I dont care anymore....I am starting a storm thread for March 20-21. Got nothing to lose.

[Ralph Wiggum]

Wiggum is out of his mind if he is debbing this run. Ggem still south with wave 2. This is fine so far. He is in some kind of bizarro world, he was positive last week when the ship was sinking and now he is "bailing water" with an imaginary bucket from a dry deck. 

Not debbing 'this run'...if I came off that way then poor communication on my part. I have been cautioned about following op runs verbatim, so I am cautiously trying not to look at the gfs like a hungry fish looks at a piece of bait. What I am saying is yes, the looks overall so far at 12z verbatim, especially blended, look really good. What I dont like is how this is now a 2, even a 3 part deal where each stage relies on the previous energy. This can all come together as a MECS/HECS DC->BOS, no doubt and there is growing support for that. Again, what I am not a huge fan of is breaking this into pieces hoping many different keys fall into proper place, proper spacing, proper timing. A storm delayed can be a storm denied but I would certainly take that gfs verbatim. Im fairly certain tho we r on the same page irt knowing this will not be the final outcome. Ive seen some shifting around of energies in the NS past few suites to warrant caution still. Again, my apologies if I came off as being over pessimistic.

[ErinInTheSky]

12 minutes ago, WxUSAF said:

Trying to figure out how this fails and I think I have it. Front running wave goes north and rains on us and then tail end low develops too far south and then loops around to crush Boston. Lock it up folks.

I don't know, my fail mode is ptype issues with the first wave and then the second one reforming quite a bit north/northeast.

[osfan24]

1 minute ago, supernovasky said:

Got here late December 2016.

Oh man. I don't know why I thought you got here before then. You missed a hell of a show. I can't promise a storm quite like that again, but you will see some big ones. Hopefully, this will be your first.

[RichmondTarHeel]

Just now, supernovasky said:

Got here late December 2016.

I moved up here in July of 2015, and the 30" i got in Jan 2016 was by far the most I've ever seen.

However, it's tainted me.  It's a little harder to get excited about 2-3, or even 4-6" snows.  It also made the past two winters excruciating, knowing 30"+ was possible in our area, yet we couldn't even get 2". 

I hope the Euro is right and you get to experience a 20" snowstorm this year!

[snowmagnet]

30 minutes ago, Bob Chill said:

@Maestrobjwa

One last thing, you hear us talking about bowling balls and ULLs and such. They are also king of big storms because of what is happening way upstairs. When a low closes off at 500mb there is a big, cold, unstable, pool of air spinning around at 18k+/- feet. When it closes off all the energy consolidates inside of the closed low. Not all closed upper level lows are created equal but they can be VERY fun. With high altitude unstable air combines with precipitation and lift (you'll see us use the term VV's at 700mb or vertical velocities) then things can be very dynamic. That's one of the ways thundersnow can happen. Plenty of lift and unstable air combine and get's wrung out inside of the closed low. Think of tall cumulus towers spinning around a closed low. That type of snowfall is VERY high ratio because it's really cold upstairs and the lift happens in the best dendritic growth zone (DGZ acronym). Bursts of heavy snow happen similar to convection in the summer. 

 

All this stuff make sense?

Thanks for all your explanations. I’ve been meaning to ask about the Closed low and WAA. This is such a great place to learn weather. 

[Cobalt]

GEFS big improvement on snow mean from 6z. Probably a lot of huge hits on 2nd wave. 

[aldie 22]

Ji just yelled fire in a crowded theater on FB and all of the Housewives of Loudoun county are in a tizzy

[Bob Chill]

12z gefs is sweet. VERY supportive of the second piece hitting us flush. Still plenty of spread and possible too much rain and such but a great run nonetheless. Better than 6z by a good margin. 

[H2O]

5 minutes ago, WxWatcher007 said:

Let's not talk like that.

I'm not even IN on this one but please let's not talk like that. 

You're in.  You keep posting in here.  Its ok.  We can keep it our little secret between ourselves.  No one reads these dumb storm threads anyways.  Everyone gave up and left.

[H2O]

1 minute ago, leesburg 04 said:

Ji just yelled fire in a crowded theater on FB and all of the Housewives of Loudoun county are in a tizzy

There goes the bread and milk

[nj2va]

1 minute ago, Bob Chill said:

12z gefs is sweet. VERY supportive of the second piece hitting us flush. Still plenty of spread and possible too much rain and such but a great run nonetheless. Better than 6z by a good margin. 

