Hurricanes and Global Warming

Somehow, I missed this November, 2011 posting by NOAA’s Dr. Chris Landsea on his thoughts regarding global warming and hurricanes.

He believes that in a warmer climate the number of hurricanes will go down but, of the remaining hurricanes, some will be of greater intensity due to global warming.

Chris is a scientist I greatly respect and recommend reading his comprehensive post.

Record Set: Absence of Major Hurricanes in U.S.

Roger Pielke, Jr.

Today is the last official day of the 2011 hurricane season. The biggest news this year was Hurricane Irene which was a weak storm that caused catastrophic flooding in the Northeast. But, Irene was relatively weak.

My friend Roger Pielke, Jr. has an interesting blog post about a new record we are about to set: The longest period without a major (defined as category 3 or higher) hurricane striking the United States will be set on December 4 and the record number of days will increase each day until at least the 2012 season begins next summer. Roger asks the question: Who would have predicted this in the wake of Katrina when the pro-global warming people were predicting ever more frequent and severe hurricanes? 

Of course, in the comments to Roger’s posting, there is the usual attempt to find some reason to find something wrong with his point:

Except that worldwide hurricane activity continues at below normal levels as calculated by Dr. Ryan Maue:

click to enlarge

The point made, multiple times, on this blog stands: There is no scientific evidence of a significant increase in major storms either in the U.S. or worldwide. 

Tiny Plane Tackles Big Storms

The National Oceanic and Atmospheric Administration (NOAA) now has a tiny aircraft to help study hurricanes.

Sun-Sentinal photo

The aircraft is 3′ long and weighs eight pounds. It will be dropped into the eye of hurricanes so it can fly to 100′ of the ocean (far too low for humans to safely fly). The goal is to gather data that may help us improve hurricane intensity forecasting.

Details from the Sun-Sentinal

Tales of Heroism in Hurricane Irene

A number of people gave their lives to rescue others during Hurricane Irene. The Wall Street Journal is publishing three stories on that topic in the Saturday-Sunday print edition. Below are links to two of the articles from their online edition. They, and their families, deserve our prayers and support.


Some government workers lost their lives while trying to prevent flooding or help others. Michael Garofano, 55, a veteran at the Rutland, Vt., public works department, went to the town’s water reservoir on Sunday afternoon, apparently to make certain a valve built to keep Mendon Brook from flooding into the local water supply was properly closed. He took his son Mike, 24, along for the ride. It isn’t clear what happened, but the brook rose suddenly and both men were swept away. Mr. Garofano’s body was found downstream on Monday. His son is presumed dead; his body hadn’t been recovered as of Friday.

First of two articles from The Wall Street Journal

That Michael Kenwood was willing to wade through dangerous floodwaters in a rescue attempt was no surprise to those who knew him. They say the 39-year-old lawyer and computer consultant was passionate about his volunteer work as an emergency medical technician for the Princeton, N.J., First Aid & Rescue Squad, and trained for water rescues.
His devotion cost him his life on Sunday, in a rescue attempt on an overflowing creek during Hurricane Irene. He left behind his wife and toddler daughter.

And, the second article is here.

Neither Rain, Nor Sleet, Nor Irene…

Walking 8 miles a day to get the mail out! Way to go, Ms. Roberts.

From WCAX TV, Burlington:
Mother Nature may have knocked out phone service and power to these communities, but she can’t stop the postal service.”There is no incoming mail at all because no truck can get to that post office,” Gaysville postmaster Kelly Roberts said.So Roberts hikes 8 miles a day through these hills collecting outgoing mail. Her dedication opens communication with the outside world.”Well hey, mail must go through. Absolutely,” she said.

Wrap-Up on Irene

I believe it is now clear to everyone that Irene was not “overhyped” by weather forecasters,

Associated Press photo of what used to be Route 4 in Vermont

with approximately 6,000,000 still without power 4-5 days (depending on location) after the storm and communities still cut-off from the outside world, I want to close out Meteorological Musing’s coverage of Irene with a remarkable time-lapse of Irene with  the National Weather Service’s path forecast superimposed.

