Saturday, August 27, 2011

Hurricane Irene Forecasts and Their Hurricanes Versus Our Hurricanes

The media is hitting Hurricane Irene really hard and some descriptions are going too far: "historical storm", "storm of the century", etc.  Folks, this a category 1 storm with sustained winds of 85 mph.  Serious, but not catastrophic.  We are already seeing local authorities overreact--like NYC cutting off bus and subway service at noon EDT.  At that time the winds at NY's Kennedy Airport were 8 miles per hour and there are only a few showers around.   The strong stuff will not happen until tonight, so why cripple people's ability to move around and for coastal people to evacuate?  Overreaction stemming from massive complaints about poor snow removal last winter?

A key reason for my field to improve forecasts is to reduce the overwarnings and overreactions--which undermine confidence in forecasts, resulting in calls of "crying wolf" and lessening public reaction when truly threatening situations are imminent.    Many of us worry about situations such as the SE tornadoes when forecasts are very good, but many people still die.  And more limited and surgical warning save money.  Big money.  The trouble, of course, is that the media loves to overhype storms...really good for viewership.

For those of us on the West Coast it is good to keep some perspective on storms.  We don't have tropical hurricanes, but our big storms are the equal of all but the strongest hurricanes. Take Irene..fairly large hurricane with sustained winds of 85 mph and a central pressure of 952 hPa (mb).  Here is a nice image of it:


Lets compare to our Dec 12, 1995 windstorm.  Here is an image:


Ours is just as big if not bigger.   Maximum winds?  Here is a nice analysis by storm-maven Wolf Read:

Gust to well over 100 mph on the coast!  Certainly, the winds from this storm are in the same league or greater than Irene.  Central pressure of our storm--953 hPa...virtually the same as Irene.  The 1995 storm is nothing compared to the 1962 Columbus Day Storm.
And the waves from our big storms generally eclipse those of the East Coast varieties.

A major difference between our storms and East Coast hurricanes is the coverage--for many reasons the WeatherChannel and East Coast media give relatively short shrift to our storms. 

But hurricanes do bring heavy rains and flooding, which is generally limited for our big windstorms.  The reason--hurricanes are tropical systems depending on warm water and the release of heat by condensation of water vapor.  Our storms derive their energies mainly from another source:  horizontal variations in temperature.  And the coastal areas of the east coast are more vulnerable to storm surges and coastal flooding--the biggest threats of hurricanes.








34 comments:

Beth Niquette said...

Hey, Dew! I was thinking the very same thing you wrote--thanks for putting it into words!

I read online that the weather folks think we're about due for another big wind storm this winter. I sure hope not!

Take care, and thanks for your thoughts on this.

Paul said...

I think there is more to the timing of the decision to shutdown the NYC subways than meets the eye. Idle rolling stock is stored in rail yards threatened by storm surge flooding. They are moving this to parts of the system relatively secure but these involve mainline trackage. Maintenance equipment needs to be prepositioned to fix problems. All this takes time to put in place.

Paul Middents

julie said...

Isn't part of damage of the winds their sustained nature in a hurricane? 60 mile an hour gust in winter at our house is not unheard of here in Seattle on Puget Sound side, but sustained winds of that that for hours would be more damaging to house, trees, etc. As structures that could do fine for awhile might not due to duress over time.

As to NYC, we heard it takes 8 hours to close the transport system. Maybe overhyped as storm, but if you don't live with any preparation, you have some catch up to do compared to people we know in Virginia and North Carolina who go about their "usual" hurricane preparations.

julie said...

Isn't part of the seriousness the fact that the high wind is sustained for so long? Not unheard of where we sit up high here in Puget Sound to get 60 mph gusts at our house, but it would be more damaging if that went on for hours. Can't imagine our back fence would last. didn't one year.

While I agree everything gets exaggerated importance on east coast because of population density (smaller form of that is true here in news reported in Seattle or Spokane with rural WA news ignored, not reported) there is a different level of seriousness to humans if there are 8 million in relatively small geographic location.