Big jump in mean QPF.  1.6”+ now.

[Maestrobjwa]

33 minutes ago, Bob Chill said:

@Maestrobjwa

One last thing, you hear us talking about bowling balls and ULLs and such. They are also king of big storms because of what is happening way upstairs. When a low closes off at 500mb there is a big, cold, unstable, pool of air spinning around at 18k+/- feet. When it closes off all the energy consolidates inside of the closed low. Not all closed upper level lows are created equal but they can be VERY fun. With high altitude unstable air combines with precipitation and lift (you'll see us use the term VV's at 700mb or vertical velocities) then things can be very dynamic. That's one of the ways thundersnow can happen. Plenty of lift and unstable air combine and get's wrung out inside of the closed low. Think of tall cumulus towers spinning around a closed low. That type of snowfall is VERY high ratio because it's really cold upstairs and the lift happens in the best dendritic growth zone (DGZ acronym). Bursts of heavy snow happen similar to convection in the summer. 

 

All this stuff make sense?

It's starting to...(dang man, you oughta write a small textbook on MA snowfall, professor Bob!) I'll probably have to read all that a few times (and I'm also still learning about how all this looks on the model runs. If I see that in conjunction with what you said it will make more sense, visually!). But many thanks for breaking it down--learning a lot!

[Cobalt]

Just now, nj2va said:

Big jump in mean QPF.  1.6”+ now.

Biggest QPF signal this far out in years. I'm guessing the most recent big one would be Jan 2016?

[showmethesnow]

1 minute ago, H2O said:

You're in.  You keep posting in here.  Its ok.  We can keep it our little secret between ourselves.  No one reads these dumb storm threads anyways.  Everyone gave up and left.

I heard @WxWatcher007is now in on this. It's the talk of the boards. So the question is. Can he reap himself?

[snowmagnet]

4 minutes ago, NovaTarHeel said:

I moved up here in July of 2015, and the 30" i got in Jan 2016 was by far the most I've ever seen.

However, it's tainted me.  It's a little harder to get excited about 2-3, or even 4-6" snows.  It also made the past two winters excruciating, knowing 30"+ was possible in our area, yet we couldn't even get 2". 

I hope the Euro is right and you get to experience a 20" snowstorm this year!

As you can see, most years aren’t as easy as January 2016. And some people complained about that year because it was the only thing we got. I’ve lived in the DC area for most of my life, and fortunately we have had most of the biggest storms during that time.  Winter here is generally better than N.C, but we have done lousy years where it just won’t snow. I loved Jan 2016 because I saw 30” at my house... most I had measure in 1 time. However, 2009-2010 has to be my favorite year.  2 feet of snow twice in 1 season!  Then the next year we had only 1 decent snow, but it brought the city to a halt.  Snow in this area is unique. 

[clskinsfan]

One way for you newer people trying to learn is to look at the upper level wind maps. They will show you not only the wind direction. But where the feed of the air is coming from. You can look at this 300K wind map at hour 102 and see the feed of the air into the area is from the S/W all the way from the Yucatan. Look at the LP position in WV. The low is spinning counter clockwise and pumping that warm air in over our heads. 

Now look at this map at hour 132. The feed of the wind into the area is from central Canada. The LP has moved east of us and the counter clockwise spin is now forcing cold air over the top of us.  There is obviously much more involved with temps. Like entrenched surface cold. Or rapid intensification of storms bringing cold down to the surface.   But these maps can help you understand why you see sleet or ice instead of snow when you are sitting in the mid 20's at the surface. And as Bob mentioned, you need to look at all levels of the atmosphere. You can be fine temp wise at 850 and the surface and think it should be snow. Then look at another level and see that WAA has occurred at that level. It really helps you understand how dynamic the atmosphere really is. Air currents are mixing constantly over our heads:

 

[Bob Chill]

15 minutes ago, Maestrobjwa said:

It's starting to...(dang man, you oughta write a small textbook on MA snowfall, professor Bob!) I'll probably have to read all that a few times (and I'm also still learning about how all this looks on the model runs. If I see that in conjunction with what you said it will make more sense, visually!). But many thanks for breaking it down--learning a lot!

