MARCH 2nd-3rd 2018 Complex set up

Sorry folks I don't have time for in depth analysis of this one.  Personal duties call this week.  Ill do my best to add where and when I can.  Like myself and others have been preaching thus far this set up is too complex for a simple face value type forecast with modeling.  The full potential for this one will likely not be realized until less than 24hrs out and even then a nowcast for specific areas will likely occurr.  With such a dynamic set up, bust high and bust low potential exists.  Ill start the thread with a Bernie Rayno tweet:

NWS not buying it. They significantly cut down on qpf. And raised temps from yesterday’s forecast by about 3-4 degrees

syosnow94 wrote:NWS not buying it.  They significantly cut down on qpf. And raised temps from yesterday’s forecast by about 3-4 degrees

That's fine, we usually do better when they call for squat how many times have we seen THAT so far this season?? Hehe

Are they even mentioning any possibility of the snow and/or wind? If not, that is just completely irresposnsible in my humble opinion.

rb924119 wrote:

syosnow94 wrote:NWS not buying it.  They significantly cut down on qpf. And raised temps from yesterday’s forecast by about 3-4 degrees

That's fine, we usually do better when they call for squat how many times have we seen THAT so far this season?? Hehe

Are they even mentioning any possibility of the snow and/or wind? If not, that is just completely irresposnsible in my humble opinion.

Mount Holly mentions chance of snow for NWNJ, Upton always slow to the party... playing devil's advocate, they do have a very diverse geographic area to cover. We see tremendous differences in forecasts for their viewing area from LI to NNJ to HV. Liking where this is going though, another sleepless week!

rb924119 wrote:

syosnow94 wrote:NWS not buying it.  They significantly cut down on qpf. And raised temps from yesterday’s forecast by about 3-4 degrees

That's fine, we usually do better when they call for squat how many times have we seen THAT so far this season?? Hehe

Are they even mentioning any possibility of the snow and/or wind? If not, that is just completely irresposnsible in my humble opinion.

They’d are but just for areas N and W of the Tappan Zee. Even the point and click forecast for this highest coldest peaks in the Catskills it’s at best a rain/snow mix with temps over freezing. For my area on LI the temps are 50’s Thursday and the low 40’s on Friday

Syos - just trust RB in what he is saying. I have only interacted with him for a short period of time, but let me tell you, this kid has more knowledge and know how about Meteorology than this whole board combined. RB you are the best in my book!

No offense to the NWS and the TV mets but they seem to generally take the GFS literally as gospel up until about 24 hours before a system (probably moreso the TV mets; I think the NWS just tries to play it more cautious/conservative -- as arguably they should).
The NAM has been a reliable model all winter and it shows a changover to snow for most people on this board. Not sure why we'd ignore the NAM now, after some on here dubbed it "King NAM" all year. I don't dub it King NAM and I don't take it at face value. As I said at length in the Long Term thread last night, I'm leaning toward its solution because it seems more logical than the GFS output -- not because I just want to take one model and put my eggs in its basket. Nothing is certain yet, and probably won't be certain until the storm is actually here. But what it does show me is that there is a plausible (and in the NAM's calculus at least likely) scenario whereby the low deepens enough off the coast and brings in enough 850 cold air to turn this to snow for most. As for surface temps, remember we were comfortably above freezing two Saturdays ago and all it took was a few hours of heavy wet snow after to dark to dump 7 or 8 inches on some people. My forecast low for Thursday night is 37 using the warmer models. Wouldn't take much of a drop from that for me to have accumulating snow.

WeatherBob wrote:Syos - just trust RB in what he is saying.  I have only interacted with him for a short period of time, but let me tell you, this kid has more knowledge and know how about Meteorology than this whole board combined.  RB you are the best in my book!

Oh I absolutely do. No worries. I just like posting the NWS forecast for perspective. I trust him more than them.

billg315 wrote:No offense to the NWS and the TV mets but they seem to generally take the GFS literally as gospel up until about 24 hours before a system (probably moreso the TV mets; I think the NWS just tries to play it more cautious/conservative -- as arguably they should).
The NAM has been a reliable model all winter and it shows a changover to snow for most people on this board. Not sure why we'd ignore the NAM now, after some on here dubbed it "King NAM" all year.  I don't dub it King NAM and I don't take it at face value.  As I said at length in the Long Term thread last night, I'm leaning toward its solution because it seems more logical than the GFS output -- not because I just want to take one model and put my eggs in its basket. Nothing is certain yet, and probably won't be certain until the storm is actually here. But what it does show me is that there is a plausible (and in the NAM's calculus at least likely) scenario whereby the low deepens enough off the coast and brings in enough 850 cold air to turn this to snow for most.  As for surface temps, remember we were comfortably above freezing two Saturdays ago and all it took was a few hours of heavy wet snow after to dark to dump 7 or 8 inches on some people. My forecast low for Thursday night is 37 using the warmer models. Wouldn't take much of a drop from that for me to have accumulating snow.