Hat tip: Andrea Bleistein

While they were not perfect, I’m very proud of my colleagues at AccuWeather and the National Weather Service for superb forecasts of this dangerous storm that unquestionably saved lives and dollars. The meteorological profession came through again.

I’d now like to talk just a moment about preparedness. The Wall Street Journal has an online story just posted about “slow pace” of the recovery.

Political leaders encountered frustrated residents in the northeast Wednesday, angered by days without power, continued flooding and what they perceived to be a slow government response to Hurricane Irene’s devastation.
More than 1.8 million homes and businesses from Virginia to Vermont remained in the dark—with some people told they may not have power for days…

Standing with her school-age son and daughter beside her, Andrea Trout said she had Type 2 diabetes and was struggling to keep her insulin at the proper temperature because her refrigerator lost power. “I’m feeling afraid,” she said. She has been in the dark since 7 a.m. Sunday.

I absolutely, totally feel for these people. But, rather than complain to politicians (which is the topic of the story), I would like to suggest to readers that it is wise to prepare for future disasters and plan to be self-sufficient for at least a week whether it is an earthquake, hurricane, or ice storm.

Here is a set of links for planning for a disaster.

Do it. Tomorrow.

"Was Vermont Warned?"

There are now two news stories (one yesterday, one today) complaining that Vermont was not warned of the danger of Irene. As I state below, my head was down in the data for days and so I cannot speak for anyone else. But, I can state that Vermont was included in the warnings Tweets that I was sending out.

How explicit were the warnings?

For four days, I — and others — were warning of the likelihood of flooding in New England. I posted this Saturday along with map outlining, in red, an area of “major flooding” that included Vermont.

Calling, in advance, for evacuation preparations for a 200-year flood plain width around rivers is indicative of an extreme hazard. I know the NWS had a flash flood watch out for the area. When I wrote about all of the hazards meteorologists were trying to think through, this was one of the hazards I was talking about.

So, as tragic and devastating as the record flooding has been, it is not accurate or fair to say there was “no warning.”

Here Comes Katia

The name “Katrina” is retired so Tropical Storm Katia has formed in the Atlantic.

She is expected to intensify into hurricane status the next few days. Important note: Don’t sweat Katia. It is by no means certain she will hit any land mass and, if she does, it will not be this week.

This is Worth a Separate Posting

For those that believe there was too much “hype” about Irene (I do not have an opinion, my head was deep in the data and I didn’t watch any coverage until landfall Sunday morning), consider these preliminary numbers from the New York Times. These statistics are from 1980 (when full-time high resolution satellite data was first becoming available) to present:

  • Damage?  First estimates are $14 billion; ranking 8th
  • Fatalities? Tied with Fran for 10th with 21, but Irene’s are expected to rise. UPDATE: According to the WSJ, 38 fatalities are now reported as of 10pm CDT Monday. As of 9am Tuesday, the death toll stands at 40. Irene is now #4 in terms of fatalities since 1980.
Average the two and you get the 9th 6th worst hurricane in 31 years.  
And, there is this when you are thinking about forecasts of hurricane intensity,
Imagine, for instance, if Irene had been about 20 percent stronger when it hit New York — that it had wind speeds of about 90 miles an hour instead of 75 miles an hour. That doesn’t sound like a huge difference and from a meteorological perspective, and it isn’t.
But from an economic perspective, that may have mattered quite a lot. Some of the scholarly literature suggests that the economic damage resulting from hurricanes is a function of wind speeds raised to the eighth power. I’ll spare you the math: what that means is that hurricane with wind speeds of 90 miles an hour might be as much a 4 or 5 times more destructive as one with wind speeds of 75 miles per hour. So if Irene had been just a bit stronger, we might be talking about economic losses on the order of $55 billion to $70 billion, rather than a “mere” $14 billion.
Because wind power (the wind’s destructive force) is not linear, the forecasts showing winds of 95 to 110 mph near the storm’s center (that we were forecasting would move inland farther west than shown in this computer model forecast) had the potential to cause major, major damage.

Given that Irene is already the 10th 4th worst in terms of fatalities at Cat. 1 intensity, those stronger winds would have threatened lives to a far greater extent. This was in the back of our minds as we were making those forecasts of Cat. 2 intensity on Thursday. 

