OHweather

As has been mentioned the WAA thump in IN/OH will be interesting. This is not unheard of in these parts but is pretty uncommon... The temp profiles would warm quickly enough to preclude much accumulation if not for wet bulbing/dynamic cooling. The dynamics are impressive (especially as you head east into OH) with very strong upper-level divergence in the right entrance quad of a strong jet streak, a deep layer of strong isentropic lift on a 70-80 kt LLJ, a tight thermal gradient/strong fgen, high PWATs advecting in and steep lapse rates above the mid-level warm nose providing for borderline convective instability. This will combat the change to rain for a time and allow for heavy rates while it's snowing. This has some similarities to the November front end thump on the East Coast that was wildly underpredicted by humans (though modeled embarrassingly well) but is toned down a tad (it produced a widespread 6-12")...I think some 6" lollis are doable in the heaviest band into OH and it will fall in a short time.

Ha, better than what I glanced through last night. The 12z NAM was more cross-hairy in central OH later tonight than the 0z last night. It's almost certainly overdone, but there's a pretty good signal for an advisory to borderline warning criteria thump (3-6")...question will be where exactly. Thermals are iffy but evaporational/dynamic cooling should be enough for a time and rates will be there. NAMs are both north of most guidance and suggest north of I-70 does best, others are a bit farther south.

I think a swath of moderate snow (3-6”) is likely across a good portion of central and southern Ohio... All signs point to a boatload of QPF with outstanding upper level divergence, high PWATs advecting in, very strong low to mid level warm air advection and isentropic lift, and strong frontogensis. Question mark is obviously ptype. With plenty of room to wet bulb cool as the precip arrives and what should be very strong lift, think it’s likely most areas north of the Ohio River flip to a few hours of snow...though it may initially start as sleet and surface temps won’t be that cold. Strong lift will slow the advance of the mixing for a time, though with how strong the WAA is it will eventually overwhelm, so it may be hard for anyone to see more than 4-6 hours of all snow. Given the sensitivity to temps and rates here, hard to be very confident in big snows for a large area. I think there’s enough juice for warning criteria somewhere but it may be the exception rather than the rule. The low and mid levels aren’t that cold so it will be a wet snow. I’d like to see model soundings show a better “cross hair signature” (lift in the snow growth zone) for better confidence in 6”+ snow. Right now the idea of a few hours of moderate to heavy QPF as snow but with questionable ratios limits how aggressive I can go to 3-6”, but it could be an exciting 3-6” and there is some boom potential. My guess is the jackpot may be central and east central Ohio. Either way it’s tricky and though I’m fairly optimistic for someone to get a decent thump, trends during the day Tuesday leading up will make or break it.

Yeah, but it can snow ahead of an upper low. It eventually goes to something else, but that intense WAA running into a stubborn high/cold air can wring out a good amount of precip. The Euro does not count sleet or ice as snow...it used to years ago but does not anymore. The NAM does count sleet/ZR as snow 10:1 snow, though other products such as “positive snow depth change” don’t and show accumulating snow with this. It’s easy to take the under on the 8-9” of snow the Euro spits out...but with a push of moisture and cold in front of it some sort of snow isn’t hard to envision. N NJ got 8-12” of WAA front end thump in November with the upper low to our west, it can and does happen (though often not to that extent).

Yeah. One of those where I’m not excited, but it’s pretty easy to see how it happens and more than a couple Euro runs have hinted at it. You guys are a good storm away from clinching an average or above snowfall winter somehow and as much as March snow is undesirable for some, it’s not like there’d be nice weather otherwise...so front end warning thump snow would be fun.

Right, big surges of moisture running into a high pressure and cold air never produce snow. I wouldn’t lock this one in yet but stranger things have happened. I think you guys should root for a faster solution as the high eventually retreats, so the more precip before then the better.

A little bit surprised that there's a thunderstorm heading towards Indianapolis right now. If any of you get hit by that batch of precip certainly let me know what's falling, it'd be helpful. My guess based on CC is it's a lot of sleet or small hail for the city and aggregates north.

