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The 06z UK has the Baja energy hanging back a little more than 00z. It's one of the northern models currently. Only goes out to hr 66 at 06z

The phasing will mean you crush mid Atlantic on the east coast with mid levels but that whole long wave trough development is severely positively tilted in the east. It’s a spin up with limited latitude gain.

One thing these models aren’t doing a great job with is showing just how expansive the sleet is going to be. Someone in the right spot is going to 4-6” of sleet only during this event.

This is turning into something historical. May still shift one way or another. But somewhere in the southeast is going to be shut down for a week or more. The euro and gfs are crazy.

Defintely coming up. Looks really good. Eps is also slightly further north

Overnight WPC probabilities: Pertinent parts of the overnight WPC disco: Model guidance generally remains in good agreement with the large scale pattern. All model guidance shows arctic air making it down to the Gulf and East Coasts, which will clash with southern stream energy to produce a high impact winter storm across the southern tier. However, some model differences still exist with the details of both the southern and northern stream energy. These details will impact things such as the timing, snow/ice line, and the northern gradient of the snowfall. While these details will need to be worked out over the coming days, it seems almost certain that a significant winter storm will occur. The 12z/18z GFS runs from yesterday were extreme outliers with a much slower and even cutoff southern stream energy near CA. The 00z GFS has since come into better agreement with the other models, but given it appears to just be catching on to things, we still prefer to only give it a little weight in this forecast. Otherwise taking a blend of the ECMWF/CMC/UKMET, the ECENS/GEFS and the AI model suite, seemingly results in a pretty good middle ground forecast at this point and is reflected in the WPC QPF forecast. On the southern side of this system significant freezing rain is expected, likely resulting in dangerous travel conditions and power outages. Given the arctic airmass in place, temperatures will likely only be in the teens and 20s where freezing rain is occurring, which will only act to increase travel impacts. The exact swath of ice will a bit uncertain until we get closer to the event...but currently the highest probabilities stretch from portions of central TX into the lower MS Valley and into portions of SC/NC. To the north of this icing threat will be a swath of significant snowfall stretching from OK into the TN Valley and Mid-Atlantic. Again, we will need to fine tune the northern and southern gradients of this snow, and also the exact magnitudes...but a rather wide swath of significant snowfall is likely. Temperatures in the teens and 20s will increase travel impacts from this snow and also result in snow ratios likely higher than climatology. This should result in higher snowfall totals than applying a simple 10-1 ratio to QPF would give you...especially on the northern half of the snowfall axis.

To me. It looks like the GFS and AIGFS is still keeping it suppressed. Anything we should we be concerned about?

Bank on a little bit of everything at this point.

4 this morning.

