Hoosier

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A good one would be will MSP get to 60" before ORD gets to 20"? Given the overall look in the extended, it's a non-zero chance that ORD gives that one a run.

MSP picked up a tenth today, so latest numbers are MSP: 52.6" ORD: 6.2"

Today's 1.5" at ORD is officially the first January calendar day snow of 1" for Chicago. This is the deepest into January for the first calendar day snow of 1" since 2017, which had no calendar day snow of 1" in January.

I'm not sure it's warm ground per se. As mild as it's been, there's been hours/days with temps below freezing. I think the more likely culprit for the melting is the marginal temps along with just enough solar energy getting through.

Izzi with the afternoon afd for LOT .LONG TERM... Issued at 300 PM CST Sun Jan 22 2023 Tuesday through Sunday... No big changes in forecast reasoning or guidance with the 12z suite of model runs. Primary highlights of the long term portion of the forecast include: * Accumulating snow likely to overspread the area from south to north overnight Tuesday into Wednesday morning. * Should be north-south gradient in snowfall accumulations across the CWA, with current data favoring higher accumulations south. * Intermittent snow showers likely to persist through the end of the week with threat for swaths of light accums and hazardous travel conditions. Water vapor imagery early this afternoon shows a well defined southward moving upper low over the Intermountain West that will be our weather maker mid-week. Secondary player in our mid-week weather is a strong Pacific storm system over the Gulf of Alaska that is progged to ride the polar jet stream across western Canada before digging south into the northern Plains later this week. The 12z operational runs and their respective ensembles really didn`t depict any changes that graduate from the noise level to something that is noteworthy with the mid-week system. The 12z operational runs of the GFS and ECMWF are actually in remarkably good agreement with each other through 12z Wednesday. Later Wednesday into Wednesday night, the operational GFS does bend the surface low track back a bit farther west than most of its ensemble members and the ECMWF and EPS. As far as sensible weather conditions go, really no meaningful differences between these models, both have the swath of heavier snow just to the south and east of our CWA. However, both also have a broader area of lighter snow blanketing most of our CWA farther to the north and west of the band of heavier snow than is typical with most of these mid-latitude cyclones. This is likely a result of constructive interaction with the aforementioned northern stream shortwave trough digging south just to the northwest of the southern stream cyclone to our southeast. Current model QPF for late Tuesday night into Wednesday combined with the somewhat marginal thermal profiles, looks to favor a 1-3 or 2-4 inch type snow along and north of I-80. Farther south, particularly across northwest Indiana, if current runs were to verify, accums would get solidly into advisory level criteria. Some guidance is showing some enhanced QPF over northeast IL associated with some lake enhancement, particularly Wednesday afternoon and evening. Guidance is in good agreement that air temps will probably be a hair above freezing by then, and if today is any indication, snow may struggle to accumulate much during the afternoon. In addition, lake effect parameters appear quite marginal for lake enhancement with shallow tops to the lake induced convective layer and weak instability owing to the lack of any strong push of cold air. This makes me somewhat skeptical of the models showing significant enhancement to the QPF as a result of the lake. Finally, while there is (and has been for a couple runs) pretty solid model and ensemble agreement in the handling of this system, it is still quite plausible that guidance could change. While guidance never really truly phased that northern stream shortwave with the cut off low over the southwest, there certainly seems to be some interaction with the northern stream wave perhaps pulling the southern stream wave a bit farther north, and this certainly seems to be resulting in a broader snow area on the NW side of this cyclone. Models are notorious for struggling both with the movement and timing of cut off lows (like the one digging into the southwest) and also can struggle at times handling the interaction of northern and southern stream waves, like is progged mid-week. All of this to say, that current strong model agreement doesn`t necessarily equate with high confidence in the forecast. If the timing or amplitude of either wave changes much, then the degree of interaction could change. Less interaction could result in a sharper cut off to the snow on the northwest flank of the system, or a track farther south could lessen our snow amounts. Conversely, more interaction/phasing and the heavier snow with the TROWAL could result in higher impact accumulations farther north into our CWA. Beyond this southern stream wave`s snow, maintained/nudged up pops Wednesday night into Thursday associated with the northern stream shortwave. Combination of forcing with this trough and instability resulting from the very cold air aloft (-33C at 500mb), should result in a pretty favorable set up for at least scattered snow showers. Some indication that we could see a brief break in the snow shower chances (at least in these latest runs) Thursday night, before the next northern stream trough moves across the region Friday. Guidance remains rather inconsistent with the handling of the individual waves, and to an extent, with the overall pattern by Friday into next weekend. Given the lower confidence, made no changes to NBM, which does have snow shower chances with the shortwave Friday then potentially another more impressive system later in the weekend or early next week. - Izzi

Bo wouldn't even realize it snowed.

52.5" as of early today. They may have squeezed out a pinch this morning.

I could see transient 10:1 or a bit better in some banding. Otherwise I would be counting on a little lower.

With today's snow, ORD has topped 6"

Never heard of this wxsphere until now. Looks like the place is hopping though.

My brain hurts

Yep, got screwed here.

I'd caution about the 10:1 maps. This could be a case where those are overinflated. Marginal thermal profiles suggest some areas coming in under 10:1.

I'm like obsessed with this northern stream stuff now 12z Euro vs 00z Euro (which has a farther south precip shield)

What's medium dog in your eyes... like 10-15"?

Certainly fits with what we've all been feeling for a while -- winter has often had a hard time getting off the ground.

Do you have any opinion on my other post about the model differences (namely GFS vs everything else) in handling the stuff diving into the northern US from Canada as a possible explanation for the GFS lack of qpf farther north?

00z GFS should at least take a little step toward the other models.

Look at the differences in the Plains between the 18z GFS and 00z NAM

The GFS is pretty much on its own with the suppressed precip shield. Like I said earlier, I think it could be in the way it handles the wave coming into the northern US vs the other models. I'n not sure what else it could be.

Is this March/April? We shouldn't be fighting to keep temps below freezing so far north of the surface low in the dead of winter.

The positive thing is that the GFS is pretty much by itself with its handling of the northern end of the precip shield. Hopefully you can at least pull an inch or two there.

Wait, you are optimistic?

Thanks. As others have said, don't expect particularly good ratios with this. I actually think we could be a little under 10:1 for a while.