Synthetic Zero said...

The reason they're shutting down subways at noon is it takes about 8 hours to move all the trains in place for storage.

101469739241303430199 said...

Thanks for the explanation for the early NYC transit closure, Paul. Looking at the storm surge probability maps (zoomed in for NYC) (http://www.nhc.noaa.gov/psurgegraphics_at4.shtml?gm) it looks like >90% probability of 2 foot surge, and 50% probability of 4 foot surge in large parts of the city near the waterways. If the models are anywhere near accurate, it is prudent to prepare based on warnings rather than wait to respond after the fact.

Just AboveNOAA said...

Did you see that nbc/king actually sent Jim Forman to the east-coast ("have 'parka' will travel")?

Our weather is currently just too $@#!n boring to report, it seems [wink]

larchitech said...

I was in a seminar in Newark recently and they did have a subway tunnel flood as recently as the 1980's that took 10 days to get back into operation. The speaker also said that the area around the world trade center is a bathtub below sea level and it wouldn't take a lot to flood that. A storm this size could easily do that and that would lead to flooding the subway. I agree with the others about getting the rolling stock to higher ground, but the buses too? I saw one couple on TV and they were evacuating by bicycle since that was the only form of transportation they had. The didn't seem to mind though. The said it was the fastest way to get out of town.

Cliff Mass Weather Blog said...

Folks....let me tell you why I think this is overhyped. Look at the sat imagery...this is not a well-formed storm. Much of the circulation is over land...it is going to weaken now. The NY folks could have delayed closing their system for at least 6 hrs and still have plenty of time. They are crippling movement in a major city...including people who want to move to safety. The roads then get hammered. ....cliff

julie said...

Just watched some you tube video of the hurricane taken from the space station. They had problem with sound on a couple of the videos, but images pretty spectacular. Would be interested in Cliff viewing and commenting on what they are seeing and describing. Certainly gets across the massive size of Irene. And without having to listen TV news folks to see something. Space station crew are nicely low key and minimalist commentary.

Kevin said...

The planners may have been able to delay the closures of the transportation systems and been okay. We will know in 24-48 hours and refine the decisions in the future. As forecasting gets better, and it will, evacuations and closures will improve and be better targeted. It would be better if the media would explain what is involved in closing the subway system.

renepeterson.info said...

Well, Cliff, NOAA says the present forecast is for near or at hurricane strength when it hits NYC. I don't believe that NOAA is given to hype but you have more insight into the politics and science than I do.

However, I'm a New England native (Connecticut and Cape Cod) and have experienced my share of hurricanes. I have also lived here in the Seattle area for over 18 years. In density, topography, and attitude the two areas could not be more different. Folks in NYC were told two days ago to start evacuating the low-lying areas. And they were told that the subways would close. Then NYC made all public transport FREE and ordered taxis and all transport to accept animals too.

The population of NYC has over 8 million people in 350 square miles - and that does not include Long Island or any of the surrounding boroughs. This is less of a "weather" problem and more of an "weather vs old infrastructure and high population density" problem. All of Washington State has a little under 7 million. I find it is very hard for people here to truly understand the density on the East Coast. There is nothing remotely comparable.

As far as topography, the WA coastline comparable to NYC is the Olympic coast which is nearly devoid of population and development - hence not many huge problems despite huge storms.

I believe that NYC is doing the responsible thing and doing it well, but I can see how people from outside the East Coast might perceive it as an overreaction. It might interest you to know that none of my friends and family view any of the official policies and recommendations as an overreaction.

Let's hope you are right and this storm breaks apart quickly. I know I'm praying for it as I keep my fingers crossed for all my friends and family along the eastern seaboard.

Susan said...

