bias. 

2) Don't fall prey to our own bias to look for positives and dismiss negatives.  Example:  if the NAM has a great run at 0z, then an awful one at 6z, then at 12z it trends better than 6z but not quite back to 0z...thats not a "good trend".  That means the NAM is just bouncing around within a range of options and overall we are no better off then 12 hours ago. 

Likewise for an entire suite of guidance.  If the ICON was the furthest east and shifts west...that isn't a west trend.  Its the ICON coming in line with consensus.  If the euro was great and has a bad run...then the GFS trends better...we didnt actually gain any ground.  Models are just shifting around within their envelope of likely outcomes.  In the end of the suite we were still on the NW fringes of all possible outcomes in terms of significant snowfall.  We needed the most extreme NW members of all model runs for each suite, including ensembles, to be correct to get a big snowstorm.  Just because there would be one or two pieces of guidance that spit out that solution didnt ever make it the likely outcome.  

3) There is no guarantee a "trend" will continue.  I am NOT going to argue what a trend is.  Call it what you want.  I don't care.  But when someone says "its still a miss but its heading the right way" I cringe inside.  No its not.  It's not heading anywhere.  It's just one simulation based on the current data available.  The next run could easily get worse.  But if something got better some people seem to set the expectation that it will continue the same "trend" the following run.  That sets us up for disappointment.  

4) Inside 100 hours HUGE shifts in our favor become a lot less likely.  Outside 100 hours we see major synoptic changes all the time.  But once inside 100 hours the guidance has been really good, if you ignore a random fluke outliers and focus on the consensus each run, with the general setup.    A lot of these situations lately we are taking very unfavorable synoptic setups inside 100 hours  and trying to will the storm into what we want.  I'm doing it too!  But when we get these minor changes in a model that get it closer to a snowstorm for us...the odds are never that those improvements will continue run after run until its a snow for us.  Odds are it was just a minor permutation and the next run is just as likely to shift back the other way because there is a reason its still a miss and is a miss on the preponderance of evidence...the synoptic setup likely isn't right in some way.  I think the days of us saying "thats right where I want it" once its inside 100 hours are over.  You know where I want it at 80 hours now....over us.  This willing it north or south or west just fail's 90% of the time.  The models have become a lot better.  That doesn't mean we dont still see details ironed out.  There will be changes to details.  And sometimes...there can still be a true bust where some factor is not handled right and a storm shifts...but its going to be the vast minority of the time not the majority.  We dont' want a storm 200 miles away in any direction inside 5 days out anymore.  Truth is the storms end up pretty close to what the guidance shows once they start to converge on a general idea usually around 100 hours out lately most of the time.  

5) big amped up phased storms are a lot of fun to track but not our best bet for snow in a progressive pattern.  Boundary waves are the best bet to get snow here without blocking.  Unfortunately we are getting a reminder in how frustrating a pacific driven cold pattern without Atlantic blocking can be.  Truth is if we want a high probability of a big snowstorm we need BOTH.  But we can definitely score waves moving west to east along a boundary in a gradient type pattern without blocking.  Just need luck with wave spacing.  

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I’m honestly interested in the PRE that LWX mentions in their AFD. Pete Mullinax also refers to this in his twitter thread; the possibility of enhanced snowfall / banding in our area from the NS wave. It appears the NS wave overperforming is many of our best shot to see appreciable snowfall at this point, except for CAPE’s area. 

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4 minutes ago, psuhoffman said:

I didn't want to post this earlier when there was still a lot of hope and guidance was coming in but some thoughts I've had watching the "tracking" unfold for this event.  

1) Know the bias of the guidance for the situation.  The euro and NAM have a known bias to over amplify systems and phase too quickly in NS/SS phase situations.  So seeing them as the only guidance the last 48 hours that was REALLY good...shouldn't have really excited much.  If something is real it should show up on guidance other then the one that ALWAYS shows that because of a bias. 

2) Don't fall prey to our own bias to look for positives and dismiss negatives.  Example:  if the NAM has a great run at 0z, then an awful one at 6z, then at 12z it trends better than 6z but not quite back to 0z...thats not a "good trend".  That means the NAM is just bouncing around within a range of options and overall we are no better off then 12 hours ago. 

