OHweather

This may be one of those rare setups where it inches a little colder closer in. The GFS put the "L" over KY, but has a pretty strong little surface circulation up to just NW of Wheeling, so I think that's why it pulls more warm air in. Canadian is north of the UK's low track and just misses crushing Columbus. The UK is a little more compact with the low. The 12z UK was rather snowy, will see if I can spot the 0z snow map floating around anywhere before I go to sleep. The GFS takes the 850mb low well northwest of its surface low track, a bit NW of Columbus to just south of Erie. The CMC looks a little bit more stacked. The 850mb low is a good indicator for how far north mid-level warmth will come and the GFS was a good bit farther NW, despite where it put the surface low. I ultimately don't like the GFS's surface depication at all, looks like it may be having convective feedback issues and it's known to be horrible with low-level temps.

UK met looks like it’d be a crush job for central/maybe southern OH. Crudely looking at the 24 hour plots it’s in the low 990s over KY and probably gets to near Charleston before transferring to off the Delmarva. The GFS and CMC did inch towards less phasing this run though the changes weren’t huge. Euro will be interesting...

The reason for the sort of SE trend on some models has been due to the polar vortex being focused a bit farther east, making it harder for the southern piece to sneak ahead of the western lobe of it and phase, and also causing more confluence in the height field over the NE and a stronger surface high. The GFS and CMC were faster with the southern piece and still phased, while the Euro, NAM, and UK lagged and didn't phase, hence their less impressive solutions. Given how strong/pressing the polar vortex is, I'd definitely be worried more about suppression than mixing, that's for sure. The 0z GFS and Canadian inched towards a later phase, but changes were borderline noise level...will be interesting to see if the UK and Euro hold. My initial call for the Cleveland/Akron area would be 5-8" but with some more upside if there's an earlier phase. I think even if it doesn't phase well the over-running snow would be decent (and probably good ratios) so you should see a decent amount up there. Would hate to have to put out a number for Columbus because they really could go either way. Because NW NJ dams cold air well and the airmass to the NE is frigid, any QPF that isn't snow here will be sleet/freezing rain. So I am selfishly hoping for the slightly more suppressed route, as exciting as 1.50"+ QPF as "not snow, not rain" would be.

I think the PV and high pressure put a cap on its northernmost potential which is why it redevelops, but the 12z GFS and CMC phase it early enough to start cutting before it runs into the wall to its north. I’m not quite sure if central Ohio can get away with an early phase and stay all snow and get over a foot...northern Ohio can. I think you want to root for a weaker/later phase which would cut down on max potential but prevent that cut before it redevelops. I still think there’s enough juice for 8-12” even with a sloppy phase that keeps the low farther south. Curious to see what the Euro does in a little bit for sure.

12z UK takes the primary to just east of Charleston...not sure on temp profiles.

This kind of reminds me of the storm last January 12th where the models really blew up the storm and drilled northern Ohio, but a progressive northern stream caused it to trend weaker/less phased 3-4 days out and central and southern Ohio got a moderate storm. Different setup here for sure, but same kind of result with negative northern stream influence due to the polar vortex preventing a good phase and wound up solution. Given the great thermal gradient/jet/abundant moisture I could still see an 8-12” swath even with a less amped solution...given the trend I-70 is definitely in play for that.

I would say be careful, you have a fair amount of margin for error before mixing comes into play and I don't think that becomes a concern north of Rt 30, but we've seen worse trends. Given that mixing is a long way from being a legitimate concern and it'd have to trend considerably weaker (when the overall trend the last several cycles has been more amped) this one looks pretty good for northern Ohio...5 days to go...

Yeah, the GFS especially has slowed down the southern stream shortwave, the Euro has been a bit slower overall with it. It's interesting what that will do, because if the first lobe of the PV swings by in front of the storm it should shove the thermal gradient farther south, but if there is a phase with the second piece it may eventually cut a bit anyways if the first lobe of the PV gets out of the way fast enough. If this can phase with the PV it'd be quite a storm...I tend to lean against that, but it is a possibility if the slower southern piece trend continues, and if he second lobe of the PV dives aggressively enough. I suppose the other option is it phases with the second piece kind of late which would be more beneficial to the eastern lakes and Northeast.