Have to disagree that the MJO hasn’t mattered this winter. There have been two relatively quick passes through the “cold phases” of the MJO in the last 3 months...one from the last few days of Nov and through the first week of Dec, and another between Jan 5-12. Both were accompanied by cold during or shortly after. Meanwhile, we’ve had two slower and higher amplitude passes through the “warm phases”...one mid Dec through the first few days of Jan, and then another mid Jan through now. We’ve (not uncoincidentally) seen occasional warm shots in both periods. Strong phase 4-6 MJO is not what one would expect in a Modoki El Niño and likely helps explain the I-95 fail so far. If we get a slow and fairly strong phase 8-1-2 pass over the next few weeks it will shake up the pattern, and would be easily a more favorable tropical forcing look than we’ve had the majority of the winter. Whether that results in legit snow for Ohio next week I’m not sure on (suspect it ends up being a modest event Sunday then maybe some mixed crap Tuesday) but it would at least keep the door open for another few weeks. The subtropical jet looks absolutely super charged later Feb and early March so if we can settle into a relatively cold pattern there will be chances.

ORD and DPA can wet bulb into the upper 20s when it comes in given their dew points...ORD in particular may not hang on for THAT long but it will take some time to warm from the upper 20s to above freezing once removed from the lake and most significant urban influence. With the rates there will still be accretion issues where it's not that cold though...tough call for where more significant icing starts but it might not be that much farther W/NW from ORD. Ironically I still like the Detroit area and especially just N & W better than Chicago for warning criteria ice (though someone in IL probably gets 0.25" of accretion).

It'll be interesting to keep track of this...through 5z the HREF mean is not aggressive enough with the southern push in the Plains, but is a little too quick with the eastern push into WI/IL.

Yeah, you start low to mid 20s with dews in the 10s advecting in, with no big "warm" lake immediately to your east. Detroit likely won't get above freezing until the vast majority of the precip falls if at all, and there will be a period of good accretion initially. I think warning criteria ice accretion is pretty likely, though will obviously have to watch obs and make sure that cold push gets in there as modeled...though it likely will given how cold/dense the airmass is. Same interesting questions about pavement temps and also warm drops/heavy rates, though if your air temps are 22-25 when precip starts (along with a deeper layer of cold at the surface) you should have a period of good accretion off the bat on trees and also significant travel impacts. The 0z HREF is colder than my initial thoughts for Chicago/IL. As OUN's AFD above indicates the higher res stuff is likely leading the way with the low-level cold air seepage. The HREF routinely kicks all other guidance's ass (badly) with CAD here east of the Appalachians...this isn't CAD but if it's leading the way so far it's likely worth giving more weight. It has easily over 0.25" QPF falling before temps get above 30 just west of Chicago (and would be problematic even south of the I-88 corridor). The short duration, winds off the water limiting the supply of cold/dry air to offset the latent heat release of the icing and warm drops/heavy rates still give me pause for IL, but if the colder guidance is right there will be a narrow corridor that gets a decent accretion with some tree damage. If you're getting 0.25-0.50" QPF with temps below 30 and some more with temps 31-32, even if it's pouring and not accreting as well as it could that's still a lot of QPF falling at a cold temp as ZR...would be pretty surprised if there aren't a few counties west of Chicago (and maybe Cook for the NW corner) that end up under a warning...but wouldn't be too ambitious expecting significant impacts where it's sitting at 31-32 on the southern edge.

That's a good point. It will certainly be interesting to see what happens. I think as is usually the case that accretion will be less significant/widespread than modeled due to a few negating factors, but there should be a narrow zone that is cold enough and gets enough freezing rain to be more problematic...just hard to avoid with the amount of QPF and some areas starting in the upper 20s.

