ILSNOW

6z GEFS

Plumes for ORD up 6.76

NAM over running

As Chicago WX shared yesterday you can thumb thru the 50 different Euro members https://weather.us/model-charts/euro/illinois/m23_acc-total-precipitation/20220205-1200z.htmll

Get to enjoy GFS till Euro comes out.

ice

12z GEFS

What a cutoff on the NW side in IL. Lake county 8-12 and 20 miles west in McHenry 2-4

nice part 1 for central IL into IN and MI

6z NAM is better for the immediate Chicago area. 6z GFS not backing down nor is the 6z EURO. Who blinks first?

GFS ensembles

GFS is kinda on its own at the moment

so not looking good on 2nd wave ?

and ice

back to back 30+ for you when was the last time you had that?

Ricky Here`s a breakdown of 3 general clusters of outcomes, in which the 12z global operational models fit decently into: 1) Weaker and farther north Hudson Bay PV will allow for slightly more pronounced eastern height rises, which enables strong moisture surge Tuesday evening and night to reach farther north into the CWA for potentially significant snow accums into Wed eve. The short-wave out over the eastern Pacific is slower to eject and positively tilted and subsequent stronger synoptic system later Wednesday night into Thursday takes off too far south and east for meaningful additional snow (aside from any lake effect chances). Similar 12z model run: ECMWF 2) Weaker and farther north Hudson Bay PV, more pronounced downstream ridging allows for moderate to heavy overrunning snow. THEN southwest short-wave takes on neutral to negative tilt and ejects out to favorably develop a stronger system with ~1005 mb surface low tracking near or north of Ohio River. This progression would bring another round of moderate to heavy snow along with even stronger winds into or through Thursday, aided by impressive right entrance region jet dynamics. In most amplified ensemble members, could even be some wintry mix p-type issues in parts of the area. Similar 12z model run: GFS 3) Stronger and farther south Hudson Bay PV lobe results in confluence and slightly suppressed positive height anomalies, and the strong/drying influence of incoming Arctic high to have more influence. Result would be banded overrunning precip having a very sharp northern cut off and focus the heaviest precip and snow axis into our southern CWA and points south and east (or even south of CWA altogether in most northern stream dominant ensemble members). Similar 12z model run: Canadian. Suffice to say that all three of these outcomes remain plausible and represented by the distribution of ensemble members of the three parent models. Overall, there is *currently* a slight lean in the ensemble means toward roughly outcome 1, favoring our southeast half or third, occurring amidst brisk northerly winds. For this reason, the most recent WPC Day 5 accumulating snow/sleet outlook appears reasonable with southeast half having higher (50-70% probabilities) vs. northwest (30-50% probabilities). Since the three approximate clusters described above remain plausible outcomes, we continue to urge caution with any individual model run snowfall outputs being shared. Stay tuned for updates as the potential event draws closer when we can be more confident on some of these still uncertain details.

We will have to see what the former King has to say.

12z UKMET still south but coming north

slight difference between CMC and GFS @ 120hr especially with the placement of the high

12z GFS is a hoosier special

part of Ricky writeup A look at the 12z GEFS and ECMWF (EPS) ensemble mean and members certainly stands out for increasing confidence in a significant winter event for part of if not much of the CWA despite the rather extended lead time. 4-day (10:1) snowfall means up in 5-9" range, along with 30-40% probabilities of 6"+ totals and 60-90% probabilities of 3"+ totals highlights the high % of members with significant snow swaths. Can`t rule out the outlier members with everything shunted a bit south, though with that said, felt comfortable even slightly adjusting PoPs upward a bit from NBM initialization due to likely to categorical probabilities of measurable precip. Regarding the wintry mix threat, should a more amplified wave shunt elevated baroclinic zone back north a bit (such as on 12z operational GFS and several ensemble members), this would increase risk of a zone of freezing rain and sleet given northerly cold air drain. Added in slight chance wintry mix mention for areas south of US-24 Wednesday through Wednesday evening. Timing wise, looking at a late Tuesday night/Wednesday morning start, though there`s certainly wiggle room on this element 5 days out. Accumulating snow could potentially continue into or through Thursday per some of the slower solutions, ending as a window of favorable lake effect parameters Thursday night into Friday. If we do add to the already extensive snow pack, both Thursday night and Friday night could be exceptionally cold as the high pressure transits our area. Castro

HRRR has been moving steadily west and now north hammering northern cook