Rather than give this a thumbs up and enhance your already burgeoning reputation, I am re-posting to say I agree 100% with this post.

Let me tell you, if that upper low actually is in the position Bernie indicates above and is intensifying, wild things can happen as I was saying a few days ago. You can throw out all the temp forecasts and precip type from the models. That upper system coupled with a bombing low off the Jersey or Delaware coast can bring a “holy sh*t” moment when you look out your window

Bob quick question not complaining but just honestly have no clue. When you say holy_ moment is that just for the northern members and NYC or does that include the jersey coast too. I have friends traveling and don't know whether or will be an issue or not here. I would just like to help them out.

Track that could potentially be down to the coast. But the important thing to remember is this is going to be such a complex setup that specific effects in any one specific location may very well not be know until about 12 hours out, if not a complete "nowcasting" situation where you don't know until it is happening.

Ok thanks bling. I am fine with whatever happens. I was just hoping to let them know. But thanks for the info. I will just tell them to pay attention,

Well the 12z NAM is no winner for snow lovers. lol. A brief changeover to snow far N and W but still rain for everyone for the most part. This is not consistent with what it showed on the 0z or 6z, so I'd take it with a grain of salt until we see how it goes later today. Again, with this system we will not be able to live or die by one model run (if that's ever a good idea anyway). I'm skeptical of this run anyway because unlike previous runs where the low slowly drifts northeast (almost stalls) near LI, this run has the low drift . . . south/southeast (??) away from the coast. Not sure what that's about. lol

billg315 wrote:Well the 12z NAM is no winner for snow lovers. lol. A brief changeover to snow far N and W but still rain for everyone for the most part.  This is not consistent with what it showed on the 0z or 6z, so I'd take it with a grain of salt until we see how it goes later today.  Again, with this system we will not be able to live or die by one model run (if that's ever a good idea anyway). I'm skeptical of this run anyway because unlike previous runs where the low slowly drifts northeast (almost stalls) near LI, this run has the low drift . . . south/southeast (??) away from the coast. Not sure what that's about. lol

Thermal profile was colder than either of its 06z or 00z predecessors, so I'm not worried about what its p-type spit out right now. Biggest difference to me was overall evolution at H5 because instead of phasing in all of the northern energy at once, it did incrementally. This is important because it didn't allow such explosive development to occur as rapidly. Also why it didn't stop the forward movement of the lower-level circulation like it did in previous runs.

Another very important takeaway is that it shifted the entire H5 progression about 50-75 miles further SOUTH. That's HUGE.The further south the entire system is, the less help we would need from dynamics.

Not really sure why it split the energy this run (northern stream), though. I don't know why it develops that shortwave ridge between the two pieces after the initial connection/phasing occurs. Once that happens, the streamflow should unify, not fracture like it did there. Its 06z run makes more sense at H5 to me in this regard. Granted, the 06z also had a more amplified/sharper ridge which allowed the northern stream to dig further and interact more wholesomely, but even with that, the 12z depiction of the actual vorticity is generally in the same spot as 06z at the time of first interaction. Why it breaks it in half and allows the second half to consolidate northward instead of sliding right into the larger anomaly is suspicious to me.

RGEM looks A LOT like the UKMET from last night

CMC looks really pretty good at H5. Worlds apart from the GooFuS and resembles 06z NAM.

Sadly I don't have access to the CMC at this time, but if it resembles the 6z NAM I'll take it for now. lol The NAM, even in its relatively unappetizing 12z run, has been consistent at bringing cold air into the system. Dynamically speaking that makes sense. Lets see how things continue to play out.

Interesting the GFS has no trouble pulling in cold air at the 850 level to our south and west. But with the surface low developing over New England it keeps a warm layer aloft right over our region. The H5 low is still back over PA until Friday midday.

RB - you still not buying into anything the GFS is saying?

HO-LY UKMET.......