Saturday, October 27, 2012

9:50am Saturday: Hurricane Sandy Update


That's Hurricane Sandy with the eye east of Cape Canaveral. Maximum sustained winds are 75 mph and the pressure is 960 millibars.  It is moving slightly east of due north.

Because this is going to be a rather long post, I'm going to break it down by hazards to try to make it a little easier to follow.

Location

The center of the storm will likely come ashore in the area shaded in blue.

However, the location of the center is much less important than in a more typical hurricane. In the case of Sandy, the storm's winds will be hugely spread out.

To illustrate, take a look at this forecast valid at 8pm EDT Monday from the European model.

If you consider the red to be wind gusts strong enough to cause power lines to fall, there could be power failures from Richmond to Portland. Very strong winds for Wilmington, Philadelphia and into NYC are forecast. Now, I don't want you to take this position literally. It could be a little farther north or south. The point is that dangerous winds, if this forecast is correct, will cover a vast geographic area rather than being concentrated within 10 to 25 mi. of the eye as in a typical hurricane.


Timing

In eastern Virginia, far northeast North Carolina and DelMarVa, the winds will begin rising Monday morning, perhaps even before sunrise. In other areas, the winds will increase during the day Monday.

As I have said many times, if you have plans to fly through an airport north of Raleigh and east of Pittsburgh Monday or Tuesday, forget it. Even if the airline runs the flight in, the risks of getting stranded at the airport in a last-minute cancellation are too great. Wednesday will probably be a mess, as well. Route around the storm. You can learn how to do all of this in my Airline Crisis Survival Guide.


Wind

We really are in uncharted (literally) territory here for two reasons:
  1. The forecast barometric pressures are the lowest in history in this part of the world. Because there is a strong correlation between the rate of change of barometric pressure (known as the "pressure gradient") and wind speeds, there are no past histories to draw upon.
  2. We don't know if our tools, because they have never been tested with a storm of this nature, are giving us accurate barometric pressure forecasts.
So, I've got to give you my best scientifically educated estimate.  The map below is from my colleagues at AccuWeather who are following the storm and I suggest you visit for a second opinion. This could shift a little north or south. 
Note that the highest winds extend into coastal New England. There are two things about this map I wish to stress: Somewhere, there will be gusts above 80 and perhaps 90 mph. If a thunderstorm complex can mix some dry air down, there will be a gust to 100 mph somewhere in this region.  The second aspect is that the winds will continue for hours and that pounding will contribute to the overall damage. 


Coastal Flooding

In two national news articles yesterday this wasn't even mentioned! I really fear storm surge is being underemphasized in the news coverage. Here is AccuWeather's map.
The 5-10' storm surge doesn't seem like much until you add two feet for the full moon and wave action to 20' or even more. So, do the math:  

10' (surge) + 2' (lunar) + 20' (wave) = 32 feet above sea level

That's right, there could be spots where ocean water gets to 32 feet above sea level! Can't tell exactly where that will be yet, but if you live near the coast you need to be prepared to evacuate. Be working on that now!


River Flooding

Fortunately, most of the region has been relatively dry the last few weeks. However, enough rain is going to fall in some areas that river flooding will develop.  
National Weather Service


Snow/Blizzard Conditions

The shaded counties are under a winter storm watch. The watch may need to be expanded as the storm's path becomes more certain. 

From Greg Carbin and NWS, here is the spread of snowfall amounts for Elkins, WV:
Before you say, "Whoa, that's a spread of 5" to 35"!" let me say we agree with you. We aren't used to forecasting snow in tropical weather systems. If the cold air gets into the system soon enough and deep enough, yes, more than three feet of snow will fall. The combination of wet snow and high winds will cause power failures in this region if the heavier snow amounts indeed occur.  


Tornadoes

Probably some, but impossible to estimate where.  


So What Do I Do Now?

