RCNYILWX

Even though it was warmer than normal, January 2012 happened to be the best month of that winter, two decent storms and the only AN snow month of the cool season. The second event in January 2012 had nice high ratio fluff with the longest duration of 1/4 mile visibility in snow at ORD and MDW since GHD I and caused nightmare travel on a Friday afternoon commute. Sent from my SM-G965U using Tapatalk

Not at the office so I'm not sure what went on with that. Seems like there's another chance to get on the board tonight if any of the occasional more robust snow showers move over ORD. This holiday mood dust is better than nothing. Did a lights tour around Naperville and the snow falling made for a nice vibe. Sent from my SM-G965U using Tapatalk

Both winter 2009-10 and 2010-11 had deeply -NAOs, 09-10 pretty much wire to wire, and were good winters for Chicago. The blocking in 2011 eroded in time for GHD I. That's not a statement about how things may go here the next few weeks, but just a note to point out a -NAO can be good here. With respect to moving forward, the ensembles also show a +EPO look with the big NAO block (backed up by the forecast teleconnection indices), so that could help prevent it from being more torchy and *maybe* assist in keeping some systems farther south. The deep blocking may come too late to help us next week though.

Certainly could, as the passage of the vort will be accompanied by a reinforcing surge of cold advection. At least according to the NAM depiction, with the lake effect + synoptic enhancement could see squally type stuff swing out your way during the day on Friday. Sent from my SM-G965U using Tapatalk

I had noticed the 12z RGEM brought in some light (around 1") accums to parts of northern IL late Thursday night into Friday morning. The models have been very consistent in a strong 700 mb vort wrapping around the stacked upper low, but main question has appeared to be available moisture. Tonight's 00z NAM showing some light QPF with this feature, so things might be trending toward getting a DAB+ down for Christmas morning. Sent from my SM-G965U using Tapatalk

Glass half empty view... It just doesn't want to snow here and we're a lock for BN snowfall. This week is very frustrating. Aside from a few model runs that drew everyone in, was never really that excited about big snow for the Christmas Eve threat, just as something thread the needle that could work out if everything came together right. Figured that we could meh our way to an inch or two but that's seemingly impossible now. Even the clipper warm advection wing this morning was a total fail. Glass half full view... Still have plenty of time left and that example of 1998-99 and a few other examples on Hoosier's list. 2012-13 was an interesting one too, because we had several near misses that winter that could've resulted in a much different outcome. The northern tier counties actually ended up rallying for a well AN snowfall winter. Another example not on Hoosier's list: 2014-15. November was cold and had some snow but only a T in December, tied with 2 other winters for least snowy December. Seemed like getting to AN that year was less likely but of course GHD II happened. Ya never know. Sent from my SM-G965U using Tapatalk

IDK, I'm not trying to be overly optimistic, but I don't think the most recent Euro weeklies and GEFS extended (I don't really look at the CFS and it's probably getting discontinued anyway at some point) look terrible for January. It appears the EPO will average positive but it doesn't look to be due to a black hole over Alaska but northeastern Pacific and northwestern North America troughing that's pretty common in La Nina's. The -NAO signal is still there to mute heights some in the east. If there's enough dateline ridging (-WPO) and a huge vortex doesn't set up over AK, that typically provides good cold air discharge that can bleed from western and central Canada into the northern Plains and northern Lakes. I see there being opportunities and probably averaging near to above normal temps but potential for some decent cold shots assuming cold does build into the Plains. Don't get me wrong, it's not screaming great pattern or anything, but it looks more serviceable than the dumpster fire that has been December, except for a few lucky spots.

Those coarse resolution CFS maps don't make any sense. Even if you account for background climate signals, there's no mid and upper pattern configuration that would torch the entire continent. If Alaska is torching that extreme, then there's gonna be a trough over at least the eastern half of North America. If a good chunk of the CONUS is torching, Alaska will be cold due to ++EPO from the TPV parking nearby, like in 2011-12.

Need this post on the potential event thread. Sent from my SM-G965U using Tapatalk

Added more stronger SLP members farther south than 18z EPS so roughly 2 clusters within that increasingly large spread. The northern cluster is still favored slightly more, probably tied to the key question of the northern stream short-wave. Due to the difficulty of getting a proper phase like depicted on the 00z Euro and some of the EPS members, think it's a lower probability outcome but still worth tracking because it's all we got. Sent from my SM-G965U using Tapatalk

It remains a thread the needle setup. It's the old need a phase to work out sort of deal, which as we all know went great last winter. That said, the last two runs have had important changes toward increasing potential for a solid event. Most importantly, the northern stream wave is slower and not as strong, which allows the southern stream wave to come up and eventually phase in. 00z EPS is rolling out, so we'll see shortly how much ensemble member support the operational has. Sent from my SM-G965U using Tapatalk

Euro showing the setup we need for Wednesday night into Thursday to work out. Long way to go but nice to see it on this run. Sent from my SM-G965U using Tapatalk

The IT side of the agency is a running joke. We always talk about what we should have but don't. When we got AWIPS2 5 years ago or whatever it was, it was okay for 2010. Anyone seen the Sportsmax skit from SNL? 'I have 500 sworn affidavits that our IT is the best in the world!' lol Sent from my SM-G965U using Tapatalk

The NWS way. And they didn't even put correlation coefficient on there, only the most useful dual pol product. Can't wait until the next new page comes out in 15 years. Sent from my SM-G965U using Tapatalk