Cliff, I understand that the news is hyping up the story, but I believe that some people can be in denial of the danger, and the need to be able to be able to survive without power for days. I heard that some that were staying, I think in NC, had to sign waivers and advise next of kin. Unfortunately some will always want someone else to blame when the unexpected happens. Getting as many people to somewhere safe, and with power is important.
Thanks,

JewelyaZ said...

With all due respect, Cliff, a lot of the hype was generated when Irene was a category 3. Most of us do not live at the coast at <10 feet above sea level... but that describes a huge population along the Atlantic seaboard, including a lot of Manhattan. We just don't have the population centers that the east coast does right on the ocean.

As you point out, our "hurricanes" don't include the massive amounts of rain that say Irene did. And the coast there is an entirely different kind of terrain.

Do I think folks overreacted in NYC? Yes, a little bit. Have I lived through hurricanes in North Carolina and the big storms here? Yes. I have to admit that the ones on the east coast are MUCH scarier because of the associated thunder and lightening, the rain, and the flooding. Hurricanes have strong wind for hours and hours... Irene's winds near the landfall will have been over 10 hours hurricane strength in one direction, a break for the eye, and then about 8 hours hurricane strength in the other direction... our storms don't do that! Also, it goes without saying that in Bellevue at 210' above mean sea level, I don't need to be scared of the 11' storm surge, which wasn't the case in Emerald Isle where I rode out one hurricane.

As for the NYC subway, it's not like you can say, "oh crap! We need to shut it down!" and do it in an instant. It actually takes about eight hours to shut it down properly so that rolling stock and people are left in safe places and no passengers are stranded. It also then takes about eight hours to get the system up and running again. The potential for damage to millions of dollars of equipment, miles of track, and the fact that so much of the subway lines are well below sea level all help drive the decision, which cost a fortune and I'm sure would be criticized either way.

EBoperator said...

Here are some photos from MTA preparing for Irene. This may help explain why they could not wait. http://www.flickr.com/photos/mtaphotos/6085662147/in/photostream/

bhd said...

Cliff, you're aware, of course, that there are many communities along the east coast - particularly in NJ - that sit at and below sea level. These are coastal plains and barrier islands. Wind is not so much a factor in this storm as the long-lasting, seriously heavy rains - along with an astronomical high tide. Transit routes are going to be flooded - but good - and from the heavy rains from the back end of the storm. I think the preparations for this storm are right on the money considering the widespread expected flood devastation.

Cliff Mass Weather Blog said...

All I can say is...wait until tomorrow. ...cliff

Paul said...

Cliff,

I am disappointed in your take on this. You are second guessing before the fact from a position remote and devoid of responsibility. I think the timeline for these efforts exceeds your crystal ball. You should be applauding timely efforts even if the storm doesn't live up to the hype.

You brutalized the Seattle city fathers for their lack of foresight in snow removal (maybe rightly so) yet criticize timely efforts to protect NYC transit systems while also providing for housing folks at risk and moving people out of areas in hazard.

These are tough calls. Friday morning quarterbacking from the left coast doesn't help.

I love your blog and am looking forward to your KPLU stint but I think you are off the reservation on this.

Paul Middents

JewelyaZ said...

Cliff, there are already nine people dead BEFORE the storm really gets to New York City or Boston. There was a tornado on the ground in Delaware that damaged more than a dozen homes. There was a tornado on the ground just outside Philadelphia. Can you imagine what would happen if we had tornadoes on the ground in say, Tacoma and Shoreline, DURING one of our big windstorms? Our windstorms don't generate tornadoes at all, as far as I know.

I know Irene doesn't look like much on the radar, I will give you that. But you are comparing apples to oranges by comparing our windstorm "hurricanes" to real hurricanes in the Atlantic basin, at least in terms of what they mean to people. All you have to do to really compare is look at the death toll and the financial damages. Our storms are mighty meteorologically, but in human costs, the Atlantic hurricanes are MUCH bigger events.