There are a number of good lists out there. Here are my suggestions: 
  • Get prescriptions refilled now, especially if you doctor must approve the refill. 
  • If you have a relative at home that requires electricity for life-assistance purposes, you may want to move he or she outside of the higher wind zone. 
  • Vote Monday morning if you can safely do so. If the stronger models are correct, power could still be out in some paces on Election Day. Regardless, that is one less thing you will need to do. The election will not (and shouldn't be) postponed. 
  • If you can get an electrician to install a generator, get it done. Do not try to install a generator yourself. 
  • If you don't have a generator, get a power inverter or two. Radio Shack and similar stores sell them. They are a "poor man's generator" and will keep your cell phone, laptop, and similar items charged. Tell the person in the store what you want to run off it so you get one of the right size. Do not try to run the inverter for hours at a time as that is tough on your car's battery. Charge the (for example) cell phone and let the charge run all the way down, then use the inverter to recharge. 
  • Keep your car's gas tank full. 
  • If you have a wood-burning fireplace and you know your chimney is clear, get wood. Keep some indoors to keep it dry during the storm. You may need it to heat your home. 
  • If you live in a 100-year flood plain (you can check at city hall or your library) or on the coast figure out your evacuation strategy now. Make your list of things you will take with you. Be prepared to leave at short notice.
  • Fill a few gas cans (the type you would use for your mower) to have extra in the event of power failures. 
  • Purchase extra food staples. Without power, stores will be closed. Things that require less preparation are better. Bottled water is especially important. 
  • Purchase booster batteries for your cell phone and other essential equipment. If you need insulin or other medicine that must be kept chilled make plans now. 
  • Consider what you would do if you were without electricity for a month. If you have an invalid living with you that requires electricity, there will be areas that will be without for weeks. Be proactive. 
  • If you live in a heavily wooded area, does someone in your vicinity have a gasoline-powered chain saw? Does it have fuel and a reasonably good chain/blade? Test it, now. 
  • Get to an ATM. Without power, credit card readers and ATMs will not be working. In a disaster, cash is king.
  • Addition: If you are in the high wind area, thoroughly photograph your home and possessions now. You will need it for insurance purposes. This includes trees, shrubs, etc. Then, if using a digital camera, upload to internet so it will be there after the storm in case the worse happens. 
Stockpile some good books, magazines, board games and keep a good attitude. Look at this as one of life's adventures.  

Good luck!!


Addition: Just got an email asking why I didn't mention candles, Coleman lantern or flashlights (and batteries). It was because I assumed, perhaps, incorrectly that every household has those, hurricane or not. If you don't have them, please add them to your list. Make sure the batteries in the smoke detectors are good, especially if you are going to be using candles.

Second addition via AccuWeather's Jesse Ferrell:  Here is a storm surge map of NYC. Note that Staten Island and Lower Manhattan are both flooded using the National Hurricane Center's latest track forecast.
click to enlarge
I hasten to point out that this forecast could change if the forecast track or intensity changes. I'm posting this to illustrate the serious nature of Hurricane Sandy. Here is the forecast water heights for Bridgeport, CT:
Yes, that is 15.5' above sea level without including the wave action.  

8 comments:

  1. I think you're a week early with your Election Day suggestions.

    ReplyDelete
  2. Not if power outages due to this storm last through Election Day, which very well could happen if some of these forecasts are correct. Keep in mind that electronic voting, sometimes without any paper trail, is the norm in many areas now.

    Elaine

    ReplyDelete
    Replies
    1. Elaine,

      Mechanisms exist to accommodate election disruptions due to national emergencies (which this storm could be.)

      Although if people can vote early, probably no reason not to.

      Delete
  3. Good post.

    However, the election is not for another week. :)

    ReplyDelete
  4. @Debbiy: I'm well aware of the date of the election. However, many states allow early voting and absentee voting. Given that power failures may persistent in some areas through Election Day, it makes sense to do it early if local laws and meteorological conditions Monday allow.

    If you are holding an absentee ballot, mail it Monday.

    ReplyDelete
  5. Agreed.

    I've been watching this storm for ~week (I have a great fondness for late bloomers) and it took me nearly a day to remember the election is the FOLLOWING week. I'm sure I'm not alone. We are all so desperate to have this over with... :)

    ReplyDelete
  6. I realize this is completely shameless self-promotion, but might I recommend my iPhone/iPad app for home inventory management? It has a cloud component:

    https://itunes.apple.com/us/app/tmi-manager/id426861163?mt=8

    It works well, and is cheap. Sorry if this seems crass, but it really is a good solution, and seemed to be the right fit for your point about taking photographs of your home and possessions for insurance purposes.

    ReplyDelete