Breakdown of Wednesday/Thursday hazards, what makes a blizzard, and updated NWS projected totals

Blizzard Warnings have not yet been issued, but I'm 99% confident that they will be. It's already beginning to snow here in Pigeon, and we already have about 1/10th to ¼ inch accumulations. The temperature is 32°, meaning that this snow is particularly wet and heavy, just as the Winter Storm Warning states. By the time it's all said and done, a very widespread region is looking at a foot, just as I expected it would be as of yesterday. Two days ago, the pressure center was pushing 970mb and it looked like we could get two feet. We still could get significant lake enhancement that pushes us close to those totals. For now, though, for certain, we're looking at a major blizzard which will drop a foot of snow.

So you may be asking: what's the difference between a Winter Storm Warning and a Blizzard Warning? Why hasn't the weather service issued one yet? It's going to be a blizzard, right?

It's all about current/projected conditions, and confidence in them.

Currently, with temperatures at 32°, the snow is going to be wet and heavy. This will change as the day progresses, and temperatures drop. 28° is the sweet spot for blizzards. That's when the snow is both fluffy enough to blow around yet still heavy enough to make moving it difficult. It's also when the atmosphere tends to be "primed" - most major storms really start to ramp up at that point. When the temperatures drop off this afternoon and evening, the snow is still going to be coming down at rates of 1½ to 2 inches per hour in some areas, and the winds are still going to be going at 35mph and higher. That's when I believe the Blizzard Warnings are going to start to be handed out.

The winds are already strong enough on the lake/around the lakeshore areas to qualify blizzard conditions once the snow really starts to come down and begin to blow around. The winds aren't going to die down. These conditions will continue for the next 24 hours.

NOAA defines a blizzard as an event in which 35mph winds generate blowing snow that causes visibility to drop to less than ¼ mile for 3 hours or more. That's the official criteria, and it can't happen when the snow is too heavy to blow around - hence no Blizzard Warnings for now. Winter Storm Warnings tend to coincide with Blizzard Warnings as any time snowfall rates/projected 24 hour totals reach a certain threshold (determined by the regional office), they're issued, but you don't have to have those significant snowfall rates/projected totals in order for a Blizzard Warning to be issued. If there's enough loose snow on the ground, for instance, and winds whip up to 40mph to cause whiteout conditions for a long period of time, a Blizzard Warning can be issued. I tend to start referring to strong winter storms as blizzards when they're powerful enough that it looks like they'll generate winds greater than 35mph for a long period of time, and that Blizzard Warnings could be issued or blizzard conditions could exist. I do this because I think the word "blizzard" carries a bit more weight and people start to take the storm a bit more seriously. When a blizzard is occurring, you do NOT want to be on the roads. Road closures due to heavy snow drifting, whiteouts that prevent you from seeing where you're going, and becoming stranded are all very likely when blizzard conditions occur. Traveling for any reason other than emergencies and without a proper winter survival kit is ill advised.

The other hazard to watch for today is potential thundersnow.

As everyone knows, thunderstorms tend to bring strong winds and torrential downpours. In certain situations, they can occur during the winter, too, embedded in a powerful system like this one. The fact that the eastern half of lower Michigan is under a general thunder risk by the SPC means that thundersnow is likely. Any areas experiencing that can expect not only flashes of lightning (in and of itself a deadly hazard) and torrential snowfall rates (reaching 3 inches per hour), but very strong winds - 40 to even 50mph. That's enough to generate blizzard conditions all by itself, as even heavy snow will start to blow around in that kind of wind. These types of thunderstorms tend to be clusters or linear rather than isolated, too, so these conditions can last a long time especially if the bands start to "train" (move sequentially over the same locations). If this occurs, expect localized areas with up to two feet of snow.

In this case, any Blizzard Warnings issued today will coincide with the Winter Storm Warning, meaning that you'll have blizzard conditions in a storm that's expected to drop a foot of snow. The combination of the two makes for a deadly situation for travelers. This doesn't look like a situation where you're going to be stuck in your house for a week, though, so don't allow the circumstances to be overhyped.

The weather across the eastern portion of the country today is very hazardous all around. Strong tornadoes could touch down in the Carolinas, and a tornado/damaging wind risk exists all the way from central Florida all the way to New York. This indicates a very powerful storm system, so Michigan is in for a rough ride, but we've been through this before, and we're likely to go through it again. As long as you stay off the roads today, and give the emergency crews their space, you should be in good shape. The key is not traveling needlessly in these types of situations. If you HAVE to go somewhere, make adequate preparations and make sure plenty of people know exactly where you're going to be, including the route. The biggest hazard in these types of situations is lack of visibility, so if you do lose track of where you are, pull over and wait for the situation to subside.