RCNYILWX

The Crib has been bouncing around a lot. I think that one is taken farther underwater than the shore reading, which is taken at the Jardine water purification plant. Since the lake gets highly stratified is less windy period and it hasn't been all that windy during this cold stretch, that might help explain things. The surface layer would cool very quickly and ice over while the depth at which the temperatures are taken wouldn't have much time to cool in such a rapid ice up, as you would have kind of opposite of summer when surface is warmest and cooler layers below. The ice itself would insulate the layers below, which is what snowpack does to somewhat limit how deep frost can develop in the soil. Sent from my SM-G965U using Tapatalk

The ORD total from yesterday is probably off by 0.2 to 0.4 based off analysis of all nearby CoCoRaHS sites. Sent from my SM-G965U using Tapatalk

While trends have been unfavorable for the Chicago metro overall for the Monday into Tuesday period, not going to write off a better outcome here when this is still 84 hours out and beyond. It seems that the PV lobe location is going to be a big player and if that can slip east northeast a bit quicker, would imagine a more expansive precip shield to the northwest. It looks like even based off 12z operational runs we have a decent shot to get clipped with enough synoptic forcing to allow for good lake effect/enhancement (with already discussed favorable parameters) that could penetrate decently far west and southwest into the metro and support at least a couple inches if not more, especially lakeside. The GEMs have put their eggs into the Sunday night-Monday period, which the outer ranges of NAM supports, and the other guidance doesn't, so I'm not sure what to make of that yet.

I have to acknowledge I was too optimistic/aggressive on first real post I made to this thread. What we've seen is an adjustment to what probably was always a more realistic outcome in this setup, to have broadbrushed lighter totals and then a more focused corridor where mesoscale banding could enhance things. The 12z runs thus far show that nicely, 2-4" in that swath which should cut across roughly the I-80 to 88 corridors, and can't rule out 4-5" totals if the banding is stronger and more prolonged than expected given likelihood of >20:1 SLRs. Finally, Sunday night into Monday is trending up, especially on 12z RGEM, which has a broad 4-6" across the CWA. Sent from my SM-G965U using Tapatalk

Pivotal has a 20% off sale going [emoji2] The DGZ is extremely impressive on both the UKMET and ECMWF from their 12z runs. Sent from my SM-G965U using Tapatalk

Think the heavier bursts are enhancement of the LES due to aircraft seeding. Sent from my SM-G965U using Tapatalk

Best climo Sent from my SM-G965U using Tapatalk

I'm trying not to get overly caught in verbatim model run QPF/snow output. It comes down to what the general setup features with respect to large scale and mesoscale lift (fgen, lapse rate assist etc), some of which was covered in our long term AFD section. Sometimes all it takes is the rough idea on footprint of the QPF and banding locations to have higher confidence that you can get a swath of overperforming ratios and totals along the lines of what happened Monday. What Friday PM-Saturday has going for it if the setup doesn't change too much is duration. So if similar ingredients come into play like what we had on Monday you could expect higher upside for totals regardless of the raw model outputs based off duration alone. I think part of the possible frustration with the weekend period is that we had several runs of the GFS with decent ensemble support offering up more widespread bigger event potential, while several posts were made outlining why that outcome was rather unlikely. Euro has had similar depiction on evolution for multiple model cycles in a row now, while varying in QPF/snow output and NAM at this point showing an idea on what totals could be like (in I think a narrower swath than shown) if it all works out.

It's way too early to be in the concerned phase but just as a matter of that run, the 12z GFS brings back nightmares of 2/24/16. Key takeaway is that it still has a nice storm and would be a good sign if the GEFS members have several good hits. From a sub-forum perspective, looks like a pretty high chance at this range for a widespread warning type event for portions of the sub.