I’m pretty hype for this one. This seems classic for a lot of the sub. Big lobe of the PV over Hudson Bay setting up a tight thermal gradient/strong jet, strong moisture laden Pac shortwave riding west to east along the gradient. Should be a good amount of QPF for someone with ratio boosts in there as well. Obviously questions on how north it gets...the PV will have something to say about that...but could see how this is an along/north of Ohio River storm or more of a southern Great Lakes storm depending on where that gradient sets up. Ensembles are locked and loaded with 6”+ (perhaps much more) potential wherever the snow sets up. The one thing that could prevent this would be the PV being too suppressive...I doubt that happens but is within the realm.

The secondary flare up tonight with the upper low appears to be coming to fruition over IN and will head east...should be a nice boost south of I-70 into Sunday morning. Not a bad storm to break out of a funk with.

Casually peaked at radar and some storm reports through the day...nice to see the rare WNW to NW flow event that isn't short on moisture.

In regards to the last point, a majority of my analogs had a SSWE or at least a significant disruption that in most cases resulted in a decent period of cold after. Many of the analogs were rather mild for December. A +ENSO, low solar, lingering -QBO in the lower strat all are going to favor a SSW being more likely than otherwise with all else being equal...so while it is an important piece to getting the anticipated shift to a blockier regime for the second half of the winter, outlooks that had a colder second half of winter in all likelihood banked on it occurring. After a cold November and start of December we're getting a fairly prolonged mild pattern right now, which just feels odd and I think is causing both an increased level of panic and what seems like straw grasping by some as they point to a SSW to turn the winter around...but at the end of the day it was kind of expected to go like that, so it's more of a "be patient" than a "the ship is sinking, but oh look maybe a SSW might save us". Whether it is just an "adequate" pattern for the eastern half of the US or a "holy sh*t!" pattern probably remains to be seen, though if we can get the tropics to align with the high latitudes in a few weeks it can certainly make turn towards the latter for later January and February.

It's funny...a positive EPO was modeled for the middle of November and that didn't pan out at all, instead, we went back to the seemingly new normal this decade of a large ridge up there that gave most of the eastern US a cold second half of November and first part of December. And completely blew my generally mild November call... The very positive EPO for the middle and latter portions of December that was modeled as early as around Thanksgiving isn't going to fail. When I saw the ensembles last week retracting the Pacific jet the last 10 days of December and beginning to really pump the ridge over AK I thought we'd go back to the familiar AK ridging pattern with maybe just a 7-10 day warm up, but I think in this instance the intensity of the current +WPO/EPO and unfavorable MJO is causing this milder period to pan out much closer to conventional wisdom...usually a massive +EPO/WPO is bad for sustained cold for most of the CONUS and takes some time to overcome, and that appears to be the case here. With that said I do think this will be a delayed but not denied situation and is quite in line with many winter forecasts highlighting the second half of winter as the colder half. The MJO will likely pass out of the unfavorable phases by the middle of January and a fact that many wish to forget is that SSWs usually have a lag effect as Ricky has alluded to...it's usually at least a week or two before tropospheric impacts are felt...that would put us around the second week of January. Remember that a massive torch occurred in conjunction with last winter's SSW before we fell into a colder/blockier pattern a couple of weeks later in March. I think the potential for both the tropics and stratosphere to work together could cause a wicked cold pattern at some point later January into February, though let's make sure we get a SSW first (it looks fairly likely, but it's still pretty far out). In all likelihood that would eventually suppress things too much for much of this sub-forum's liking, but is still a few weeks away. In the meantime, the MJO passing through phases 4-6 and a drop in the AAM (note the large low dropping down east of the moutains in Asia, that's a negative mountain torque that will drop the AAM some) actually argues for a bit of a La Nina look the rest of this month, with an attempt at a SE ridge as the ensemble means want to show. So there could be a conducive storm track for the Midwest and Great Lakes through the rest of December and into early January, but the cold will generally be iffy so we'll see how much of it ends up as snow.

