jwilson

The FV3 has given us about 10 feet of snow over the course of this winter. It owes us big time. Add in this beast and it means the FV3 will be paying on the principal until it dies. (Sort of like me and my student loans)

Sadly, yes. This was the biggest snow we've had all winter and it came and went in about four hours. Precip ending much sooner than expected, honestly. At least it appears we won't get much plain rain to wash things away.

All sleet now in Bethel Park/Mt. Lebanon. I was out for about an hour or so and couldn't even keep my car clean, so I gave up. Even an hour ago with some intense rates, it was not a pure snow. Lots of ice pellets/graupel mixing in. I have some pictures I'll post later. We're approaching 4" but I think accumulation is over in terms of snow.

I think a lot of the clown maps are deceiving due to their failure to differentiate snow and sleet. Heavy wet snow would probably fall as a 7:1 to 12:1 ratio, while sleet is in the 2:1 or 3:1 range. As an example, averaging out 10:1 snow ratio and 2:1 sleet ratio, the NAM gives Allegheny county between 1 and 1.25 inches of total precip. Ferrier correction calls for 2.5" of snow, or so, which would be about 25% of the total precip. Under that calculation, I'd estimate there's about an inch of just sleet, then some plain rain plus ZR towards the end. That half inch of precip that falls as sleet shows up as another ~3-6" of snow on some models. Looks like the 850s warm somewhere between three and six hours after onsent of precip. Given our history and the way things have gone this winter, I'm inclined to sway towards a conservative snowfall estimate and thus a warmer overall solution. The high being off to the East instead of our North gives me even more pause. Using another example: the HRRR simulated radar still shows snow at 15Z, but the surface temps have already warmed above freezing. That's four or five hours of snow, maybe even less. This system could manage heavy rates (say >1" per hour), for sure, but I believe a system with that sort of convection is also more likely to flood in warm air at a quicker rate (someone correct me if I'm wrong on the science). This is a long-winded way of me saying I'm still not buying into a significant snowfall along the warm "plain." Places in the mountains and further north will probably see upwards of 10"; a shame we can't get in on that game. It will be interesting, though, seeing how this storm verifies relative to the GFS vs. the Euro.

I'm not finding much reason to be impressed. Given history, I'm sure 1-3" is a safe bet. The 850s are screaming from the south, so the flip is always imminent with the position of the retreating high. We aren't in a strong CAD location. Might it be our last snow until March?

Agreed with you and then Mike (about the screaming southern jet). I don't really trust the guidance beyond Day 4 this year, so I guess it would be unfair of me to say with certainty what will happen. All we have is how the preceding days of winter have gone. The tropical forcing might be changing a tad, though we're still dealing with Phase 7 MJO effects, so that's where the hesitance comes in. If we can get the MJO to actually move towards Phase 1 at a decent amplitude and stop meandering, there's our chance. The western trough will hurt us in the meantime. Hopefully, as you've shown, it does flatten and limit that SE ridge influence in the coming days. I don't know enough to say which is cause vs. effect, as we've also been dealing with a pretty strong high over the Azores most of the winter. Maybe we luck into something eventually.

The only thing that might save this storm is the timing of it with a transient -NAO. If we can close a block in at the right time, we may be able to keep the confluence locked in rather than escaping and the low tracks underneath us. Right now, though, I agree that this storm is heavily favored to cut like the rest of them. The Euro keeps the low in Tennessee, which is about as far north as we can let it go. There is another wave behind it (Friday/Saturday) which could be a better shot, or perhaps more likely suppressed. I give us about a 2% chance to get the timing right.

Thank you! I thought that storm back in November was our biggest of the season, but I guess it wasn't as big as I thought (most area measurements for it I see are <2").

We technically had an advisory for the storm that missed to the north back in January. Of course the advisory was cancelled, so you probably can't count that because it didn't verify. Officially, I'm finding the biggest snowfall at the NWS location is 3.4" on January 20th. Locally, we've had a number of 2" storms this year, but 3" is probably the absolute max. Annoying I can't measure at my place so I don't have specifics.

We just had the wettest year on record and we're already starting out this year wetter than last. Despite that, we're below normal on snowfall. I guess the question becomes whether the pattern changes before next winter, and if it does, do we end up in a dry pattern. Seems like a waste of all this moisture to not get a decent snowfall out of it.

48 hours later and I'm a lot less optimistic about the next week. The -PNA is killing us, and the MJO appears to be dying in Phase 8 as it did last time. It honestly wouldn't surprise me if it looped around the COD and re-emerged into the warm phases again. Maybe that's unlikely to happen given other conditions, but this winter has been a real test of patience. We're back to tracking cutter solutions in the mid-range. Maybe March has a freak out of sorts, which is still possible, though unlikely. The only way I could see us salvaging something is with a -NAO block. The problem is we haven't been able to establish one, or anything close to it this year. The big +AO is just another negative factor. Not quite ready to cancel the rest of winter, but I'm pretty darn close. "I want to get off Mr. Bones' Wild Ride."