Likewise for an entire suite of guidance.  If the ICON was the furthest east and shifts west...that isn't a west trend.  Its the ICON coming in line with consensus.  If the euro was great and has a bad run...then the GFS trends better...we didnt actually gain any ground.  Models are just shifting around within their envelope of likely outcomes.  In the end of the suite we were still on the NW fringes of all possible outcomes in terms of significant snowfall.  We needed the most extreme NW members of all model runs for each suite, including ensembles, to be correct to get a big snowstorm.  Just because there would be one or two pieces of guidance that spit out that solution didnt ever make it the likely outcome.  

3) There is no guarantee a "trend" will continue.  I am NOT going to argue what a trend is.  Call it what you want.  I don't care.  But when someone says "its still a miss but its heading the right way" I cringe inside.  No its not.  It's not heading anywhere.  It's just one simulation based on the current data available.  The next run could easily get worse.  But if something got better some people seem to set the expectation that it will continue the same "trend" the following run.  That sets us up for disappointment.  

4) Inside 100 hours HUGE shifts in our favor become a lot less likely.  Outside 100 hours we see major synoptic changes all the time.  But once inside 100 hours the guidance has been really good, if you ignore a random fluke outliers and focus on the consensus each run, with the general setup.    A lot of these situations lately we are taking very unfavorable synoptic setups inside 100 hours  and trying to will the storm into what we want.  I'm doing it too!  But when we get these minor changes in a model that get it closer to a snowstorm for us...the odds are never that those improvements will continue run after run until its a snow for us.  Odds are it was just a minor permutation and the next run is just as likely to shift back the other way because there is a reason its still a miss and is a miss on the preponderance of evidence...the synoptic setup likely isn't right in some way.  I think the days of us saying "thats right where I want it" once its inside 100 hours are over.  You know where I want it at 80 hours now....over us.  This willing it north or south or west just fail's 90% of the time.  The models have become a lot better.  That doesn't mean we dont still see details ironed out.  There will be changes to details.  And sometimes...there can still be a true bust where some factor is not handled right and a storm shifts...but its going to be the vast minority of the time not the majority.  We dont' want a storm 200 miles away in any direction inside 5 days out anymore.  Truth is the storms end up pretty close to what the guidance shows once they start to converge on a general idea usually around 100 hours out lately most of the time.  

5) big amped up phased storms are a lot of fun to track but not our best bet for snow in a progressive pattern.  Boundary waves are the best bet to get snow here without blocking.  Unfortunately we are getting a reminder in how frustrating a pacific driven cold pattern without Atlantic blocking can be.  Truth is if we want a high probability of a big snowstorm we need BOTH.  But we can definitely score waves moving west to east along a boundary in a gradient type pattern without blocking.  Just need luck with wave spacing.  

I said this yesterday, got grilled. Glad someone more articulate can make better sense than me. Thank you.

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On 1/25/2022 at 12:04 PM, leesburg 04 said:

Every shift nails the same locations while the fringe areas stay relatively consistent. I'm no expert but I do have to pay attention to trends and details in my work and what I notice is despite all of the shifts and changes at any hour the end results aren't changing drastically so to me that says we probably have seen something close to the final solution save a few tweaks. Again, hope i'm wrong but if my area gets 2-4" that will cover everything and look gorgeous and I can be happy with that.

This

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5 minutes ago, jayyy said:

I’m honestly interested in the PRE that LWX mentions in their AFD. Pete Mullinax also refers to this in his twitter thread; the possibility of enhanced snowfall / banding in our area from the NS wave. It appears the NS wave overperforming is many of our best shot to see appreciable snowfall at this point, except for CAPE’s area. 

We just need it not to go way south like the NAMs/ICON just did...

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3 minutes ago, jayyy said:

Stage 5 meltdown in progress in the NE forum. Oof. NAM Euro ICON and RGEM all whiffed after showing 1-3 feet for days. That’s rough.  

euro is showing 37 inches for boston. Why you spreading fake news?

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5 minutes ago, jlewis1111 said:

euro is showing 37 inches for boston. Why you spreading fake news?

My apologies. So… one model (with a known bias to overdo phasing and the western flank of coastals) as the rest lost 1-2 feet of digital snow. Not much better :/

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