Just one run but the 00z GFS is interesting for December 23rd. Shades of January 29, 2008 with a sharp Arctic front and rain to 1-3" of snow, wind, and a flash freeze. Would sign up for that. Sent from my SM-G965U using Tapatalk

Chicago hasn't had a 6"+ calendar day snowfall since 2/9/18. The last 6"+ snowstorm was 11/26-27/18. Was thinking about that in context of how NYC didn't get as much as some of the earlier model progs, but Central Park still got 10.5", which was their largest December storm since Boxing Day 2010. The last double digit snowfall at ORD was 11/20-21/15 and the last double digit snowfall during met winter was GHD II. Obviously major events are a lot less common out here than the east coast but we're seriously overdue. December has become a feast or famine month locally, mostly famine since 2010, with only 2010, 2013, and 2016 featuring above normal snow. The prior decade on the other hand had some very big Decembers (with also a few lean years), none more so than 2000. We won't be able to finalize what the December normal will be for the '90-'20 climate normal period until this month ends but prelim data is the December average/normal will drop to 7.5" from 8.2".

How was 95-96 in SE MI? That's the only recent low snowfall Nina that was colder than normal here. Even though Nina's don't have the reputation of big east coast winters, 95-96 is snowiest all time for NYC and 10-11 was on track to threaten that had it not stopped snowing in February. The ensembles continue with a not terrible look to close out 2020. Not cold, but not a blowtorch, and near average heading into the coldest time of the winter isn't a bad thing for snow prospects. Sent from my SM-G965U using Tapatalk

It's not the big storm we all want, but the Euro showing a decent Pac hybrid clipper on the 22nd into the 23rd and then a follow up weaker wave into the morning of the 24th not far from here keeps some hope alive of getting snow cover down for Christmas. The ensembles also have a decent look toward the end of the run with a -EPO, -PNA, -NAO, -AO. May make for an active and not too mild stretch into January if that comes to fruition. Sent from my SM-G965U using Tapatalk

Not gonna pretend that I'm optimistic for next week. It looks as usual too progressive on the operational modeling in that timeframe. The trend on the EPS last 2 runs to become much more northern stream dominant, which was the more likely outcome anyway, really diminishes the chances for anything to work out for us out here. All I can say is that it's far enough out for changes to occur from the current look. The cold looks like it'll be legit not very modified Arctic air, so all we can do at this point is hope that somehow we can get some snow down for what looks like it could be a very cold Christmas period. CAD for Christmas would certainly be a nice cherry on top of 2020 lol.

Plot twist, Alek's backyard as the snow capital of the Chicago metro. Edit: In all seriousness though, the LES parameters aren't terrible tomorrow from a thermodynamics perspective and duration as well. When I looked yesterday, lake induced ELs were peaking on the forecast soundings at 6k-7k feet, which is a bit better than marginal. The problem is the possibility as partial ice loss as we lose saturation in a portion of the DGZ. Overall DGZ saturation won't be great and lift peaks below it, so flake size should be pixies. Hoping the FZDZ monster is avoided.

Thanks for posting those, never got around to it yesterday. 12z run today looks better than yesterday anyway. Sent from my SM-G965U using Tapatalk

Yep it's thread the needle but since literally the only threat in the extended, gonna stay interested. Also, a white Christmas would be a bonus with how depressing it is around here otherwise in December, especially this year. 12z EPS looks a bit better than previous 12z and 00z runs and starting to see an uptick in 24 probs of accumulating snow, owing to increased member support. The GEM and GFS in that timeframe show how we can easily get hosed if northern stream is dominant and too progressive. It's safer to bet that the pieces won't come together. On a positive closing note for the possible setup, the antecedent air mass will probably be bad like this weekend, but the incoming air mass looks to be legitimately cold. Sent from my SM-G965U using Tapatalk

Having experienced some of the greats in the east (1993 Superstorm, Blizzard of 1996, late February 2010 Snowicane to name a few) and GHD I, hands down GHD I was the most intense non mountain winter storm I've witnessed. Since living out here, I've missed the more recent east coast big dogs, but don't think any have surpassed GHD I for a widespread area in terms of wind and snow combo. The most comparable widespread intense wind/snow combo on the east coast to GHD I in recent history was in the same winter as that one, the December 26, 2010 "Boxing Day Snowstorm". Was legit paralyzing for the NYC area. Sent from my SM-G965U using Tapatalk

Euro ensemble still with a reasonably solid look around that time and even some individual member support. Risk there is the ridging out ahead, and any system favoring far north/northwest sub. However, the smoothed out ensemble mean isn't going to do a good job picking up the influence of the -NAO and its tendency to limit how far north/west systems can track. This is despite the ensemble mean showing a strong signal of a -NAO and the teleconnection chart from the 12z run backing that up. @Hoosier are we allowed to post images from WeatherBell on here? I could post some visuals to illustrate better if I can. Sent from my SM-G965U using Tapatalk

In grasping at straws mode, but just looked at the 12z EPS, and heading into Christmas Eve and Day it does have a pretty interesting look, with a frigid cold trough dumping into the Plains and ridging out ahead into the east though still with a -NAO signal. Surface pressure anomaly even hints at a surface trough over the southern Plains lifting into the lakes and an expansive high over the northern and central Plains. A few of the individual members as expected from the above hint at some potential in the region during that timeframe. 00z run wasn't too different so we'll see if any continuity develops in that timeframe. Also GEFS not crazy far off but not as potentially interesting as the EPS. While we could do a lot worse than that modeled pattern, need to get it within 10 days. The hope is that *if* a system does develop in that timeframe, the -NAO could help prevent warm cutter. Sent from my SM-G965U using Tapatalk