Good news is we have a lot of threats to track for the time being and what looks to be improving pacific / tropical trends. Models are locking onto multiple events of southern rather than western origination. Near-team: we have what looks to be one or two more cutters to deal with before changes. Friday is the certain one before a southern slider drives by on Saturday. GFS tries to connect some of this energy to the stuff crashing into the pacific NW as it crosses the country. The Sunday system is the other possible cutter, but is more intriguing for us locally. The evolution is unusual, and I would think the position of the low would mean rain or mixing for those of us susceptible to that WAA. At least until the low gets east of us. GFS seems to hint at redevelopment off the coast, but it's a quick mover. Long-term: the main event I am looking at is focused on next Wednesday. The GFS has had a pretty strong signal for something significant for five runs in a row now. There have been minor changes over those runs, but it a classic Miller A look, and despite the time from onset, the model's consistency is what has me intrigued. I won't get too mired in the details yet. It has slowly shifted north the last three runs, even getting us into mixing territory as it dropped the confluence. The antecedent storm seems to pump heights ahead of this one, which helps it dig and explode. Keep an eye out. In fantasy land, there are a couple more southern solutions after that primary one, but that's too far out to focus on other than - at least it isn't showing cutters. I think what's driving these changes for the GFS is the expectation of a strong-amplitude MJO Phase 8. Obviously, that expectation is a difficult one to rely on, and if the evolution is any different, we may not maintain the current favorable looks. The remaining teleconnections show possible improvement, as well, including a crashing AO and a possible blocking element from the NAO regions. Still not an ideal western ridge, though.

Accumulating pretty quick. Was out during the first hour of snowfall and even the roads were getting covered. Didn't see much in the way of salt trucks for preparation. Based on early returns, probably 1/2" or so already, this looks like it might overperform. Sadly it all gets washed away tomorrow through Wednesday, just in time for another cutter and rainstorm. The GFS is showing backend snows, probably overdoing lake effect or something, but maybe we get something there. Next week might have potential, but at this point I'm not wasting my breath on it, because a couple models hold the energy until the high passes then cut the system. Until the pattern actually changes, I'm not getting excited.

This just about sums it up for us. Welcome to the Screw Zone™ for all time.

As expected. I don't know about you guys, but I am totally fatigued watching these cutters over and over. And for whatever reason the GFS models these things almost perfectly. Anything else and it just shrugs its shoulders. I'd be curious to know if places in the midwest are setting snowfall records this year.

Don't look now, but the 6Z GFS gives us a pasty white bomb for next Friday into Saturday. Closed low over the Delmarva and slowly treads off the coast of New Jersey. Starts right where we want it really, just south of Pensacola in the GOM. A true Miller A feast. Setting up PD3? That is one of the best weekends. Now how long until it completely dismantles that solution? I give it until 12Z, haha. The first event coming through (Monday) is looking weaker on the GFS. Maybe a 1-2" flop storm. All the energy is held back in the West until it consolidates and bowls through as a cutter. Pretty much what we expected, but it could help setup that following system. I'm sure the current look will flip-flop but at least it's something to watch.

Funny enough, the 18Z FV3 keeps a similar look, though it is less wound up early and shifts the heaviest snow south into the mountains and Virginia. The Canadian looks like the GFS, which shows the familiar cutter look. The 12Z Euro is a bit of a compromise, but looks too warm initially so it would probably be a lot of rain, as well. The fact that they are all showing an explosive system makes this something to keep an eye on, but I'd be more inclined to buy the cutter solution right now. I don't see blocking yet or much of a western ridge to set the trough in the East where we'd want it. It isn't much, but the 2-4" we could grab on Monday may be our best bet. The FV3 has given us a ton of digital snow this year a week out from systems. I don't know what it is with this model, but it seems to be verifying even worse than the GFS (which is doing quite poorly overall this winter). I assume the difficulty forecasting this winter is the main reason for its poor recognition. Hopefully in the future, with more steady patterns, it isn't a total fail.

Well, we're entering the February doldrums. Remember when it used to be a cold and snowy month? Pepperidge Farm remembers. Anyway, finding something to talk about here... I discussed a week ago how we may be punting at least the first half of this month. I think that's still correct, with a low-snow pattern likely to consume two to three weeks of this month, but the progged warm period may not extend beyond this week. We're dealing with extremely hostile teleconnections, including an AO that looks to spike severely positive for a brief period. A lot may depend on the extent of the MJO's laps around the warm sectors. It does look like - eventually - we'll get favorable forcing out there in the tropics. Perhaps a brief seasonal look of NINO qualities? The MJO may finally head into Phase 8 and beyond. If you believe the GFS, it will take perhaps a week or so longer to get there, while the Euro has a quicker evolution. At this point, waiting a week longer for anything is a dangerous proposition. March has arguably become our new February of late, so it isn't all bad just yet, but I'd say we need things to happen sooner rather than later. The other positive we may get by mid-month is some actual blocking. That's a big if in this winter, though. The one positive for now is we aren't full-blown torching like the last couple years. After this week, we'll probably ride the boundary for a while. Basically, seasonal temps, as we've seen most of the year. All the breaks from seasonal norms this year have been brief. I think the current five days would be the longest such period of the winter. As for snow chances: Friday possible with a changeover situation as we had last week, but like last week, I probably wouldn't expect much. Next week is the transition period, so again, probably not much in the way of snow. There's some slight potential a week from today. The look is convoluted on long-range models, and the process definitely favors a cutter/warm solution, but we could have a cold high to the north that forces the primary south of us. Warm tongue concerns, sure. We might sneak in an overrunning event after that one, say on either side of Valentine's Day. I do hope we can get into something workable before February is over, otherwise I'm tempted to say Phil's forecast may be relatively accurate.