Morning discussion from LWX KEY MESSAGE 2...Near-record cold this weekend, along with increasing potential for a significant winter storm. As mentioned above, a potent cold front pushes through the region late Thursday into Friday, followed by a reinforcing Arctic front late Friday into Saturday. This will lead to increasingly cold conditions each day from Thursday through the weekend. Well below average temperatures are forecast, especially by Sunday. In addition, some upslope snow showers are possible over the Alleghenies, with low but non-zero chances of light precipitation further east on Friday. Extremely cold temperatures are becoming likely Saturday night into next week, with lows in the single digits and wind chills at or below zero. Near-record low temperatures are possible during this time. The upper-level pattern becomes quite active in both the northern and southern branches of the jet stream heading into this weekend. Models continue to be in generally good agreement regarding the development of a low pressure system that tracks across the southern U.S. A broad area of baroclinic/frontogenetic forcing will develop along the interaction of an Arctic high to the north and the deepening low. Ensemble guidance continues to show an amplified southern stream influence - something we have seen very little of so far this winter (typical of La Nina). The surface low may not escape so easily out to sea given the negative NAO block. The nearby steady source of very cold air and the amplified southern stream occurring in tandem are what raise some red flags for significant wintry precipitation potential this weekend. Ample cold air will remain aloft and at the surface with strong high pressure to the north and the strong baroclinic zone to the south. As a result, the 01Z NBM 48-hour probability for at least 6 inches of snow (ending 12Z Mon Jan 26) are at 40-70pct from NW to SE, and around 20-45pct for 1 foot of snow from NW to SE. There are some noteworthy probabilities for even higher amounts, as well, but uncertainty still remains in regards to the exact track of the system which could lead to a sharp QPF gradient on the north/northwest side of the system possibly somewhere over our area. The latest numerical model guidance continues to show consistency in regards to the potential of this significant weekend winter storm across the area. Trends for precipitation onset time favor Saturday (most likely in the afternoon), with the heaviest precipitation over the area then occurring through Sunday afternoon. The last four runs of the ECMWF-AIFS (deterministic) have shown a southward tick to the axis of heaviest QPF, likely due in large part to a slower ejection of shortwave energy out of the Southwest CONUS causing a slightly flatter and more suppressed storm track. However, the 00Z operational ECMWF (deterministic) as well as several members of the EPS and EPS-AIFS (among a handful of members from other ensembling systems) are also slower and more amplified with a trailing northern stream wave dipping into the Rockies late in the weekend; these two slower/deeper waves then phase as they exit the Rockies and head for the Mississippi Valley. This scenario results in a broad, flat area of low pressure the gets caught underneath Arctic high pressure building over the Northeast CONUS Saturday night, and drifts over the baroclinic zone draped from the SW Atlantic into the Gulf. This low then eventually gets absorbed into the deeper phasing trough approaching from the west. This lifts the low pressure northward up the coast causing precipitation to linger into Monday. It should be noted that this is a relatively new shift, not yet reflected in 01Z NBM progs that were used as a baseline to the overnight forecast. Have not deviated from NBM and will instead wait to see if there is some consistency in this outcome, or if a more suppressed solution becomes more likely. Depending on where the frontal zone is and where the area of low pressure tracks, there could be significant wintry precipitation this weekend over a large part of the South to Mid-Atlantic CONUS. As noted, the potential is still there for that strong Arctic high pressure to suppress the low pressure system to our south. However, the strengthening upstream blocking pattern could essentially put a floor on how far south the low will track. Accumulating snow looks almost certain this weekend, with an increasing likelihood of a warning-level event for much of the region. But how exactly all of the moving pieces interact will determine the difference between a moderately impactful snowfall versus something much more significant. It is important to monitor this threat closely this week as the different parts of the system become better sampled by surface and upper air observations. Stay tuned to weather.gov/lwx/winter for the latest updates.

12/8F, chilly morning here

Thank you for all of the folks who stayed up and did the play by play! I just don’t have it in me anymore. I’d have to look but we seem to just keep up trending QPF for this event. Idk if I’ve seen anything like it in quite some time. 1.5-2” into temps ranging from the teens to 20s is going to be a sight.

It is hard to take those ZR maps seriously. I haven’t checked euro soundings but most of that ZR area is solidly IP and really not even close on GFS. There is an opportunity here given high QPF for areas to get greater than 6” of snow and 2-4” of IP which would be insane for longevity of the snowpack

We can't shovel potential and probability, only the real deal can be shoveled. but we'll take this at this point.

6z euro continues with the clean phasing.

Seems like it's trending more to a low to moderate overrunning Sunday to a higher end coastal potential Monday as the SW energy is trending to a phase

And I know we have the weekend to start. But checkout the GFS through the end of it's run. It could be rough sledding around. Pun intended. That's over 30 inches in many places.

Oh for sure, just something I noticed up here when comparing runs

Over a foot of snow with over 1/2” of freezing rain over a giant area would redefine the word “crippling” for years to come

They say good things come to those who wait, slightly slower evolution but the ceiling is very high in that scenario. Would be very PD2 ish in duration and potentially even magnitude.

If you look at the progression of the Euro, it brings the northern stream trough down with a delay that allows the Baja low to fully ejected and the 2 combined/phased are what we get with that 5H anomaly map I posted.

This looking more and more like a crusher for ACY, DC, Baltimore. There is a -NAO developing around the time this makes it to the east coast, so a slower track and more phasing are likely than currently modeled. That said I don’t think that portends a big latitude gain.

Pretty good trends overnight IMO. Seems like potential for a decent event Sunday/Monday. Don't think the upper end is too high here but could be a nice moderate kinda event?

That would create so much infrastructure issues well into the following week. I am sure that tems are well below zero over that snowpack as well

You thinking WNC sees a little bit of everything? Or chance it stays all snow?