There are so many variables to consider when figuring ice accretion and impacts...including air temp, antecedent conditions/ground temps, rain rate/drop temperatures, any other p-types mixing in. For road impacts, air temps, road temps, and rain rate/temperature are all important...and stuff like this can be tricky. For instance here in NW NJ, it was low 50s and sunny yesterday and 60 and sunny today. But, our ground is still frozen and wet pavement was starting to freeze on my walk home with an air temp of 37 degrees. It helps it's radiational cooling but is still impressive/surprising. I know road temps in IL and IA today somehow got into the 40s, but you guys had two mild days after a brutally cold stretch, I'm guessing the ground is still mostly frozen...and it will be below freezing for about 24 hours before the ZR starts. There will be some sun tomorrow so it's tough to figure pavement temperatures, though they likely won't be overly warm...likely awfully close to 32. The airmass pressing in is decently cold and dry, but winds will be E when the ZR is ongoing and aside from the near shore waters Lake MI is well-above freezing. Inland locales may hang on to 29-31 degree air for most of the ZR but the city and lakeshore will likely warm to 32-34 quickly owing to warm temps just aloft being dragged down by the heavy rates and a lack of sub-freezing air advecting in, due to the surprisingly warm waters in the middle of the lake. More than a few miles inland, mainly in Dupage, western Cook, inland Lake, McHenry, Kane, Dekalb (can extrapolate WSW a bit farther, and also perhaps into southern Walworth, Kenosha and Racine WI) there will be a narrow corridor that starts in the upper 20s when the ZR arrives and will take time to warm...and may not ever get above freezing well north of the surface low track. The southern edge of this will be tricky because the warm layer is impressive so the drops will be warm with heavy rates...this will not accrete well if it's at or only slightly below freezing. This is bracketed on the northern side by more sleet than ZR. Given the strong isentropic lift/WAA and some modest upright/convective instability during the heaviest precip, to go along with impressive PWATs of over 1", I can buy 0.50"+ of QPF (though over 0.75" will be a stretch IMO). The lack of good cold/dry air advection and heavy rates, along with short duration, are arguments against a significant ice storm. Given the heavy rates/warm drops on the southern fringe along with short duration and marginal surface temps, the modeled southern edge of the ice will likely be way too aggressive...I'd expect the more significant accretion to start 10-15 miles north of wherever the models have it, with the southern edge where it's marginal probably seeing a little glazing on some surfaces but much milder impacts. This leaves a narrow corridor before it's more sleety to the north into WI (which will likely have its own travel impacts). In that narrow corridor, drops won't be quite as warm due to deeper low-level cold and road temps may be cold enough for icing. If the "normal" ice to liquid ratio of 1:2 is realized there would be enough QPF for a narrow corridor of tree damage, though with heavy rates and temps not that far below freezing the ratio may be worse than normal. I think it's a narrow corridor that may actually see a legit ice storm with more severe travel impacts and tree damage...to the south, the heavy rates/warm drops along with marginal surface temps won't accrete well on trees or roads...this also goes for the city of Chicago and most of the immediate IL shoreline. I like LOT/MKX not hoising an Ice Storm Warning yet...if they do (and I'd guess they will eventually if the expectation tomorrow afternoon is still for 0.50"+ QPF falling at or below 31 degrees) it will only be for a few counties.

I think there's plenty of reason for optimism over the upcoming 2-3 weeks. The GFS and ECM suites have drastically different evolutions with the MJO, which causes large differences in their medium-long range patterns... The EPS takes the MJO into phase 8 quicker, while the GFS loops it through phase 6 and 7 at a high amplitude before eventually translating it east later in the run. This results in the EPS being colder overall through the run. Both suites pop a -EPO in the 6-10 and try lowering the NAO, while the GEFS becomes more zonal in the 11-15. Both would support a sharp gradient across the Midwest with snow opportunities, though the EPS would open the door farther south earlier. May be a situation where a strong storm cuts some (though IA, Chicago, Detroit would still probably see snow even with a stronger storm) while a weaker wave favors farther south, given the -PNA and meager looking -NAO at the moment on the smoothed ensemble means. A higher PNA or stronger -NAO would act to shift even the stronger storms farther south. I don't think the GEFS evolution of the MJO is right, and it still suggests snow potential, but it will be interesting to watch. A prolonged -EPO was a big feature in the 13-14 and 14-15 winters even with a neutral to positive NAO...and if we see it again, there certainly will be more cold/snow given how active the pattern remains. Regardless of the MJO, both suites show higher than normal pressure over eastern Asia, which is a positive East Asian Mountain Torque and would favor an extended Pacific jet and Aleutian low, which gives some confidence in the EPO being largely negative for the foreseeable future. The PNA might come down to MJO evolution more, while the NAO remains a crapshoot this winter.

