Blizzard 2016 Thoughts

While it is still fresh, some thoughts on this storm.

1.) Give New Jersey the record it deserves. Being a native of New Jersey, I sincerely hope NWS investigates the 33″ Morris Plains and 35″ CoCoRaHS ob from Mine Hill. The 24 hour record for snow in Jersey was 32″ in 1915 in Rutherford. Based on the timing of snow obs at Morristown (MMU) and Somerville (SMQ), I suspect almost all this snow fell within a 24 hour period, and if the totals can be vetted and verified, a new state record should be established.

2.) Kudos to forecasters and communicators. While this was a challenging storm to pin down, I thought almost *all* forecasts for this event were incredibly well done. Everyone deserves credit. Unless you bought the NAM literally and took 1-2′ of snow to I-90 in Massachusetts, or unless you completely ruled out any chance of New York City seeing major snows, you did well in this event.

Between the uncertainty of the northern fringe gradient, the potential for epic snows around DC, the coastal flooding potential, there was a lot to communicate in this event. In my opinion, it was all done very effectively by so many within the weather community, from the NWS, TV, private sector, and social media types.

3.) It’s not the model, it’s how you use it. The amount of “modelology” surrounding this event was…annoying to say the least. So many people declaring the NAM victorious. At one point or another, most major global models indicated enough variability and risk on the northern fringe of the snow to include most of New Jersey and New York City within the “margin of error” so to speak. The NAM did not “win.” Again, judging by the map above, if you lived in Hartford or Springfield, MA or Boston and used the NAM, you had a lot of egg on your face. That’s not an inconsequential populous. Yes, the NAM was the more aggressive model in New York City and on that metric alone, it did well. But it didn’t win. No model “wins.” As a forecaster, it’s your job to objectively analyze the models…all of them…use every tool in your toolbox and make a call. If you blended the NAM with the RGEM and the Euro/GFS, well then you did *damn* good in this event with your snow forecast most likely. Likewise, if you outright dismissed the NAM because of last winter’s NYC debacle, you probably failed too. Recency bias will kill you. Many of us joked about the NAM being the NAM…and that is certainly exaggerated by some of us (including me…I do use the NAM daily when forecasting for Texas and Louisiana, and I have used it aggressively at times). It has a reputation for being sketchy, but I know most rational forecasters do use it and consider it.

We just can’t turn this into some training camp competition. If you use the NAM alone for the next event, I guarantee you your forecast will have serious shortcomings. Use all the tools; know their strengths and weaknesses in the areas you care about and leverage them to your advantage as a forecaster. And don’t fall prey to recency bias.

4.) Can we please figure out snow measurement? This is not a uniquely DC thing. It’s been a problem in New York City in the past. It’s a problem in Denver. It’s a problem in so many places.

Fully understanding weather and changes in climate in places is heavily dependent on having a long set of reliable actual measured data at those places. When we can’t depend on data being reliable, what use do we have for it? Why do we have a top 10 list of snowstorms? Why even bother? It’s time for someone to step in, standardize, and properly coordinate snow measurements at places. Cost isn’t an issue. The way I’d approach it: You know how many people would volunteer to do it correctly and love every second of it? Find a spot representative of a city (not an airport across from it and adjacent to a river), probably on state or federal property, and have a team of volunteers at the ready, able to coordinate, trained properly by NWS, and eager to jump in when snow is predicted. Adjust the site as needed for changes in population distribution, new construction, etc. We’re making this a lot more difficult than it needs to be.

5.) Storm names are fine, but we don’t need 30 of them. When they started, I was skeptical of The Weather Channel naming storms, though I believed from the beginning that it would be a successful venture. I think to this point, the storm name concept has worked. I get the frustration, but that ship has sailed and it’s not coming back. So we either do it right or we continue doing it this way, where there were at least 6-7 different storm name hashtags for the same storm. It’s a patchwork free-for-all, and it would be nice if we could streamline it. It would be better for everyone. The research argument is simple: How on earth can we find pictures and tweets from this event without searching through eleventy different hashtags? Instead of still griping about the fact that it’s done, come up with a way to do it better and get everyone to agree. It will be less difficult than anyone thinks, but to make it universal, it can only come from the NWS. It’s time.

