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Blog: A multi-layered mess of rain, flooding, wind, and some snow. (Updated)

Sigh! Isn’t today the day that I’m supposed to come back from my break and talk about the nice time I had while I was off? Well, the weather has me doing otherwise. It is a mess out there, and it is going to stay a mess through the day!

Here is the setup: Today we have an area of low pressure moving northeast along a stationary front.


Satrad

This will roll through our region through the morning into the afternoon. It is much colder north of the front and much warmer to the south.

Temps This Morning

With the warm air, thick moisture, and some spin, there is a threat for thunderstorms and isolated tornadoes over parts of North Carolina until about 11 a.m. (Update…the threat for severe weather is gone for the afternoon.)

Tornado Watch

There is also a large amount of wind shear overhead. This isn’t impacting most of the area because it’s just too cool and stable. However, there were pockets of heavy downpours moving onto the Southside.

Radar This Morning

Through time today the cold air will wrap in on the back side of the low. This will allow for a changeover to a wintry mix and then some snow. The timing of this is tricky. Here is what two of our hi-res models show for noon:

HRRR Model (Midday)
Future Trak (Midday)

So if we blend the models, then it looks like there will be a mix changing over to some snow northwest of the metro, but it will be rain with some mix in the metro during that time. Notice the temps will be falling, but they will be mainly above freezing.

Between noon and 3 p.m. the rain-snow line creeps southeast. This means that there will be a mix with some snow in the metro with some accumulating snow north and northwest of the metro.

HRRR Model (3pm)
Future Trak (3pm)

I tend to favor the HRRR as it is probably handling the temps by the water better.

This should wrap up as a few flurries this evening. Then we’ll dry out. Here is what makes this wintry forecast so tricky:

  1. Surface temps will be above freezing for most of the time. The sun isn’t going to be out to warm things up. However, the strong north winds will drive down that colder air. it will just take some time.
  2. That same strong northeast/north wind will be coming in off of the Bay (and ocean for some spots). The water temps are near 50 degrees. So that will likely create more of a mix zone than just purely snow. That is likely for Virginia Beach, northern Norfolk, northern Portsmouth, Poquoson, and Hampton.
  3. The ground is very wet. It takes much more energy to cool standing water. So it will take a while for the surface to be cold enough for snow to stick anyway.

So that is just a taste of what we are dealing with. Having said all of that… The models are showing some light amounts in Hampton Roads. They are all showing higher amounts to the north and northwest.

Snowfall Forecast (Future Trak)

Putting these together and factoring in the above features here is my snow/precipitation forecast:

I updated the map around noon to drag the 2-4″ zone southward.

Again, there is an emphasis on the (Grass and Decks) part. It’s possible that the accumulation will happen briefly and then melt from underneath. Roads should take longer to cool. So most of them should be ok. The exception is where the Winter Storm Warnings are issued. The bottom line is that the snow shouldn’t be a big issue in Hampton Roads, but it could cause some travel problems to the north/northwest.

One other big issue is flooding and tidal flooding. The tide is up between 8 and 11am.

Tide Forecast (Sewell’s Point)

This is going to be some minor to moderate tidal flooding in Hampton Roads. Here are some other locations:

Tide Forecast

Tidal flooding can cause problems by itself, but over the past few years, we’ve really had to be aware of tidal flooding causing poor drainage. So that will be the case until a little before noon. We’ve had about 1-2″ of rainfall so far. We’ll see another half inch up to an inch before the changeover.

Winds will be strong all day. We already had a few gusts to around 40mph. There will be some more through the day.

Wind Gust Forecast

There have also already been some power outages in the area. There could easily be some more until this evening.

If the wind changes sooner or later from northeast to north, then that could change the timing of the change over to a mix and then snow.

Tonight skies will clear, and temps will drop. We’ll get down to the upper 20s to low 30s. This will lead to some patches of black ice and ice. let alone we’ll see how much snow is on the ground north of the metro. Ay yay yay!!!

OK…After all that the weather will be much quieter for the rest of the week. Chilly and dry tomorrow…Cool and dry on Wednesday. Stay tuned for more updates!

Meteorologist: Jeremy Wheeler