February 12th-13th 2024 Pre-Valentines Day Storm Potential

I also should add as a third caveat as the storm takes on a classic wrap around, rotating bands look, some dry slotting could develop somewhere.

If this works out thank the n/s. It's truly the reason why this has a chance. It's been digging more south run2run.

Last night's Euro h3 jet.

Well, one map has me 6 inches and the other 12,LOL.I am now in nowcast mode, and will know tomorrow am looking at the radar and seeing the rate of snowfall where my area stands .

Couple questions I have. How much more is the n/s going to dig and how fast is this going to bomb. Both are critical to sensible weather. Based on the PNA/EPO a busy n/s makes sense.

A very humbling storm for pro mets.

Ill take 06z gfs plz. Just saw news gave blanket 8 to 12 for entire area. Was on phone not sure what channel it was. They mention st i didnt think sbout. 40mph winds and heavy wet snow on trees...power outages possible. Sometimes that can be worse than a high wind event.

Wow. We’re 18ish hours out from the onset of precip. I like that on some models - most notably the euro - there’s even wiggle room to absorb some northern correction ticks and still see significant snow for most. The HRRR really for me only starts to get into the range we need from noon and on today. For me this all comes down to a point that Homenuk (earthlight) made and Mugs referenced which is the convection to the south. How many times have we seen or even relied on convection down south to be STRONGER than modeled to help pump heights and latent heat release to force storms more north into our area? Other times we have looked great (Dec 2020 or March 2017) and those trends pushed the best axis of snow north. Yesterdays positive trends were directly correlated to OPPOSITE trends. The severe weather busted low and in this case that helps. There is a whole day left of more convection today and that is the wildcard. Does it bust low? Does it overperform unlike yesterday and move things north like we have seen in the past? Or have we built in enough insurance with yesterday south trends to absorb SOME northern ticks without sacrificing significant snow? I’m hoping for option 3!

I'm currently under an Advisory here in Old Bridge with 5-8 inches predicted. Should be interesting...

heehaw453 wrote:If this works out thank the n/s. It's truly the reason why this has a chance. It's been digging more south run2run.

Last night's Euro h3 jet.

Yes but why is the n/s digging more and more.  It all starts with the big picture stuff we have been discussing out over the Pac.  SOI crash/MJO are the big ones IMO.  This reshuffled the pattern.  It made its way to our neck of the woods.  It lead to the energy in the N Pac that I had been calling he 50/50ish low to buckle the jet to our NE; combined with the -EPO ridge going up to our NW, effectively pinning a deep cold air source into S Canada.  The stout -EPO in turn dug energy on its eastern flank which lead to our "mogul" to pop, which was the remnant of our nice +PNA ridge from a few days ago that started the cold air mass into Canada and our n/s digging.  This little mogul feature was critical in helping press the n/s energy around the back side of the lobe of the TPV sitting just SE of the Hudson Bay.  Its everything together that has this working.  While that n/s energy is def a key piece, it doesn't do its dirty work without everything else well oiled and tuned up the way it is.  

For all the folks who gave up on this, THIS is why we point out the pieces to the puzzle and discuss how things need to come together in order for this soln or that soln can work.  THIS is why most of us do what we do.  In recent past when we have talked about the players things haven't worked out, but every now and then things do come together just right.  Now that said obv nothing has happened yet so take this for what its worth.

I will also make a separate thread for Snow maps only for people to post a map if they wish to make one.

Gonna need the deamping/southern shift trend on the Euro to stop now! Thanks! I think it’ll come back, but it’s a new wrinkle for now.

the 06Z euro was a bit less intense than 00Z mostly due to a slightly later development of the storm. If the ULL closes before hitting the coast it's going to make a big difference in how far north the axis of heavy snow gets northward. Right now that's my big wild card is how fast that can close off. By the nature of the n/s I'd sooner than later. There's just to steep a ridge in the PNA to think otherwise IMO.

MattyICE wrote:Gonna need the deamping/southern shift trend on the Euro to stop now! Thanks! I think it’ll come back, but it’s a new wrinkle for now.

The ULL has got to close off before hitting the coast. That's why the 06Z Euro was a bit less than 00Z. I'm leaning to early close off due to the ridging in the PNA that slides the n/s energy quickly to meet the s/s.

Frank_Wx wrote:There’s a - what *COULD BE* - a nod back to the north track happening. Although the 6z NAM was south, the latest HRRR and 6z Icon bumped the low back to the north. This puts NYC out of major snowfall, while everyone south of there sees little to no accumulation.  

12z HRR went back south. Looks like last night's output

So less concerned about a northern track but more concerned about this becoming a “southern slider”

6z euro ensembles…

Yeah. Look at the ULL closed off and mature and the cyclonic curve on 12Z HRRR.  That's going to have banding in it with very intense rates as shown. That precip will get thrown back inland quite a ways due to the tilt. Also any storm that closes off and you think you have a handle on it. Nope. Stalling is always an option for something that is cut off.

sroc4 wrote:I will also make a separate thread for Snow maps only for people to post a map if they wish to make one.  

Great map Doc!
Curious ,though, about the latest big southern shifts in the models.My area in the LHV you have 12 to 18 would be getting 6 to 8 or less with that shift.You don't seem to be buying that in your map.

docstox12 wrote:

sroc4 wrote:I will also make a separate thread for Snow maps only for people to post a map if they wish to make one.  

Great map Doc!
Curious ,though, about the latest big southern shifts in the models.My area in the LHV you have 12 to 18 would be getting 6 to 8 or less with that shift.You don't seem to be buying that in your map.

Yeah, if the shift continues south, there might need to be a revisit on the 1st call.

Irish wrote:

docstox12 wrote:

sroc4 wrote:I will also make a separate thread for Snow maps only for people to post a map if they wish to make one.  

Great map Doc!
Curious ,though, about the latest big southern shifts in the models.My area in the LHV you have 12 to 18 would be getting 6 to 8 or less with that shift.You don't seem to be buying that in your map.

Yeah, if the shift continues south, there might need to be a revisit on the 1st call.

Right, the 6OZ Euro now has me at 2 to 4,LOL.These wonderful Miller B's....I hate and detest them! A narrow band of heavy snow with sharp cut offs.Give me a multistate 20 inch plus Miller A please!

A madonne-like 12z NAM run incoming...

The surface low - for the most part - is following the same path as 6z run but the ULL seems to be slightly more south. Much more expansive precip field as well, which compensates areas to the north.

Frank_Wx wrote:So less concerned about a northern track but more concerned about this becoming a “southern slider”

6z euro ensembles…

Which would be ironic since that's what the GFS had last week. Doesn't seem likely to me though. I think the northern extent of the snow is being limited by the more south positioning of the storm, but I don't think it goes completely south on us. I don't think . . . .

Looks like the 12z NAM actually came a bit back north from the previous run. Still a lot of waffling and uncertainty with these models. Nothing written in stone yet for sure.

Frank_Wx wrote:So less concerned about a northern track but more concerned about this becoming a “southern slider”

6z euro ensembles…

My mental health would slide right out with it. But I appreciate the warning that that's not out of the realm of possibilities. Staying grounded is hard on a morning like this.

12z NAM (current)


6z NAM (previous)

billg315 wrote:12z NAM (current)


6z NAM (previous)

Definitely slid north from those maps. Took me from a foot to 7-8.  Should be in the goods either way. I hope for a solution that works best for all and not one shafting a good chunk.