Is this "the storm of the century"? No. But it does point out very clearly, if one is willing to look honestly, exactly how vulnerable our transport systems, power-generation and transmission facilities, and living environments are when millions of people live and work on what are essentially coastal plains and barrier islands. Were a Category 3 or 4 to come up the coast, the death toll would rival Galveston. I know in your heart of hearts that you do not wish that kind of storm on people that live back East, though you have come very close to calling them crybabies and/or of overstating danger.

I think this might be the first time in all the years I've been reading and listening to you that I think you are nearly completely wrong. Have you "sheltered in place" through a hurricane, Cliff?

smokejumper said...

The vort max moving through Oregon tonight is just as big as hurricane Irene, lol. FEMA listed lightning as a top harzard of a hurricane, insane.

This sums it up...but a weather channel correspondant talked to a girl teenager, and she said, 'this is it, we had a stronger storm than this last week'

Cliff Mass Weather Blog said...

Paul,
My point is that they closed down the city way too soon, with a huge impact economically and hindering the movement of people out of the way of the storm. It just didn't make sense. ...cliff

Unknown said...

JewelyaZ-

Just so you know I searched all day yesterday and did not find one, NOT EVEN ONE hurricane force wind at any ASOS station anywhere along the eastern seabaprd. Not where Irene made landfall, and not anywhere else.

This was an over hyped storm, and this track storm has taken place before and with more strength.

NYC had about a 10 minute period where the wind sudenly gusted to 52 knots. Most of the day it was gusting 25-33 Knots.

For NYC this is a storm similar to what we get every year here, wind wise.

In no way was this worth calling this storm a "historic" storm, and in no way did it ever present "extreme" danger as the media wanted to hype.

This is a track that has been duplicated many times in the past, and will be duplicated in the future, and with stronger storms.

Also, most of the lightning was OFFSHORE, in outer bands away from the eye, and not a lot of it also.

Dont get me wrong it is a noteworthy storm, and powerfull.

But this storm was not near the threat to NYC that the media was claiming, and the worse thing is this: weather geeks knew this fact and yet the media hype machine won over the listening public easily.

Its pretty sad that this is how it works.

LorbeerTLC said...

Shifting gears here,
Cliff, I'm interested in comparing this storm to a Nor'Easter.
-Tom

weatherlover said...

I agree that Irene was a little overhyped, but I think that as they keep saying on the news, "It's better to be safe then sorry." Some of the earlier forecasts showed Irene coming ashore in North Carolina with sustained winds of 115-120 mph. Then it showed the storm hitting New York during the astronomical high tide as a weak Cat. 2 or a strong Cat. 1. Only some of our bigger storms such as the Columbus Day storm can be compared to a Category 3 hurricane.

As you said in your post on the 23rd the intensity forecasts were off and Irene came ashore "only" with sustained winds from 85-90 mph. That still did quite a bit of damage especially when you add the tornadoes that came with Irene. Then the storm fizzled out and came ashore in New York as a tropical storm with the worst damage being some minor flooding, power outages, and downed trees.

Just think though, what would have happened if the media had not made it sound worse than it was. Everybody on the East Coast would have gone down to the beach to feel the wind. You would have had people surfing in the waves and other people swimming so they could say "I experienced a hurricane!" With that there would have been a lot more water rescues and deaths.

Basically it was a storm that was a little overhyped and one that you don't want to have here too often, but the forecast showed it was going to be a strong storm and the overhype probably saved peoples lives.

SC said...

From what's been going on today, I'd say Dr. Mass was right and a lot of you were wrong.

Tropical Storm Irene (not even a hurricane) is still churning north, but despite the hype, it looks to be more a of blip than a BOOM in our memory of weather events.

As to the deaths, while tragic, it's not surprising given population density. I'm strongly against media hype and it's been obvious for days that Irene was on a track to weaken substantially. The problem is the news is about NOW, NOW, NOW, and not about the future. That's hard on weather forecasts when a category 3 storm will hit as just a middling tropical storm.

