MillvilleWx

I know this doesn't pertain to us, but to answer your questions, this run would put them at #2 all time. That would be insane. I'm going to check out what they have been up to for messaging purposes. Just got settled in at work.

The globals still have that issue at times. This could very well be one of those cases. The depth of cold air initially is pretty good. There will be a fight between that and traditional evap cooling with rates. We know how things roll in these parts. The good news is the storm will come in hot and heavy at the very least. Probably some rippage before any flirting with thermals.

Yup! That’s something I’ve been noticing and trying to get people to understand. This is one of those situations where things can come in hot and heavy really dump for several hrs before any type of worry of mixing concerns. We go through this down here all the time. If you’re north of I-70, likely all snow. Between I-66 and I-70, could very well stay all snow, but perhaps a short period of pinging. Urban areas inside beltway highest chance of mixing within that second zone. Southern MD and south of I-66 probably see some type of mix given the potential 85H jet being progged. Going to be a fun storm to follow through the end.

They aren’t uncertain on the overall scheme that will unfold but small shifts in certain features can lead to detrimental shifts in QPF/Snow/Ptypes. NWP is not exact and will never be exact. It’s a complex physical process that so far we have done a crazy good job at depicting with better leads as we move through time. This storm has been on the radar for over a week….this was a very rare occurrence even 5-10 years ago, but here we are. The key is being able to parse details and understand the overall footprint of what is going on to depict these outcomes. Probabilities and utilizing ensembles who have different parameterization baked in to offer different results pending other variables are importantly in forecast things with greater certainty while also showing a probabilitistic outcome which is important for stakeholders. Considering the circumstance, NWP has been pretty good with this event and wavering at leads is par for the course. It’s up to humans to know how to interpret the data. There is no magically perfect solution to everything and until we solve every intricate detail that pertains to meteorological phenomena, we will never ever ever get it 100% on the nose. This isn’t finance when you count money and the answers are finite properties that can be discerned through analyzing accounts and what not. This is a complex, physically driven paradigm that takes more than just regurgitation when it comes to providing a forecast. If you’re looking for something more concrete in analysis, you are in the wrong hobby/profession.

No one storm is alike, but I do believe we’ll see QPF step back some in the areal extent, however the AI isn’t going to account for more complex mesoscale dynamics such as FGEN which will play a significant role in this setup. I’m hoping people realize that at the current juncture, we’re going to see some pretty sick banding during the storms height with some periods seeing better ratios than others during the event. That’s why I feel there will be dual maxima in these parts and those details will not be solidified until much closer to game time, and even so is very nowcast in nature. Trends are good so far for much of the region. It’s looking like a high end advisory at the worst and WSW potential increasing. Good times!

Seems like another example incoming. I would be pretty excited if I was along and north of I-66 for this one. Going to be a long weekend leading in. Start my last stretch of night shifts this evening, the final of the back-to-back-to-back. Let’s reel this sucker in!

You and I know that likely won’t happen, but I like where we are for this event. There’s growing consensus on some really solid 85H FGEN across our hood. Plus we are further east than the fall line so MIGHT get a little help on the transfer fun as noted by some of the globals. I’m not expecting a jackpot by any means, but it’s a good situation for us!

There will be some decent wet bulbing once the moisture feed enters the air and starts moistening things up from the top-down. It’s one of the reasons a lot of us will start snow and stay pretty much all snow. The dividing line will likely be in VA and MAYBE portions of St Mary’s County in MD. Rest should be snow. Have to see how it trends as we move closer.

Anyone along and just north of the M/D and across places along and west of Rt15 should be keeping close tabs on this one. Looks like a nice event starting to spruce up on guidance. Plenty cold and just need the moisture push. I’m think a warning level event is creeping up in probability. Not going to sound the alarms yet, but probably a good chance one of the better banding setups will be over northern MD into southern PA. I’ll check in over the next several days leading in! Hope everyone here is doing well and had a great set of holidays. Let’s reel this in for the Mid Atlantic.

There will be some incredible staying power for the snow and ice that falls with this one. The Arctic will be paying a visit regardless of final outcome. I hope people are ready for this one.

One of the things I’ve been alluding to on these runs and outputs are dual maxima showing up in the precip/snowfall panels. You’re starting to see that come to fruition in the more hi-res guidance and even to a degree in the Ukmet with a northern max and “southern” max within the sub. The 7H maxima aligns over the north with solid convergence pattern towards the M/D (I-70 to MD line) and the 85H FGEN situated between I-70 to I-66. If this kind of synoptic scale evolution holds, this would lead to pretty good banding structures with rates capable of 1-1.5”/hr in the strongest zones of lift. That is a beefy 850-700mb moisture advection regime being advertised with the disturbance out west taking on a more neutral to slightly negative tilt at 5H. This was a good set of runs for snow lovers north of Fredericksburg. Feel for those in Southwestern VA and Southern VA. This is a nasty CAD wedge progged. Ice storm hell signature for I-81 corridor south of I-66.