The single most important piece of mental development with this stuff is to stop treating the surface panels on operational models outside of 3 days as reality or "sensible wx". That's not how it works. You have to understand what normally works here and what doesn't and how it looks in the upper levels (500mb). There are MANY times when the surface panels look great but in reality the setup sucks and vice versa. Don't ride the roller coaster and don't marry anything until inside of 72 hours. Models will almost NEVER get it right beyond 3-4 days with synoptic events. Accurately forecasting beyond 4 days is insanely difficult. Don't be disappointed or excited until 72 hours in and it will save you a lot of wasted emotional energy.

Personally, I'm sick of hearing things like "I can't believe how bad models jump around blah blah blah" when we're 4+ days out. Since we only track synoptic events it skews how good models are. During boring stable high pressure patterns models can absolutely NAIL a 7 day forecast. It happens ALL THE TIME. But when dealing with synoptic events there's a cascading process that is represented through mathematics/physics. One little error at the beginning has dramatic effects as you go out in time. Instead of being "surprised" by models jumping around with sensible wx with synoptic events at longer leads your should EXPECT them to. 

[showmethesnow]

After following this thread in regards to the GFS. I have come to the conclusion that those that only follow the surface and/or snowfall maps should probably think twice before they voice their opinion on a run. 500's on down are a thing a beauty as they are so close to hitting it big. As is looking at the CCB on the backside of our coastal I think that may be underdone as the heavier precip would probably make it farther west then currently shown.

[Skywalker03]

2 minutes ago, Bob Chill said:

The single most important piece of mental development with this stuff is to stop treating the surface panels on operational models outside of 3 days as reality or "sensible wx". That's not how it works. You have to understand what normally works here and what doesn't and how it looks in the upper levels (500mb). There are MANY times when the surface panels look great but in reality the setup sucks and vice versa. Don't ride the roller coaster and don't marry anything until inside of 72 hours. Models will almost NEVER get it right beyond 3-4 days. Accurately forecasting beyond 4 days is insanely difficult. Don't be disappointed or excited until 72 hours in and it will save you a lot of wasted emotional energy.

Personally, I'm sick of hearing things like "I can't believe how bad models jump around blah blah blah" when we're 4+ days out. Since we only track synoptic events it skews how good models are. During boring stable high pressure patterns models can absolutely NAIL a 7 day forecast. It happens ALL THE TIME. But when dealing with synoptic events there's a cascading process that is represented through mathematics/physics. One little error at the beginning has dramatic effects as you go out in time. Instead of being "surprised" by models jumping around with sensible wx with synoptic events at longer leads your should EXPECT them to. 

This.  Can we start every long-range thread with this quote?  Many thanks for all your analysis, Bob.  Back to lurking....

[Interstate]

shouldn't the Ukie be out by now?

[yoda]

2 minutes ago, Interstate said:

shouldn't the Ukie be out by now?

Meteocentre seems to have a lot of issues right now... so I am checking weathermodels

[showmethesnow]

2 minutes ago, WxWatcher007 said:

 

This is what I get for trying to be a serious poster in winter? Trolling?

F that. I'm here because this is where the action is.

I'm sharpening the scythe for all you fools who will be burned one last time by this awful winter. There will be no mercy.

Watch your back.  

I've got that covered.

[snowmagnet]

19 minutes ago, Bob Chill said:

The single most important piece of mental development with this stuff is to stop treating the surface panels on operational models outside of 3 days as reality or "sensible wx". That's not how it works. You have to understand what normally works here and what doesn't and how it looks in the upper levels (500mb). There are MANY times when the surface panels look great but in reality the setup sucks and vice versa. Don't ride the roller coaster and don't marry anything until inside of 72 hours. Models will almost NEVER get it right beyond 3-4 days. Accurately forecasting beyond 4 days is insanely difficult. Don't be disappointed or excited until 72 hours in and it will save you a lot of wasted emotional energy.

Personally, I'm sick of hearing things like "I can't believe how bad models jump around blah blah blah" when we're 4+ days out. Since we only track synoptic events it skews how good models are. During boring stable high pressure patterns models can absolutely NAIL a 7 day forecast. It happens ALL THE TIME. But when dealing with synoptic events there's a cascading process that is represented through mathematics/physics. One little error at the beginning has dramatic effects as you go out in time. Instead of being "surprised" by models jumping around with sensible wx with synoptic events at longer leads your should EXPECT them to. 