Those are my thoughts. What are yours?

Follow me on Twitter: @mattlanza.

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Jonas 2016: ♫ People Are Blowing Snow ♫

If you haven’t thought of the Weezer song with regard to this storm, you’ve failed me. It deserves some parody. I tried. Oh well. Onward…

What’s changed since yesterday, Matt?

Not much. Other than bread and milk supplies in the grocery store being dwindled.

  • The storm is still coming.
  • It still appears the metro Washington, DC area is the bullseye for snow.
  • Coastal flooding is still a serious concern.
  • Blizzard Watches have been expanded to include much of Jersey, Philly, and the New York City area and Blizzard Warnings are posted for DC and Baltimore.
  • The northern edge of the storm is still going to drive most meteorologists to their local bar.

So how much snow for me?

Here’s my updated map:

012116_Snow_Forecast
My own personal snow forecast as of 5:30 PM ET Thursday. Again, not official, but my way of expressing it.

Again, I’ve highlighted the two key areas of uncertainty. The northern fringe is going to be a royal pain. There are some models that still bring good snow 8-12″ to NYC, but I don’t personally buy that scenario right now. Based on my experience, these sorts of storms have disappointed on the northern fringe, so I’d rather take a conservative stance there.

From Philly into Baltimore and DC, it gets complicated too. You’ll have a number of factors driving snow totals. I expect there to be issues with mixing in spots. Convection (thunderstorms…yes, thundersnow) will also be likely with this storm. In those cases, sometimes strong bands of snow setup over one place and effectively “rob” another of snowfall. So it’s possible that the final snow totals will not look this uniform. You could easily go from 18″ one place, to 10-12″ a couple towns over, back to 18″ a couple towns over from that. It’s chaotic. Snow forecasts aren’t meant to be simple.

What about the blizzard part?

Yes, Blizzard Watches and Warnings are posted all over. Fun fact: The amount of snow you see has 0 factor in whether or not a storm is defined as a blizzard. Why is that? My honest answer is because we like to make things difficult on ourselves as forecasters and communicators. That aside, it has to do with impacts mostly. A blizzard is supposed to mean wind, which limits how many storms meet the criteria of one…thus making it special and making it stand out.

For a storm to be a blizzard, it has to have 3 hours of winds sustained at or frequently gusting to 35 mph and visibility below 1/4 mile. That’s all. So we’ll see if that gets achieved, but based on model data, yes, it looks like blizzard criteria will be met at many places. For the sake of yourself, stay home Saturday.

How about the coastal flooding?

Here are the very latest tidal forecasts for Cape May, Atlantic City, and Sandy Hook. You can select others from those sites.

I heard this was going to be like Sandy?

Here’s something that agitated me today. I heard from several people somewhat panicked, thinking this was going to be Sandy II. Sandy was a 940 mb monster storm to the south of NJ, that was dragging days of water across the Atlantic Ocean directly into Jersey and New York. This storm will be strong, but it will be moving away from the coast. It won’t have nearly the same characteristics as Sandy did. Meteorologically, it’s like comparing apples to oranges.

But in terms of actual impact what does it mean? It means something worse than what you saw back in October with Joaquin, but short of what you saw in Sandy. It means a lot of water, yes, and major coastal flooding and a top 10 event perhaps. It means problems. The coast is more vulnerable now than it was 5 years ago.

That said, it does not mean mass devastation like was seen in Sandy. So you are right to be preparing and be concerned. But should you panic? No. Make your preparations as you would for any major coastal storm. Remain calm and heed the forecasts of the National Weather Service.

This will likely be my final forecast post on this storm. Thanks for reading and hope you have some time to enjoy the power of nature without being impacted too hard.

Follow me on Twitter @mattlanza.

Jonas 2016: Make Snow Forecasting Great Again

I don’t have any mom texts to run with today, but I do have a map. We’ll get to that shortly. Let’s break things down.

So what’s changed since yesterday, Matt?

Honestly? Not much really. We still have a storm. It’s still early in the game for snow forecast maps, but we can at least make some assumptions. We still have a major coastal flooding issue to deal with. We do have blizzard watches posted, among other NWS watches and warnings. All this means is “prepare for a snowstorm.”