We emailed the regional climate focal point who is in touch with the climate program developers, hopefully there's a fix soon. Sent from my SM-G965U using Tapatalk

For some reason, the new climate program added totals from 1/31 to the February F6 form. The amount is correct in table above but the listing below is where the program is erroneously adding in 1/31 amounts. Sent from my SM-G965U using Tapatalk

It had backed off from 12z run a bit. The mean was still respectable for 24 hour totals of 1-2+" at 10:1, implying a mean of 0.1 to 0.2" LE. Would expect if things pan out that ratios would be above to well above climo again. Sent from my SM-G965U using Tapatalk

I just noticed that today too and it almost screwed me up doing a phone interview with the Sun Times. Sent from my SM-G965U using Tapatalk

What I get for getting hyped lol. Still think it can come back to a fronto type setup shown on previous runs today. Never bought into the GFS phaser idea, which quickly went away at 12z. EPS is usually a good gauge on things, so we'll see if things can revert back to 12z look or trend down again from 18z. Sent from my SM-G965U using Tapatalk

Thursday could help and if north side band sets up far enough north tomorrow. Sent from my SM-G965U using Tapatalk

I'm hoping to be on the Long Term desk tomorrow. The more I look, the more I like Friday-Saturday. Reminds me of the fronto setups from NYE 2013 through Jan 5 2014. Somewhere in the CWA (north of 80 currently most favored) gonna start snowing Friday afternoon and not stop until Saturday evening. I'd be shocked if we don't need a headline for the period and think it's already greater than 50/50 part of the CWA will end up needing a warning. Blowing and drifting snow impacts later in the event could rival the night of Jan 5 2014 given the deep snowpack and very powdery top layers and surge of unmodified CAA with 850s crashing to low-mid -20s C.

12z GFS beginning the cave process finally over the weekend. Still looks like it'll snow but ceiling is probably advisory type amounts. The above being said in terms of backing off phased dog solution, 12z runs today remain snowy this weekend with similar clipper fronto to what we've been getting and support for work week potential.

We'll have chances beyond this weekend, so we could get to 8-12+ by nickels and dimes over a week and a half or by a larger event. I still say chances are elevated for another widespread warning event over the next few weeks. For this weekend, the 06z GEFS provided decent support for the operational while the EPS is having none of it with one or two out of 51 members showing anything in the realm of the GFS. Banking on a phase happening and timing it perfectly is always a shaky proposition, so I agree on GFS outcome being lower probability. The Euro still shows light-mod fluff rounds over the weekend and then a decent signal for an event next Tuesday-Wednesday on the operational and a majority of EPS members. To get the outcome we want for the weekend, need to start to see movement toward it on the other globals and their ensembles (starting with 06z EPS) and of course for the GFS/GEFS to hold the signal.

Recall March 2019 flooding from Nebraska to NW IL after that bombing low. Sent from my SM-G965U using Tapatalk

The NAMs look like a toss for Wednesday if the foreign guidance comes in farther north. 18z Euro had supported another 1-3" I-88 and south or thereabouts. Sent from my SM-G965U using Tapatalk

About 2.5" here measuring in the front of my house where I had shoveled out Saturday's snow. I'm assuming about 2" is from this evening with the band just north of my area this afternoon. Sent from my SM-G965U using Tapatalk

Puffballs here (southeast Naperville near DuPage/Will border) underneath the band, +SN but a nice gentle deep winter evening. Stacking nicely. Edit: photo of my backyard for reference, the snow (largest dendrites around dime size) is stacking vertically on that chairback, showing how it's ultra light high SLR fluff and also no wind to disturb it. Basically perfect conditions in this band to max out efficiency. 00Z DVN sounding has 13kft deep DGZ with lapse rates >7C/km above the 700 mb centered f-gen zone.

Call in your latest report to the office if you haven't yet, could always use additional reports from the city Sent from my SM-G965U using Tapatalk

^Didn't age well [emoji38] Sent from my SM-G965U using Tapatalk

Just called in your report to the office. Nice dendies here but only a dusting since we spent much of the night north of the band. The ultra high ratios you got might bode well for later. Sent from my SM-G965U using Tapatalk