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Snow blog: From cold rain, to a mix, to snow showers (updated)

Update…The models have updated. Our RPM/Future Trak model has finally come up in totals. (That’s good!) The NAM has dropped a little more, and the National Weather Service Blended model (I believe) has come up a bit. Here is a snapshot of the latest models.

Updated 4 Forecast Models

Previous Discussion:


We are still looking at a high chance for snow showers in the region, but it will be a developing process. It won’t all come in right away. We’ll start with some cold rain showers this afternoon. Then a wintry mix for a time later this evening. Then it will change over to snow showers tonight. The models have almost all trended down since last night. Here’s a quick glance at the snow forecasts from the models that I’m seeing this morning:

4 Computer Model Snow Forecasts

The big development was that the NAM model had drastically come down. Now it is closer to the other models. Our model updated around 6:30am this morning. As I write this it is hardly showing any snow for Hampton Roads now. I still think the forecast will be somewhere in the middle.

The setup for today is that we have a big area of high pressure over the northern U.S. An area of low pressure is forming over the Gulf coast. It is moving east along a stationary front.

Regional Weather Map

Moisture is pushing well north of the low, and it will continue to do so as the low slides east today. We’ll have a lot of clouds through the day. Temperatures will rise to the mid 40s. Maybe some low 40s inland/north. This is just a bit milder than yesterday’s forecast. It’s a difference of a couple degrees, but that could make a difference this evening. We’ll have some scattered rain showers move up from the south by this afternoon. Here is what our Future Trak model shows:

Future Trak (This Afternoon)

The models all agree now that there will be a wintry mix forming during the evening. Some models like the NAM have it forming by 5-7pm. Our model has pushed back the timing a little to 6-9pm.

Future Trak (This Evening)

The evening commute will be messy whether there’s wet roads or wet with a melting mix. Either way the mix will melt at first. I think that is a key part of the forecast. Surface temperatures are forecast to be in the mid 40s during the day. They will gradually drop through the evening unless the precip comes down very heavy. I don’t expect that to happen at this time. However, they will probably stay above freezing for most of the evening and possibly until even after midnight. However, it will be cold enough (aloft) for the mix to change to snow. It still looks like a band of snow showers will develop overnight. It does look like it will be mainly a mix for the Outer Banks.

Future Trak (Tonight)

The models are in decent agreement about the end time. There’s a little wiggle room, but our model wraps things up between about 1-3am for Hampton Roads and 4-7am for the Outer Banks.

The GFS keeps the precip going a bit longer. All the models have us dry, cold, and windy on Friday. Temps will bottom out near 30 or in the low 30s in the morning AFTER most of the precip has fallen. They only have our high temps in the upper 30s on Friday. Wind chills will be in the teens and 20s as winds gust out of the north to 30mph at times. We’ll be partly cloudy.

So here’s a little more on the models. They have basically been all over the place over the last few days. (is that a surprise?) A few days ago the European model had some snow in our region with all the other models dry. Then the Euro dried out a couple of days ago, and the other models started to go with snow. They started to increase totals yesterday. Especially the NAM model which was going off the charts. Since last night all of the models have come down. Here is that 4 panel graphic again that I showed at the top of the blog:

4 Forecast Models

Again…our model has the least amount as it is showing a longer time of a melting mix. It has been one of the driest models since it got within range. The NAM still has a decent amount of snow for the region, but it is much less than yesterday’s 5-10″. If anything the National Weather Service Model has increased a bit since last night (as of this writing). I still think that the water temperatures will also be a factor. Water temps are in the upper 40s right now. With a strong north/northeast wind that should promote a lot of melting near the ocean and near the bay. Will that be 1-2 miles from the shore or 5-10 miles. That will be up to how strong the wind is, and that is tough to call. It will be highly local.

With all of that said…here is my latest snow forecast. I’ve increased it since yesterday. However, I’m tempted to lower it based off the latest model trends:

Update: I tweaked the map a bit since this morning. I pushed the 2-4″ north just a bit, and the 1-2″ south just a bit. The 4″+ zone also moved northeast a touch.

Here is the closer view of that map:

Snow Forecast Closer View

I will say that on the satellite/radar it looks like there is plenty of moisture to our west and southwest. I do still think a snow-band will form from southwest to northeast tonight. It think that band will be heavy enough to overcome the warm ground. However, the recent trend of a longer mix time and the milder water temps could really limit amounts in some locations. Maybe we will develop some snow islands over the region where there are pockets of a couple of inches on the ground surrounded by areas of bare ground or a dusting. I do still think the highest amounts will be from the western Albemarle area up into Chesapeake and Suffolk near the state line.

One important logistic that I want to mention. School administrators should have some time to go out and assess the situation before they have to make the call to close or delay schools tomorrow morning. I suggest to wait until early tomorrow morning to make the call if you can.

As always…we’ll have more updates through the day. I will likely have a big update by WAVY News 10 Midday. I’ll likely do a FACEBOOK Live on our WAVY 10 page around 11am with a quick update. Stay tuned for updates.

Meteorologist: Jeremy Wheeler