Where are the watches and warnings?

Glad you asked. Here:

012016_snowwarnings
National Weather Service Watch/Warning Map as of 5:45 ET Wednesday

In the East, the purple are winter weather advisories, the blue winter storm watches, the pink winter storm warnings, and the green near DC is a Blizzard Watch. Consult your local NWS office website for what it all means exactly, but the bottom line is a major winter storm is going impact places from Central Arkansas to New York City.

Has the coastal flooding idea changed?

Not really. There have been some forecast tweaks, but overall you’re still looking at a top 5-10 coastal flooding event along the Jersey and Delaware Shore, and possibly for places south and north of there also. Basically, this should be the worst you’ve seen since Sandy. It should *not* match Sandy in most places (though in Cape May and Delaware it’s going to come close), but I don’t want that to diminish the significance. The coast is far more vulnerable in spots now than it was then, so just because it’s not Sandy II, does not mean it’s going to bust. This is a big deal. Here are the very latest tidal forecasts for Cape May, Atlantic City, and Sandy Hook.

This flooding event will rival some of the great nor’easters in memory. Think Ash Wednesday 1962, Halloween 1991, December 1992. This storm will have elements of those storms and it should be treated seriously if you live on the coast or back bays.

Alright, so talk to me about snow.

Here is *my* snow forecast thinking. This is not an official forecast. It’s subject to change, and you should always consult the official NWS forecast or local TV for the most up to date info. Yes, I’m a native of Jersey and spent 5 winters drawing snow maps in Upstate New York when I worked in Syracuse and Utica, but I live in Texas now. I can only do so much.

012016_Snow_Forecast
My snow forecast as of Wednesday evening. Not an official forecast, just my own opinion.

What do I think? Some key points.

The northern fringe of this storm is an absolute nightmare. If you live north of I-195 in NJ or I-76 in PA, this is going to be an incredibly difficult forecast to peg down. The tight gradient in snowfall that I spoke of yesterday is going to wreak havoc. A 20 mile shift in track of the storm (highly possible) could lead to a 6-12″ difference in snow totals, if not more. This is going to be a big problem for North Jersey, possibly the Harrisburg metro area, New York City and extreme southern Connecticut/Long Island.

The Jersey Shore is oscillating between a total mix scenario and a thumping snow. I don’t think this is like the storms of 2009 and 2010, where coastal South Jersey absolutely raked in snow totals. This will be more complex, and I’ve cautiously gone about 3-6″ there, but I do see risk for higher amounts depending on the exact final track.

The thump zone for this will be Northern/Western Virginia through DC and Baltimore. While I don’t expect a uniform 18-24″ in that zone, I do expect some locations to push 30″, contingent on mixing and thunderstorm potential. Other areas will see less than 18″. That’s the nature of snowstorms like this.

Yes, thunder is going to be likely from VA through NJ with this I think.

Winds of 30-50 mph are likely, and some gusts could be even stronger. This will create blizzard conditions. I would not be shocked to see Blizzard Watches expanded tomorrow.

Anything else I should know?

Snowstorms are fun. This one is going to be big, massive, and historic. While fun, it has a very serious element to it that should be respected. If you have plans on Saturday, I would strongly consider rescheduling them. Heed the warnings from NWS. They’re not just throwing this stuff out there. It’s serious.

And please consider taking pictures of something other than your patio furniture. Seriously. Get creative!

Follow me on Twitter @mattlanza.

Your East Coast Winter Storm Run-Up Survival Guide

As a forecaster and communicator, I try and approach my audience a lot like I would my mother. Would my mom understand what I’m talking about? Sometimes I deviate and get nerdy; we all do. But when it comes to the forecast details, it has to be simple, clear, and easy to understand.

So my mother sent me an interesting text message today. She said:

Ok. I’m getting anxious. Or curious. I’ve heard so many maybe this or maybe that’s. I want the truth. I’m sick of speculation.

That’s such a great mom text.

In the run up to this major East Coast winter storm, blizzard, Winter Storm Jonas, whatever you use to describe it, you’re going to get a ton of this speculation.

