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Not the NAM, but same idea here. Quick glance looks like NAM is in the same camp as RRFS with 850 low and wind.

Yep, something tells me this is a now cast event. I think the warm nose is overdone. If the euro is right with the freezing rain, this place shuts down for a week or more. That damn artic air ain’t playing

Sums it up in a nutshell, Some areas may end up under the dry slot. KEY MESSAGE 2 DESCRIPTION: Forecast is still on track for a significant winter storm Sunday and Monday across the forecast area. We`re entering the time range where we can start picking out smaller features that can make a difference in snow rates and totals for the event. The primary messaging stands firm: significant travel impacts can be expected Sunday afternoon/evening and persisting through at least Monday evening. Increasing winds through the period will easily blow and drift the fluffier snow character, challenging snow removal in open and unprotected stretches of roadway. One smaller scale feature to watch amid the larger system will be ocean effect enhancement along the southern ME coast and NH Seacoast. Given the very cold airmass preceding the storm, the relatively warmer waters will provide some low level instability harboring locally stronger lift. Onshore flow Sunday evening through much of the night would bring some snow enhancement along the I95 corridor in York and Rockingham Co. Flow becomes more parallel to the coast come Monday morning, reducing this added effect, but greater storm dynamics will still be in play. Mesoscale banding will be another feature to watch amid a very expansive precip shield through Monday. 850/700mb frontogenesis depicted in NAM/GFS runs is fairly progressive as it lifts through New England Sunday evening. While deterministic and not set in stone, this can provide good insight into how quickly a stronger band of snow could transit the region. The current timeline overlaps with ensemble guidance suggesting heavy snow rates of 1 to 2 inches per hour during the overnight hours. Finally, a factor that could hamper snow accumulations. Overall trend in the storm has been an earlier onset and slow northern crawl. Despite the abundant and anomalous moisture content with this system, the lifecycle of low pressure systems usually features a dry slot contingent on the low`s maturity. This northern crawl the past few days has brought this feature closer to the forecast area, nosing in from southern New England. This would bring a period of less efficient snowfall. Still early to factor this in effectively for the forecast, but an item to watch.

The initial event back in late November was possibly caused by an interaction between the record low Arctic Sea ice and the -QBO. https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025JD044403 one model, HadGEM3-GC31-MM, has a statistically significant equatorward shift in vortex latitude, deceleration of vortex winds, and increase in sudden stratospheric warmings. Its response is found to be highly state-dependent, significant only in the easterly phase of the quasi-biennial oscillation (QBO). Though we cannot comprehensively conclude why models simulate this range of responses, our analysis does highlight areas for consideration in future work to better constrain the stratospheric response to Arctic sea-ice loss. We explore the role of ensemble size, resolution and basic state, including zonal-mean winds in the polar and midlatitude stratosphere and upper troposphere, as well as the QBO.

Not saying I trust it. Just saying I'd take it lol

I still wouldn't trust it. Seems wonky since yesterday

Yeah we are all pretty sure you said that about the NAM like 5 times yesterday!

The NWS actually mentions both scenarios. In other words they have no idea lol Intense isentropic lift atop the cold dome combined with anomalously moist air (PWATs of about 1"...in ~the 90th percentile of daily climatology)...followed by strong/focused ascent along a frontal boundary Sunday afternoon/evening will result in impressive storm total liquid equivalent precip...with 2-3 inches forecast across the mountains of southwest NC, SC, and northeast GA, and generally 1.5-2" elsewhere. Strong warm advection aloft will establish a warm nose that will eventually (a) support a transition from sleet to freezing rain from SW=>NE and ( allow for the valleys of far southwest NC...which will only be weakly affected by CAD...to warm above freezing. The first main forecast challenge is timing the transition to freezing rain. Forecast soundings become quite warm (+5C or more) aloft rather quickly tonight, suggesting a quick transition to FZRA. However, the cold layer at the surface is cold and deep enough to perhaps allow for some refreezing of hydrometeors before they hit the surface. However, this is far from a given...and it lends modest confidence to our ice/sleet accum forecast going forward. Nevertheless, most of the precip is expected to fall as freezing rain such that much of the CWA is expected to see storm total ice accums of 0.5-0.75." An exception on the higher end (0.75-1.0" with locally higher amounts) is forecast along the Blue Ridge escarpment...where the greatest alignment of persistent cold air and higher liquid equivalent is forecast. These amounts are expected to extend across the foothills of SC into the Greenville metro area as well. Widespread downed trees/lines and power outages are expected to be most concentrated in this area. On the lower end, a gradual transition to rain is expected along the southern and western periphery of the CWA during Sunday afternoon due to the synoptic pattern quickly becoming unfavorable for maintenance of cold air damming. This will occur as the upper flow pattern becomes phased...with a long wave trough being carved out over the eastern Conus and an upper ridge quickly building off the East Coast, resulting in cessation of confluent flow and allowing the weakening parent high to move far north into Quebec and become detached from the inverted ridge CAD ridge. The wind field responding to a developing coastal low will provide an additional erosion mechanism. As such, ice totals across the SC Lakelands and vicinity are expected to be in the 0.25-0.5" range, while the valleys beneath the Smokies may struggle to reach 0.25." In summation: forecast ice totals could be too low by 0.1-0.25" if the transition from sleet->freezing rain occurs significantly earlier than currently anticipated. Forecast totals could be too high along and south of the I-85 corridor if CAD erosion is more aggressive than currently forecast. Finally, locally excessive rainfall will be possible across mountainous areas where the transition to rain occurs Sunday afternoon...with the strong frontal band (where an isolated elevated thunderstorm cannot be ruled out) likely providing the tipping point to some minor runoff issues developing late afternoon/evening. .

Morgan county has almost a 10 degree difference from NW -> SE:

Am I radar hallucinating already?! The band of snow developing off the Jackson KY radar pushing into VA looks legit.

-2.2 Sent from my SM-S166V using Tapatalk

I would sign right now for the 6z Ukie

What about the hrdps? Its not terribly different than the nam but seems thumpier

Wtf

Don't give me false hope like that Sent from my SM-S166V using Tapatalk

Baseline for later obs: Not much difference between East TN and CAD areas this AM

Euro snow depth as of 7am Monday. Mix or not, that's still a lot of snow remaining on the ground after the storm.

Its not any better with delmarva. There was outrage last year, people ain't seen nothing yet. Im betting bills are going to easily be over $1000 a month for many. Some days its so bad, its actually cheaper to go stay in a hotel than it is to heat your house.

US National Weather Service State College PA 24 JAN 2026 @ 6:45 AM EST: Arctic air has returned to the region and will set the stage for frozen precipitation to fall with the approaching storm.

Looks like some blowing and drifting in the cards Sunday Snow likely, mainly after 5pm. Mostly cloudy, with a high near 11. Wind chill values as low as -6. Calm wind. Chance of precipitation is 60%. New snow accumulation of less than one inch possible. Sunday Night Snow. The snow could be heavy at times. Low around 4. Wind chill values as low as -8. Light northeast wind increasing to 5 to 10 mph in the evening. Winds could gust as high as 20 mph. Chance of precipitation is 100%. New snow accumulation of 9 to 13 inches possible. Monday Snow. High near 15. North wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 100%. New snow accumulation of 3 to 7 inches possible.

HRRR really showing very specific areas of downsloping in NE TN this afternoon:

1 for the low at Pen Mar Park, up to 2 now.

Sleet and ZR mix here. 28 degrees.

Current temp is 26 degrees.

The GFS 6z just for completeness although we are obviously in the mesos/short term ranges.