If the PNA is initially neutral or negative (as the EPS in particular shows) when the EPO drops, have to think that may favor a window for possible wintry weather in the Midwest before it gets too suppressive. I suspect the East Coast might have to impatiently wait through the week of Christmas for better snow chances along I-95, though I still think we’re recovering from the mid November coastal/fiasco anyways.

This isn’t one of those “it may not register on the MLCAPE maps but look it’s 100 J/KG 0-3 km CAPE!” events we get in December...legit CAPE to go with winter dynamics. Was surprised to see that when I checked the mesoanalysis.

Yeah, wherever the best band sets up could still see a few inches as winds don’t move a ton, I just don’t think it’ll be that intense. Winds are roughly 290 and reasonably strong so I certainly think the Cleveland metro and southern Snowbelt should see something.

Tonight-Wednesday's leg of the event doesn't look as impressive for NE OH as yesterday when I looked...looks like the Euro idea of keeping the deep moisture farther east will pan out. There's a little shear but it's a reasonably well-aligned WNW flow for quite a while through Wednesday afternoon that isn't too strong with just enough instability and inversion heights of 5-7k feet, so there will still be accumulating snow probably from northern Lorain County points east, but I just don't know if the intensity will be there for more than a broad 1-4" of additional snow, focused wherever the convergence band develops and maybe in the higher terrain of northern Geauga as well. NW PA still gets into the deep moisture with a longer fetch and more terrain, so additional amounts in eastern inland Erie County will still probably justify the warning, especially since some of those areas already have 6-12" and will probably get that much more...though west of I-79 there will likely be a drop off somewhere to much more pedestrian amounts.

Looks like two shots for some snow the next few days...first Monday night into Tuesday morning with some initial wrap-around and lake enhancement...my impression is it's 2-4" in the higher terrain of Geauga and 3-6" for the higher terrain of Erie PA and SW NY through Tuesday afternoon...it's an ok but not outstanding setup, synoptic moisture decent but winds rather westerly and instability limited. So there should be accumulating snow in the usual spots, maybe pushing advisory criteria for some, most likely in parts of Erie County and the Chautauqua Ridge. The next period is Tuesday night and Wednesday when the models drop another vort max and good moisture through. The Euro is more of a clip job for NE OH while the NAM would be very good back into NE OH. With a WNW wind, colder temps, and longer duration, that's the window that could produce a substantial accumulations perhaps worthy of a warning...highest confidence again in the higher elevations of NW PA/SW NY, though if the NAM is right (and it's only a small shift west for the Euro) that could get as far west as the higher terrain of Medina County. A prolonged lake enhanced event with decent ratios, upslope and broad shoreline convergence with a WNW wind, and good moisture and instability would do quite well.

That area will get back into better snow as the deform pulls east over the next few hours, but it will be an unfortunate local screw hole with lower totals than surrounding areas...always seems to happen somewhere.

That's likely it. A lot of the higher res models had a little "dead zone" of lower totals between the best deformation currently over N and W IL and where the WCB is running into the CCB over NE IL.

I was a little out of the loop Friday and Saturday so I can't comment specifically on how the forecast played out for their CWA, but it seems odd for them to come up with the reason they gave to not issue a warning when they have criteria amounts in their forecast...certainly a higher impact with a wetter snow, gusty winds, and rush hour timing too. I can see roadways not being covered in deep snow, but it'll still be quite slick when it comes down with visibility issues and probably some downed limbs and such too with the wet snow and gusty winds.

I count 4 or 5 legit factors pointing towards needing a warning (not to mention the criteria being straight up hit in some spots) and 1 factor that GRR has invented arguing against it. This coming from the office that started the push to get rid of LES products several years ago because of how "confusing" they were ( ) to all of the people who use their products. Oh well. This is a hell of a storm so hopefully those getting hit can enjoy it. Chicago has done well with big dogs trending to them this decade, though the warm lake will hurt downtown on this one.

Yeah, that band got amazingly stuck.

I suspect a better band will flare back up within an hour or two as the rather sharp trough moves across the lake...it won't be 2" per hour like they saw from Erie to Dunkirk this morning but should be moderate at least. The question for some of you will just be how far south it can get.