The EPS isn't fading the -EPO in the long range, FWIW.

4.6" at CMH

You certainly make valid points, and I should keep the venue in mind here. My point wasn't that there's technically "nothing" to complain about, but I was legitimately surprised by the tone in here for the reasons I mentioned. I agree there hasn't been much memorable winter weather in central/southern Ohio lately (13-14 and 14-15 were good winters at least) and honestly climo seems like a small win, so I can understand general frustration. The timing just seemed odd to me, though given how much billing this winter received coming in I think it just set everyone up for disappointment. The ensembles already look a lot less torchy in early Feb with the weenie range GFS occasionally showing some nice W-E moving systems now, and it might even snow some later this week a little (plus maybe some arctic front snow squalls on Wednesday)...not that I'm excited for any particular period yet, but I stand by my point at least that there's more winter to come, it has snowed at least a "fair" amount lately (Jan 12-13 was arguably memorable for parts of southern OH, Jan 19th sucked in its own way but was decent in a lot of the state, though the rain getting really far north tainted everyone's opinion on it), and it is still not "late." I can respect that everybody is going for different things and if you want a long, spectacular winter that ship is sailing on this one. But in terms of a snowy stretch, maybe a decent storm or two, I think there's plenty of time/potential for something like that even if it isn't making any record books.

The front edge of the snow in NE IL is still saturating the dry low-level air, and lift in the DGZ improves with the heavier precip in a few hours. I think between the two flake size improves over the next few hours, though with a rather narrow DGZ and best lift focused JUST below it ratios probably aren't out of control...probably a 12-15:1 as opposed to the typical clipper 18 or 20.

I definitely think it would have to be a rather rural, sheltered site that's preferably in a relative hole to attain, as it's simply hard to do. There was a Wunderground station next to a ravine against a cliff in extreme NE OH that tagged -39F in February 2015 (would've tied the state record if an official station) in a slightly less impressive airmass...so I think it's doable, but it certainly needs to line up perfectly to happen. Ideal radiating conditions will be needed, and seem attainable, so we will see.

It's been disheartening at times to watch your snow amounts come in over the last few years, they've been underwhelming nearly every storm, so I can understand your frustration on a larger scale. And living in Ohio my whole life until a few months ago, and spending a few recent winters in SE Ohio, I certainly know what it's like and know that other than 13-14 and parts of 14-15 it's actually been a pretty lackluster decade in Ohio. The 77-78 analog is funny because it was a decent analog for many reasons, and the recent evolution could've been much more exciting had we gotten a couple of shortwaves to phase better. We got extreme amplification at around the same time as that winter and driven by similar larger scale patterns (weak El Nino, strat warming event), but it didn't quite fall that way in terms of storms working out. But, much like 09-10 in the mid-Atlantic, the odds of getting a winter with similar drivers to work out that well again just aren't great, they're historic for a reason which you alluded to. 77-78 weighed rather strongly on my analog list, but other years that made it in weren't very exciting (06-07 a recent poor winter that was on the list, same with 94-95). There were also a lot of close to average, a bit above or a bit below winters in there. I don't want to polish a turd. It may be easier for me from afar, I see it as "wow, after a bad start most of Ohio is catching up to their averages decently, and I see another period of cold/snow on the horizon" while some here are going "after a bad start, we're warming back up after 2-3 weeks of cold in a decade that hasn't been good for us." I'm not living it this year (not that it's snowed much here yet either) so maybe I don't quite have the same perspective. We can argue how to interpret what's happened so far all day, I just believe that given a gradual but definite pattern shift over the last few weeks that is still (IMO, for a number of reasons) evolving that this little 2-3 week shot isn't close to being it. If I didn't see signs of cold air returning I'd be much more understanding of wanting to punt to next winter. The Euro weeklies honestly haven't been reliable this winter, but are also quite cold/active with a similar pattern as the CFS for roughly the same time period. Given continued gradual downwelling of the stratospheric warming event contributing to a -AO and likely -NAO as tropical forcing tries to line up again in early February, there is support for their general forecast IMO. The trick that I still haven't figured out yet is, do we get a two week shot in February and warm back up, or is it a bit more prolonged? I'm leaning towards it being prolonged as once patterns influenced by a stratospheric warming event setup they usually are persistent, but that may make the difference between what would be a very meh winter and something that's at least closer to average.