So today, you’re all my mother, and consider this my survival guide for you.

What’s going on here?

The weather models have been hooked on this idea of a major winter storm in the Eastern US for awhile now. There is good agreement among all the various models we use that something is going to happen. Someone’s getting a major storm.

So how much snow am I getting?

No one can answer that question today unfortunately. What we know is that a number of factors are going to contribute to this storm being loaded with moisture. In other words, someone is going to get a *lot* of snow. It’s just not possible to say who that is yet.

Right, right, I get that, but give me your best shot.

This storm is big, slow, and it has a number of complex parts to it that will make it difficult to peg down until we are closer in than usual. But, some trends have evolved in the last couple days that lead us to believe a few facts about this storm.

First, it will be a *big* storm. That means even if you don’t get snow, you may get impacts. It will be slow moving. It will have wind…lots of wind. It will have major, major coastal impacts. Depending on track, we could be looking at a top 5-10 coastal flooding event for folks from the Jersey Shore into Virginia perhaps. That is a serious issue.

But what about snow? The storm has slowly trended south on the weather models. Additionally, it has a very, very sharp gradient on the north side. In plain English? If you live on the northern fringe of this storm, there’s going to be a razor thin margin between major snow and conversational snow.

Here now, a map of where I think things stand as of Tuesday afternoon. Remember, this is subject to change.

011916_snowrisk
My Own Tuesday Evening Snow Synopsis for the Weekend

The trouble is in New England, New York City, and Northern NJ. The models show a tremendous cutoff in snowfall here. The next map is a weather model’s output for precipitation (liquid, not snow). I’ve focused on the NYC area.

011916_precip
18z GFS Model Precip for New York City area (Weather Bell)

Why am I showing this? Notice how in the Central Jersey area, the model spits out about 1.5″ liquid. Go 50 miles north from there. So, like Orange County, NY? About 0.5″ liquid. A 1″ liquid is roughly equivalent to about 10″ of snow. So 10″ snow difference over 50 miles, and the reality is likely that it will be even sharper than this. You’re talking about (surprise!) a major difference in snow totals likely over a short distance over a major population center.

Bottom line in all this: I have higher confidence in heavy snow hitting Virginia and probably DC right now than I do for the Northern half of NJ, New York, or New England. I don’t focus on North Carolina much since the majority of my family and friends are between DC and Boston. But this has potential to be a big storm in a good chunk of NC also.

Alright, so when does all this unfold?

Snow should start in Virginia as early as later Friday morning, and it probably won’t end until about Saturday night. In Philly, it’s a Friday afternoon start and late Saturday night finish. Add a couple hours to all this as you go north to NYC. I have lower confidence in anything further north, so I won’t speculate beyond this.

What about this coastal flooding?

Yeah, this one goes unchecked sometimes. Snow is way sexier, but this is way more damaging potentially. The NWS office in Mount Holly has done an excellent job highlighting this risk. If you look at storm surge guidance for Cape May, NJ, you’ll see the first high tide cycle impacted late Friday ends up at a water level of about 8.5-8.7 feet. Sandy saw a tide level of 8.9 feet there, October 29, 2011 was 8.7 feet, the December 1992 nor’easter was 8.6 feet. An 8.5 foot tide level would rank in the top 8 all time at Cape May. This one’s big. It’s like a 90’s throwback nor’easter.

011916_Cape May
Cape May Surge Guidance shows a tidal level over 8.5′ Friday night/Saturday AM. This would be a top 10 event without much trouble. (NOAA)

If you live along the coast or Back Bays of New Jersey, Delmarva, Virginia, you should begin planning for the possibility of 2-3 high tide cycles like this. If the storm track shifts a bit or the intensity changes, we could see these values change. It’s a fluid forecast, but it’s a serious issue along the coast. Follow your local NWS office for info and guidance.

So will it be a blizzard?

Maybe for someone. It’s entirely possible, but specific criteria must be met regarding wind speed and visibility. It’s too soon to say exactly where and who or how long, but it’s a distinct possibility.

That’s all for now. Feel free to ask any questions and follow me on Twitter at @mattlanza.