psuhoffman

Buffalo changes over

Naw busy packing and this isn’t looking promising. Nothings changed synoptically but the models are seeing that screaming SE flow and obliterating any cold pretty fast.

My 2” call for Binghamton might have been too high. I don’t think they get any snow on the 0z NAM. It pretty much starts as sleet and freezing rain even up there.

I'll see if I can find them on my way to snowshoe

no zoom tonight, I have too much to do to get ready for the weekend. Hopefully by next week we will have something more promising to track.

We should drive 5 hours so we can get 2” of snow and ice changing to rain?

Except its not just the NAM. Check out the RGEM. Changes to sleet and freezing rain all the way to Erie!

I know the storm you're talking about and it was a different setup. Models missed a higher mid level warm layer around 700 mb. I am only bringing this up because I am very familiar with central PA climo from my years at PSU. For them a perfect setup is a cut off amplified H5 moving through around DC with a surface low tracking up inland but east of the blue ridge. In winter with a cold airmass in place that should be a setup for a big snowstorm in places like Deep Creek, Altoona, State college, not a change to ice and dry slot! It doesn't matter for us...just saying its kinda ridiculous to have a H5 and surface track near DC and a flip to non snow all the way to extreme northwestern PA. Put that in perspective...thats the equivalent of a H5 tracking across southern NC and Cape Hatteras and a surface low tracking off the NC coast and 100 miles east of Ocean City and us flipping over!

It did...but that storm the low tracked up into the delmarva and the warm layer blasted some sleet and a dry slot into south central PA to places like Harrisburg. That was significantly further NW than thinking...but I've seen that before, especially with a bad upper level track in that case. But here the upper and mid level track is through VA just south of DC. The surface track is up just west of the bay. And the NAM is mixing with sleet and freezing rain all the way to Lake Erie. That seems a bit off. Ive never seen THAT!

I have no doubts the warm layer will blast through this area with no trouble...but I have to think the NAM is way overdone overall. It's really indicating not much snow anywhere...flipping everyone to ice even to the NW edges of the storm. I have never seen that before when a cold airmass in place in January and a surface track east of the blue ridge. To change over all the way into western PA?

It didnt make much difference for us yet, but this was the first run of the NAM where it went the other way and had a less aggressive push of the warm layer. Also a slightly better h5 and surface initially. Baby step...we would need a couple more adjustments like this to see much benefit though.

NAM coming in less amplified, slightly south, with less riding and lower heights over the top through 42. Let's see if it matters at all.

The euro is trying for another NS phase job with a gulf system next weekend. Might not pull it off this run but interesting and somewhat similar to this. We were discussing this in the last few zoom chats... JB is right about one thing...this is the kind of pattern where you can get the NS to dig far enough south to get these amplified systems coming up out of the gulf coast. But they aren't going to be 1993...even for a triple phased system that was a once in a lifetime thing. We've had several other triple phased storms but they usually phase and bomb further north like the November 51 and January 66 storms. So he isn't wrong that this is the kind of pattern to get the NS to dig down and phase and get amplified storms but he goes full over the top hype mode as usual. Also its not necessarily what we want as were seeing now these types of storms can cut if we dont have enough confluence to our north. The key is to either have something blocking the flow, a well timed 50/50 or wave coming over the top in front of it... and it would also help not to have another NS wave diving in and phasing right behind it!

The euro had another decent upper level low track and improved the surface a bit. SLP tracks from ORF right up the bay then into eastern PA. If we were to continue to get these minor adjustments and the upper low were to track another 30-50 miles southeast and the surface low were to track up just east of the bay, it would cut down on the low level warmth quite a bit...might increase the WAA thump some although I think the angle the WAA precipitation is coming in at has more to do with that then anything else at this point...but it would increase our chances of some snowfall Monday morning with the upper low pass also. On the WAA snowfall...We want the trajectory to be more south to north and less east to west with the angle of that WAA precipitation. The more negative tilt that banding is the longer it will take to progress northeast and we will lose the column faster. A further east track of the mid level and surface features could help with that some also. There was a minor improvement in that regard this run over the previous one.

At long range the key is to identify the opportunities for amplification near the east coast according to the longwave pattern. The guidance will struggle with the details like phasing, which SW to amplify, track. I don't bother with the surface maps at all past 5 days.

Been busy but I see no changes...still see threats focused on the 20-22 and 24-26th periods.

My guess is they all underperform on the front and overperform on the back of the storm. In the end they probably all get at least 6" and some of the more favored upslope locations like Snowshoe and Timberline probably closer to 10-12 with the upslope being the majority of that.

I will be there also...I only expect several inches of snow/ice from the front side of this storm...but they will clean up on the backside once the winds flip to the NW. That's perfect upslope flow and it's the kind of snow they get very high ratios, 20-1. I could see them getting 8" from that late Sunday night through Monday morning.

The h5 pass is further NW on the NAM, not necessarily shocking at range...if the euro/gfs h5 pass is more accurate I think a period of snow early Monday is definitely a possibility. Especially if that feature continues to trend a little SE as it did the last couple runs on the globals.

Models are starting to pick up on the mid level warming so it’s offset this trend in terms of snowfall results but we’re finally actually getting the trend we want since 18z wrt the NS SW diving in behind and it’s corresponding interaction with our storm. 18z euro to 6z euro It was an incremental trend the last 2 runs. Results in a slightly weaker and further south h5 track initially. It’s not enough YET to change our fate, and it’s been offset by models starting to realize the warm layer issues…but if that trend were to continue it could lead to the chance for some snow with the h5 pass. It could also help with the WAA some if we continued to see this trend but we would need several more bumps and the improvement would likely only be incremental since that part is mostly baked in at this point because of how amplified and cut off the h5 is to our south and the lack of confluence over the top to resist the SE flow ahead of it.

Synoptically it’s the same. It’s simply “seeing” the mid level warm layer now as we get closer. We knew this was a risk with that screaming SE flow. Been talking about it for days. The Gfs just suddenly sees it.

0 chance i get 10

I will just use this one thread from now on with updates for zoom chats. I will open the chat tonight at 10 and stay on until the GFS is out. I don't mind leading the chats but as others have said it would be great if anyone else wanted to contribute!