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.

A Year of “Extreme” (Duration) Disasters

This year has been interesting in a number of ways from a meteorological standpoint. It’s been tragic from a human standpoint…and it’s been extreme. And I’m not talking about what you may think. The disasters of 2011 have been, for the most part, either extremely quick to occur…or painfully slow. Tornadoes? Almost instantaneous. But drought and river flooding? Slow enough to the point where a lot of meteorologists call them “boring.”

Hydrograph/Forecast of river levels on the Missouri at Williston: http://water.weather.gov/ahps2/hydrograph.php?wfo=bis&gage=wltn8&view=1,1,1,1,1,1,1,1%22

We’ve had the flood on the Mississippi already. But in progress at present is another extreme flood, this time on the Missouri River. To the left is the hydrograph and forecast from the Missouri at Williston, ND…already at a record level and only forecasted to rise further. This winter has been a perfect storm for this sort of setup. With one of the strongest La Ninas in recent memory in the Equatorial Pacific Ocean, snowpack was high in the Upper Midwest (not unusual). The melt of that, combined with a period of extreme rains from March and April’s severe weather helped push the Mississippi to record levels. La Ninas also traditionally hammer the Northwest US with heavy snowfall. This year was a late bloomer, but when it hit, it didn’t stop from late February through mid to late May. That melt in the Northern Rockies is helping to fuel this record flooding scenario. The meteorological factors coming together this past winter/spring have really not happened since the 70s and possibly not to this level since the 30s or 20s…so it’s not a huge surprise that years from those decades are the years a lot of these records were set.

Speaking of the 30s…similar factors seen in the Dust Bowl era seem to be helping to fuel the epic drought in the Southern US this year.

US Drought Monitor's Map of Texas from Today

The map to the right shows the drought in Texas. The D4 (exceptional drought) area from the US Drought Monitor is currently in place across an uncanny 57.83% of Texas. These are tremendously high numbers that will likely only continue to get worse unless a tropical system impacts the entire state (because I don’t think daily isolated thunderstorm activity is going to really help this). D4 areas are also present across Louisiana, Oklahoma, Georgia, Florida, and New Mexico. With that La Nina, while northern parts of the country bask in precip and snow, the South usually ends up dry. Western Arizona into Southern California were a notable exception this year, but from Eastern Arizona (where the tremendous wildfires are currently burning) through West Texas, the La Nina helped to serve up dry misery.

These events are certainly troubling and certainly tough to swallow, especially if you live in those areas. But they are really far from unusual. They have happened in the past and will likely happen again in the future. The law of averages in weather:

Normal = ((Negative Extremes + Positive Extremes) / Number of Events)

There is no such thing as “normal” weather. While droughts and floods may be slow moving and “boring” though, they are costly, miserable disasters.

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Cold, Flooding, Snow…Just Another Spring!

Trying to hit a few key issues today. First, the potential for accumulating snow in the Mid-Atlantic over the weekend. It’s snowed, sleeted, thundered, etc. across much of the Mid-Atlantic and Northeast in the last 36 hours…why not add something else to the mix?

12Z NAM Snowfall Forecast (From Earl Barker's Site: http://wxcaster4.com)

Map to the left is the NAM model depiction of snowfall for the next 72 hours. It shows you snow stretching from Omaha to Kansas City to St. Louis to Louisville to Cincinnati to just south of Washington, DC. This has been shown off and on throughout the week on all the models. It looks like we’re game on for a snow event. The problem is (of course) the exact storm track. The GFS forecast is *slightly* further north, which would bring more snow into DC and much less around Richmond. I would side in between the two right now…with light snows south of Baltimore to south of Richmond, with an axis of heavier snow, probably in the middle, through, say Fredricksburg, VA. Could be a decent event for the  northern part of the Blue Ridge. This will not be a *major* event, but given that it’s almost April, every snow event is extra painful.

So if you have weekend plans, specifically Sunday, keep this in mind. It is the time of year where it’s tougher to get snow to stick on the roads, but given that we’re leading into this event with several cold days, we could see more sticking than we normally would in late March.

In other news, spring may be delayed somewhat in the East. Just got a look at the latest weekly forecast from the European model…and, yeah, it looks cold if you live anywhere north of about Florida. Not guaranteed to verify, but this is certainly not what you want to see if you live in the Northeast, Plains, Great Lakes, or Mid-Atlantic.

However, this may help slow snow melt some over the northern tier…which is good because the latest river forecasts show major flooding likely on the Mississippi near St. Paul. Could be another painful Upper Midwest flooding season.

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Threat for Next Weekend Remains

PSU E-Wall 00Z GFS Forecast Next Sunday Evening

I’m a major proponent of NOT hugging models, but there’s no question that tonight’s 00Z GFS run was encouraging. The map to the left shows the GFS forecast for next Sunday evening. Keep that in mind…that’s a week away. We all know how fast that can change, but to see both the Euro and GFS in agreement on an approximate track/style of storm here is encouraging. Taken literally, this would be a significant snowstorm from DC-Boston and for most/all of NJ. I wouldn’t take things literally, but I want to at least bring the idea that this is a possibility to your attention.

We’ve got a ton of energy swinging into the West Coast, and ultimately that’s going to be the key to this I think…how that energy gets directed inland and across. And a couple things to note: Models notoriously handle this sort of energy infusion into the Pac coast poorly. And the ridge in the West is a bit flatter and less amplified than I’d really like to see to generate a big East Coast storm. So the big problem with seeing a great storm like this seven days out is that everything can go wrong between now and then. More on this in the coming days.

One thing the GFS certainly does though is continue to provide reinforcing shots of cold weather to the Eastern half of the US through the end of the year. Obviously, that’s something else you can’t take literally, but winter doesn’t seem to want to let up. And with the off the charts AO and strong NAO blocking in place, this makes some sense. Stay tuned.

Lastly, cool video to end tonight that I just found. Heavy rain in Washington State and the Northwest has produced significant flooding around Seattle and elsewhere. Here’s video of the Stillaquamish River at Granite Falls in Washington…flooding…and this is absolutely massive.