Last year’s March 13th storm was one of those that looked good until less than 24 hours from the storms. Then Lucy pulled the ball.  

[showmethesnow]

13 minutes ago, WxWatcher007 said:

My swing has become strong during this winter of suck, but even in my down time, I'm still training. 

You're double clutching on the back stroke. You should really work on that if you ever want to catch the big fish like me. 

[H2O]

5 minutes ago, WxWatcher007 said:

My swing has become strong during this winter of suck, but even in my down time, I'm still training. 

[Maestrobjwa]

25 minutes ago, Skywalker03 said:

This.  Can we start every long-range thread with this quote?  Many thanks for all your analysis, Bob.  Back to lurking....

Agreed...Oughta be a mandatory disclaimer...lol

[Maestrobjwa]

29 minutes ago, Bob Chill said:

The single most important piece of mental development with this stuff is to stop treating the surface panels on operational models outside of 3 days as reality or "sensible wx". That's not how it works. You have to understand what normally works here and what doesn't and how it looks in the upper levels (500mb). There are MANY times when the surface panels look great but in reality the setup sucks and vice versa. Don't ride the roller coaster and don't marry anything until inside of 72 hours. Models will almost NEVER get it right beyond 3-4 days with synoptic events. Accurately forecasting beyond 4 days is insanely difficult. Don't be disappointed or excited until 72 hours in and it will save you a lot of wasted emotional energy.

Personally, I'm sick of hearing things like "I can't believe how bad models jump around blah blah blah" when we're 4+ days out. Since we only track synoptic events it skews how good models are. During boring stable high pressure patterns models can absolutely NAIL a 7 day forecast. It happens ALL THE TIME. But when dealing with synoptic events there's a cascading process that is represented through mathematics/physics. One little error at the beginning has dramatic effects as you go out in time. Instead of being "surprised" by models jumping around with sensible wx with synoptic events at longer leads your should EXPECT them to. 

So when it's a synoptic event...beyond 72 hours, you look more at the overall setup than precip issues? Focusing more on what's happening at the H5 level (if I'm using the right term)? And how does this contrast with the last three storms we missed? (Were those more "boring", one-shot deal kind of things?)

[ers-wxman1]

27 minutes ago, Bob Chill said:

The single most important piece of mental development with this stuff is to stop treating the surface panels on operational models outside of 3 days as reality or "sensible wx". That's not how it works. You have to understand what normally works here and what doesn't and how it looks in the upper levels (500mb). There are MANY times when the surface panels look great but in reality the setup sucks and vice versa. Don't ride the roller coaster and don't marry anything until inside of 72 hours. Models will almost NEVER get it right beyond 3-4 days with synoptic events. Accurately forecasting beyond 4 days is insanely difficult. Don't be disappointed or excited until 72 hours in and it will save you a lot of wasted emotional energy.

Personally, I'm sick of hearing things like "I can't believe how bad models jump around blah blah blah" when we're 4+ days out. Since we only track synoptic events it skews how good models are. During boring stable high pressure patterns models can absolutely NAIL a 7 day forecast. It happens ALL THE TIME. But when dealing with synoptic events there's a cascading process that is represented through mathematics/physics. One little error at the beginning has dramatic effects as you go out in time. Instead of being "surprised" by models jumping around with sensible wx with synoptic events at longer leads your should EXPECT them to. 

This is a good post. Whenever I train someone on synoptic and mesoscale Weather I always go old school. Forecast Funnel approach. Start at 500 mb, find the features (s/w, trough, ridge, jet streaks) using an enhanced water vapor image then work your way down to 700 mb moisture plots, 850 temp advection, all the way to the surface. Plot a map by hand if needed. Know the pattern, study the climo, and paint a picture in your mind of what might happen from the top down. Then look at the models to understand why they are producing the end result, study some biases and base forecast on pure meteorology vs what four different models produce. The older Mets I worked with would come to shift with pro pencils, color charts etc. the ones that analyzed the meteorology were better off especially with severe weather. 

[psurulz]

Just wanted to thank Mr Chill for that great explanation of WAA and CCB.  He put it in English for us newbies.

[dallen7908]

In case anyone was afraid to ask, the H5 level corresponds to 500 mb.  At that level ~half of the atmosphere (by weight) is above you and half is below you.