I’m curious to see what happens Wednesday night for obvious reasons. The coldest 925mb temps are during the day Wednesday, with weak return flow developing by Wednesday night. But with a clear sky, fresh and deep snowpack, and still quite weak gradient there should be a corridor that tanks with cold spots easily dipping to -30, maybe a few -40s in some sheltered areas? Dew points will be near -30 and it’s not hard to drag them down when it’s that cold. My hunch since this is radiation driven Wednesday night that the coldest is just west of Chicago, though the lows Wednesday morning will all be advection driven so might do quite well in the city. It will be interesting to monitor any attempt at WAA and high level clouds as mentioned. At the moment both look to be too late for parts of eastern IA/northern IL into WI, but possible flies in the ointment for all time record cold. Have to imagine if the boundary layer flow is less than 8 or 10 knots it’d quickly decouple over the deep snow pack Wednesday evening.

That convective looking band the models keep hinting at ahead of the cold front over extreme eastern IL into IN and southern MI looks interesting. Some decent PVA and lapse rates are almost steep enough for upright instability/CAPE through the DGZ. If it’s all snow (which it probably can be at least farther north?) it might be quite exciting for a time.

Since you asked, I do not agree with GRR's decision here. I think IWX boxing them in with a warning in their SW MI counties despite forecasting the exact same amounts of snow sums it up well. I am not sure why their advisory expires at 7 PM Monday when LES kicks in quickly Monday evening. GRR's southern counties will be getting heavy snow/wind during the rush with temps remaining very cold until later morning, worst conditions during and just after the rush. Then unlike northern IL they see squally lake effect snow showers with gusty winds and falling temps kick in immediately behind the storm Monday evening and lingering into Wednesday, which I think will just cause roads to just become snow packed as the cold weather sets in. The lake effect will also be good at reducing visibility as the cold lowers the DGZ below the clouds, resulting in a lot of small flakes falling with gusty winds. Not great for heavy accumulations but still will impact travel for an extended time in conjunction with winds chills getting close to their warning criteria. This all shoots down "how long it takes to get back to normal" criteria they mentioned earlier in the winter. Amounts hit criteria anyways. And it's high impact and prolonged. So I'll just leave it as I don't agree with GRR. It should probably be a long duration WSW through the day Tuesday at least, IMO.

A 6” fluffy synoptic snow falling over 10 hours with no wind on a Saturday can probably slide with no warning, but no mitigating factors here and a lot of compounding ones. I know MQT factors in ratios and may grudgingly put out an advisory for 6” of fluffy upsloped LES but will warn 6” wet synoptic. At least that’s what a tv met up there once told me. Hard to come up with flexible criteria that make sense for any possible given storm, but I don’t love the rigidity of the current criteria. Too many factors other than snow amount over a 12 or 24 hour period.

You personally didn't cancel anything, but the overwhelming tone was quite negative including from yourself. I never said you guys should be "grateful" for anything, but was quite surprised by the tone (I just happened to glance and see if anyone got snow last night) given the last two weeks have been quite a bit better than the 6 weeks prior and it's still early, and multiple indices are favorable moving forward. Like I said in my previous reply I can't tell anyone what they like or don't like...just was surprised at all the pessimism and certainly inquired as to why it's suddenly the feeling here. If you're going for 40-50" winters every year (and I know you and most who have been around for a while aren't) then sure, this winter won't get there, but there's still plenty of time left for snow and there has been more than dustings of snow recently. Hopefully you guys get something decent in February and make this all a moot discussion.