Long Duration Light Snow to Impact the State Thursday and Friday (2023)

​Good afternoon from SCW!

I’m on the clock today so this is going to have to be a quick discussion, but one thing that will not be quick is our upcoming snowstorm. While snowfall rates won’t be all that impressive, the duration of this event stands out – we’ll see snow break out tomorrow morning and continue all the way through Friday afternoon, with some models keeping snow around into the overnight hours. Steady light to moderate snow is expected for most of the period, with the potential for some intermittent breaks on Friday, and all together will add up to a moderate impact event for the state. Let’s dive into the forecast.

Overall Evolution

Here’s a look at the evolution of the system on the GFS. This is one of the longer duration solutions, with snow breaking out by 7 AM tomorrow and lasting all the way into the evening hours of Friday.

​As a frontal boundary moves into the region, several waves of energy move over the boundary and bring precipitation to the region. While none of them appear especially large, there will be enough moisture along the gradient to maintain fairly consistent snow for the state. The best chances for some heavier snow rates come at the beginning and end of the system; the initial wave at the beginning appears a bit stronger than others, and some models suggest we could see some deepening of the low as the main system finally hits the ocean on Friday. That could result in some bands of heavier snow developing, and any areas that see those bands would be favored for the highest totals.

As the system has ticked south a little bit since yesterday, it has also cooled off a bit, and the guidance consensus now is for all snow across most of the state. There is some risk of mixing along the shoreline, especially in eastern areas, but at this time, I’m still leaning towards an all snow forecast.

Models are in pretty good agreement on total precipitation amounts, with generally around a half of an inch of liquid (or maybe a bit more in some spots) across the state. The outlier was the NAM, which was showing a stronger and more amplified system which would bring over an inch of liquid to most of the state, however, it’s started to back off in the more recent runs and move towards the guidance

While I’m not totally discounting the possibility of that solution returning it, I’m very skeptical of it, and so for this forecast, I stuck pretty close to the guidance consensus. There’s some risk that we will see lower amounts if the south trend continues, but there’s enough wiggle room with the precipitation shield that I think several inches for all is a near certainty.

Summing it all up, I’m expecting three to seven inches of snow for most of the state with most areas falling in the four to six inch range. Any areas that see heavier banding will be towards the higher end of the range. I wouldn’t be surprised to see some 8-10” numbers in areas where heavier banding occurs (maybe interior southern areas and the southwest coastline?) but I don’t think that will be widespread enough to warrant a higher range.

Storm Details and Impacts

Here’s our forecast map and our thoughts on the impacts and the elements on our grading scale.

Snow Accumulations

I’m going for a widespread 3-7” of snow, with a chance for up to 10” in areas where the best banding is in place. I think the greatest bust potential is in far northern areas of the state if the storm continues to shift south, and I thought about splitting the state into two zones with the heavier totals in southern areas, but for now, I’m going to stick with the widespread 3-7” for two reasons – ratios will be a bit higher in northern areas and it doesn’t take very much banding for an area to get closer to the higher end of the range, and it’s hard to know exactly where that will be.


Models have moved the start time earlier, and now project snow to break out as early as the start of the morning commute tomorrow. The end time is a bit trickier – some modeling tries to wrap things up by mid-morning Friday, though the bulk of the guidance continues snow into the afternoon and even into Friday evening on some models, driven by some coastal enhancement as the low tries to exit. I’ll split the difference and expect a snowy morning commute Friday but some improvement by the evening.

Here’s a look at the GFS and RGEM for 7 PM Friday evening – the RGEM has snow long gone from the state, while it’s still going on the GFS for most of the state (and will for several more hours). Notice that the system is much more consolidated and further west on the GFS.

Winds/Power Outages

Good news is that I don’t expect any notable winds with this storm and power outages should be isolated or non-existent.

Road Conditions

Generally light snow rates should allow road crews to keep on top of the primary roads but expect slow going on secondary and tertiary roads where plowing is less frequent. Any period of heavier snow could quickly accumulate and cause slower travel even on the main roads. That said, you likely won’t be going the speed limit for most of tomorrow and most of Friday, so take it easy and leave plenty of time for your travels.

School and Business Closings

This is a tricky call. The amounts aren’t huge, but the timing isn’t great. I would expect issues with busses both tomorrow afternoon and Friday morning, and so I’d expect fairly widespread closings of in-person facilities tomorrow, with Friday being a trickier call depending on when the storm ultimately moves out and if there’s a break in the snow for the crews to get the roads cleaned up overnight Thursday. If there wasn’t a remote option, I’d expect some districts to go for it to avoid losing two days to a borderline event, but given the availability of the remote option, I would suspect most if not all districts will choose that path for Thursday and Friday. That said, we at SCW are full supporters of the traditional snow day and urge all decision makers to give students the childhood memories of a school and screen free snow day with plenty of snowmen, snowballs, and hot chocolate (and some shoveling assistance too!). I’d expect most businesses will remain open with some potential delays Thursday/Friday depending on the commutes.

Overall Impact

While ~5-6” of snow can be a high impact event depending on the timing, it’s spread out enough here that I think most areas will be able to stay on top of it, and so I’m expecting a moderate impact event for the state. In order to see higher impact, we’d need to see a solution like the previous NAM runs verify, and as much as I’d love a foot of snow right now, I just don’t buy it.

We’ll update tomorrow morning with any final changes to the forecast and as needed throughout the event. Stay in touch with us on our social media pages to ask questions and share your observations – we rely on and appreciate them. Thanks for reading SCW and enjoy the snow!


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