I was parsing through DESI earlier and looking at the 1D plots and noticed a small SBCAPE signature over my hood so I took a spatial look. There will be some sneaky good snow shower/squall activity with this one. I wouldn’t be surprised if areas north of I-70 grabbed a quick 0.5-1” with this type of setup. I think further south will be tougher for good accums, but flakes will likely fly anyways to give that winter feel in the air. Hopefully people enjoyed the milder temps recently. The bottom drops out soon and it won’t be coming back anytime the next 10-14 days, maybe longer.

Appreciate it, Randy!! There’s another poster in here from WPC as well, although for whatever reason I can’t remember his tag. He’s a red tagger that will pop in from time to time. He’s been super busy recently. I’ll have to ask him to check in over the weekend as we get close. Let’s reel this -ish in, shall we

No question about that. So happy I went there for my degree. Met and made friends with some amazing people along the way. Hopefully all is well up in LNS territory! Let’s kick this January off with a bang!

He deserves the reddest of tags. Pete is an amazing meteorolgist and one of the primary Winter Desk forecasters at WPC. I went to school with Pete. Great guys and very knowledgeable. This is the type of work that is done when looking at the big picture. It’s not just hemming and hawing over every single deterministic output. Yes, it’s great to look at, but parsing the details on the why is why we love what we do. I’ve been utilizing Cluster Analysis via DESI v3.2 which I unfortunately can’t share and trying to see the behavior of ensembles and potential outcomes. Pete broke down the primary features and some sneaky elements that could very easily sway the forecast. I hope people get a lot out of the information provided. It’s one of the ways I learned about how things work in the synoptic world when it comes to Winter Systems. Years of just reading on here from previous Red taggers and knowledgeable posters. Been a great experience with a ton of laughs in the mix. Hopefully we can bring this one home!

All the hemming and hawing over the GFS deterministic output all while the GEFS has improved, for most run to run for the past 8 cycles lol I'm not saying we're going to get clobbered or that we're going to miss. I'm saying the trends are still decent for the area despite the deterministic outputs. I'm not worried at the moment. I'll let you know if I am! If there was anyone that should keep close tabs on the setup for shifts, it's NE MD just due to the nature of the confluence. Still could get snow up there, but it's likely to be greater further west and south. I have family near where I grew up, so I'm watching that area closely.

Yeah, and considering the time frame of expected impact and spread, I'm sure my colleague went pretty conservative on QPF which is one of the reasons the output is lighter than what most of the recent deterministic have shown. I will say the current output on the snow is a good sign and is within that general grand ensemble mean from the cluster analysis depicted on the 12z suite. I think 3-6" with as much as 8" or 9" is plausible in the setup as shown. Still time for adjustments in either direction but remain cautiously optimistic.

I just came here to mention this as well.

This is my feeling as well and the fact it agrees with the majority of ensemble outputs on all major globals when assessing cluster analysis gives me optimism

Inside 60 hrs. Still a ways to go!

The model very likely has a small decision tree approach when it comes to ptype dissemination, so any nose above the 0°C threshold will ultimately shift the ptype to a more mixed variety. Pending the depth of the omega between 850-600mb and the intensity of the precip, the result could still yield snowfall, albeit more clumped aggregates and lower ratios. The warm advection regime within the boundary layer will ultimately cause a changeover somewhere with the current southerly flow magnitude being progged. Climo suggests those Fredericksburg on south would have the highest potential with Southern MD likely to be next on any northerly adjustment. I think those that are along and north of Rt50 should stay all snow with this one with realistically the zone north of Fairfax/Northern Prince William/Charles counties probably maintaining most, if not all snow. Would need this storm to cut further north to threaten those zones. Best accums will be within the 7H and 85H FGEN areas with the northern periphery seeing best ratios to offset the “lighter” precip potential. 85H FGEN will have slightly lower ratios, but more precip. This is a good dual maxima setup wherever this sets up. Jury still out, but I still think this ends up a Central VA on northward storm. Ensembles have been pretty insistent on that. GFS waffling on location should be a major red flag in terms of forecasting. Until other models follow suit and/or GFS becomes steadily locked in for multiple days, I don’t see its 12z representation being the final solution.

Oh God

New longevity record?

Yoda, I have two things. First, the black and white maps do look decent to my trained eye. Have to take a closer look once the other visuals are out. Second, I’m gonna start billing you for my eye doctor after all these years trying to read these damn things

I actually will purposefully add more value to that area and other types across the CONUS the last 30 min of my forecast time frame before the deadline. It adds a lot of value to the forecast. I’ll be keeping tabs on that spot for sure with this setup!