This turn of events is a reminder of why we're reading the blog of an expert. Maybe next time we'll give the blog's take more credence than Catastrophe News Network (CNN).

Harrison said...

Thanks for offering some perspective on this. Just watching the weather channel on Friday night and Saturday morning - I wasn't all that impressed, so I turned it off. Seemed like the storm was far weaker than was hyped. Our storms in the fall and winter can be just as powerful, if not more powerful. Put someone on our coast in November and the same intensity can be found. Since we're in the West, no one really pays much attention to our storms. Well, you do! :)

JewelyaZ said...

Cliff, here's real information about the transit shutdown. The New York Times thinks it was a SMART move made by local experts.
NY Expects Lengthy Recover of Transit System

RLL said...

Cliff - you know some academic in emergency management who could weigh in on this. Not so much opinion, as a discussion of the in and outs of closing major services such as surface and air transportation.

Just AboveNOAA said...

a'yep: Hurricane Irene Mostly a Storm of Hype
when politics confronts science and statistics; emotion wins every-time.

Cliff Mass Weather Blog said...

Imagine if the storm ended up much more serious than expected and more people had to be evacuated. With all transit stopped, traffic would quickly turn to grid-lock. In such situations it is CRITICAL to keep mass transit working as long as possible. Furthermore, as noted in the NY Times the cost of shutting down the city was huge...in the billions of dollars. When the trains were shut down at 12 PM it was absolutely clear that strong winds would not reach NY until after midnight and certainly not much rain until 9 PM. Keeping mass transit going through 9 PM would have been conservative and would have given the city Saturday to work and prepare. I have family in NY--on Saturday they helped run an outdoor garage sale and Friday night went to a wedding...no problem!

Plus, it was also clear mid-day Saturday that the storm was going to weaken--too much of its circulation was above land, the rest was passing over colder water, and the storm was starting relatively weak (cat 1-2). The eye was practically non-existent. There was no way this was going to be a repeat of 1938.

Particularly problematic was CNN's "meteorologist" Chad Meyer, who mercilessly hyped the storm and stated completely wrong "facts" on a number of occasions.

robinc said...

Cliff...You are quoted in an a NY Times article on the hurricane--http://www.nytimes.com/2011/08/28/us/28forecast.html?scp=1&sq=fountain%20henry&st=cse

Strange the NY Times thinks you are expert enough on hurricanes to be quote, but some people commenting here think you should not talk about it.

Nick said...

Honestly, I don't see much wrong with the decisions made in terms of the NYC evacuation. The risk was high enough to justify everything that was done and the city will recover from it just fine. NYC seems to know how to run their city, so I leave it to New Yorkers to voice any complaints to their city leaders. As for the hype...the NYC hype was ridiculous, but this hurricane is certainly turning into a major disaster throughout the inland areas of all of New England in terms of the enormous flooding. Wind was nothing, flooding is everything.

julie said...

The news channels are so predictably overhyping that it must be difficult for government entities to get across accurate useful information to citizens.

To SC, I think Cliff was right about the storm being overhyped and is an incredible authority and educator about weather and it's science. He has opinions about local government management where I doubt he would describe himself as an expert. So I think it is possible to respect his scientific knowledge and take issue with his opinions and conclusions about governance especially in an area as complex as NYC.

In fact it was something that you said Cliff that made me think Bloomberg et al were prudent given limits of what could be predicted. You were quoted in the Times as saying that tracking prediction has improved greatly, but information about wind speed in the hurricane is still very difficult to predict accurately. Those little unmanned drones from earlier post were quite amazing. Do you see this or other technologies coming on board soon to help increase information about these events?

Jim S said...

Another perspective, with preliminary numbers to put the magnitude of loss of life and damage from Irene in perspective:

http://fivethirtyeight.blogs.nytimes.com/2011/08/29/how-irene-lived-up-to-the-hype/?hp