Apologies as I know this is off-topic, but I wasn't even necessarily referring to government intervention. Obviously this varies quite a bit from company to company, and some jobs require showing up regardless of circumstances (medical, police, fire), but I think there are plenty of private companies that expect people to show up even if the world was ending tomorrow. I won't expound much on this as I know this isn't the place, but my main issue is: management needs a bit more compassion and understanding and less rigid employee manipulation. Ideally changes would come from within institutions and wouldn't require external compulsion. CWC illustrates my point exactly, though. As for the snow itself, I think this was definitely an over-performer for the southern areas. This is the rare instance it would have been better to be back in Morgantown, but I think places in and around Pittsburgh got pretty much what we expected in the order of 1-3" all around.

It's not too surprising this event was so impactful despite the little amount of snow. Extreme cold prior to snowfall meant the road surfaces were highly receptive to instant icing, along with the other issue of salt not being effective. People that didn't have to be out this morning should have just stayed home. I find some workplace policies on these issues frustrating. Good thing schools recognized the issues and cancelled.

GFS and NAM look weaker and further south. CMC is sort of in-between, while the ICON and the FV3 both look pretty decent. Given the possibility of high ratios for this snowfall, I could see a surprise 3-5" solution as possible. Maybe not likely, but possible.

Not too surprised at the upcoming warm period. I believe the MJO has a 7-10 day lag period, and it's been camped moderately in warm phases now since the 21st. The AO is doing what it can to offset it, but even that looks transient and is likely to bounce back to positive before too long (as it did back in early December). Other than lack of -NAO, our other big problem is the PNA is now stepping down to negative, and considering how poor the pacific has been this winter, that only makes things that much worse. Given all the other conditions, the AO alone couldn't save us. If the MJO continues to do laps in Phase 6, that's a real problem. I wouldn't expect particularly wintry conditions until that forecast improves. At this time of winter, Phases 8 thru 3 are ideal, and we've barely even touched the cold MJO phases this year (just five days or so in early January). Outside of the active STJ moisture train, this has been much closer to a NINA winter rather than a NINO. I estimate we're in for another two weeks (at least) of this current pattern before we should expect changes. Unfortunately, that burns the first half of February, but maybe we can score something minor on Friday before the positive temp anomalies. Somehow, Pittsburgh is already close to half the seasonal average with 17.6" this winter. They've also recorded a foot of snow this month, which sounds high to me, though it appears we've nickle-and-dimed our way to something reasonable. It's still below normal, but not severely so.

I think this graphic perfectly encapsulates this winter: Every storm has driven a wedge of warm air through the cold. And there's plenty of cold air accessible. Look at the singles and negative readings just north of Lake Ontario. Not to mention two frames before this we have temps in the teens. I won't say this is the worst winter I've tracked through, because it probably isn't, but it is definitely one of the most annoying. A never-ending cycle of cutters and rain storms, with cold air following storms rather than syncing up with a moisture flow. The long range GFS isn't encouraging (very northern stream dominant). The FV3 tries to build more southern-centric coastals, but they are all suppressed out to sea due to the polar air. At this point, it is hard for me to believe the pattern is actually going to change for our benefit. The MJO is still quite unfavorable and really needs to get into Phases 8 thru 3 at this point, but it has been living in the opposite regions. The only thing that could possibly save us is a tanking AO. If that happens (and it's a big if), it could help position a -NAO, which may help prevent cutting systems, but we still need the pacific to improve considerably. I feel like that's the biggest impediment to our snow chances. Because the pacific flow has been generally poor for months now, I don't know that there's a quick fix. I'd say maybe by end of February or March, but by then we're out of prime climo and snow chances. Of course, if the pattern ever does break down, perhaps there's a significant storm during transition.

The more these rain storms occur, the more I think this just isn't our winter. It was 0F last night and is close to 50F today. The atmosphere wants to rain here and that's it, as evidenced by our wettest year on record. This is a harsh pattern we've been set in since mid-2018 probably. If we're lucky, we'll dry out just in time for next winter.

GFS has had this weird evolution. I don't think we're likely to know anything until the first threat or two passes through. That quasi clipper becomes a massive cyclone over Maine while it is separated from the rest of the northern flow. The second low behind it then becomes a southern slider of sorts that taps into gulf moisture and pulls energy from the west coast. Very bizarre looking to me. That said, the setup provides some decent blocking and appears to have potential to dig further (thus intensify rapidly). A couple inches for this changeover event on Thursday looks possible, maybe a clipper on Sunday, then this one on Tuesday. Certainly an active period. Hopefully it produces for us.