Irene Recap: How Good Were the Forecasts?

So, how did the meteorological profession do with Irene, a rare hurricane that made landfall in the Northeast United States? Meteorologists almost always do postmortems on major storms because we need to learn from our mistakes so we can do it better next time.

By definition, it is difficult to forecast rare events because of the lack of analogues. For example, if there has never been a full-fledged hurricane in Manhattan in the era of skyscrapers, how will we know the level of damage a hurricane might cause?
So, with that in mind, let’s go over some of the forecasts made on this blog and compare them to reality. My colleagues at AccuWeather and I made some excellent proprietary forecasts that were sometimes ahead of those available from government sources, which is what our business clients pay for. However, because I do not post those forecasts on this blog, I’m doing an analysis of the public forecasts I posted here.
The early forecasts of Irene, made last Sunday (21st) were not very good. They took the storm toward Florida and had the intensity too low. On the other hand, the title of that posting was “Why We Can’t Get Too Confident on Hurricane Paths 5-Days (or Longer) Out.”
The first forecast in which I expressed confidence was titled, “This Looks Correct to Me: Irene’s Path.” I wrote, The eye (which is what is being forecast, not the geographic extent of the storm) could make landfall anywhere in the stippled area.
Arrow indicates the point of landfall as determined by the
National Hurricane Center.


The intensity was overforecast at this point. We were forecasting a category 3 and it was a cat 2 when it made landfall.

Tuesday at 7:19am (roughly four days before landfall), the point of landfall in North Carolina, while slightly far west, was extraordinarily good for four days out. There was still an over forecast by one category but that isn’t bad at all given it is four days out.

Why did the forecast improve? Because the National Weather Service started launching weather balloons at six-hour intervals and NWS and USAF hurricane hunter and high-level aircraft began gathering special data to load into the computer forecast models.

Shortly after 10pm, I forecast posted the first of a series of genuinely amazing path forecasts.

Things didn’t change much on Wednesday. I wouldn’t change very much of what I posted on Tuesday and Wednesday.

Thursday at noon I posted the two sets of forecasts I’m not proud of. Titled, This Looks Serious, and,  Irene: My Concern is Rising,  I walked readers through some of the newer computer models that were taking the intensity of Irene up to, perhaps, a category 4. If this had occurred, the results would have been devastating. Irene did intensify aloft but for scientifically unknown reasons the intensification never made it to the ground. Meteorologists just do not have a solid understanding of the processes which cause tropical systems to intensify or weaken.

Throughout the week, I warned of extensive power failures due to toppled trees from wind and wet ground. I posted the map below of forecast rainfall which I predicted would lead to “major flooding.”

Below is the rainfall map from Irene. Unfortunately, the colors are not the same but I believe you’ll agree that 3-4 days out (depending on location), the correlation between the forecast and actual is remarkable.

From this point on, the path, wind, and rainfall forecasts underwent little revision as confidence went up (i.e., the boundary of the “confidence interval” narrowed).

So, how would I rate the quality of the forecasts presented on this blog?

  • Path, 5 days to landfall and later:  A+
  • Intensity: C- 
  • Forecast of Widespread Power Failures: A
  • Forecast of “Major Flooding:” A+
  • Forecast of Window Breakage in Manhattan High-Rises: F
Please take a look at this posting and feel free to offer comments.  
Tropical depression Twelve may give us some problems next week. There are areas of disturbed weather from Florida to South America that bear watching. We are only about halfway through hurricane season. I suspect Irene will not be the only hurricane we will deal with this year. 
Thanks for reading.

ADDITION: Here is another take on the accuracy of the forecast. And, the New York Times has a good article about the weakening that took Irene from the 2 we forecast just southwest of NYC down to the borderline 1 it actually was.

Interactive map of Irene’s path and damage. Total “customers” (homes and businesses) that lost power are 5.8 million. The electric utility industry uses 3.5 people per “customer” so the total number of people without power is just over 20,000,000.

UPDATE 6:50PM: My friend, meteorologist Dr. Cliff Mass, has a completely different take. He does not believe Irene was even a hurricane north of the North Carolina border. As I understand NHC’s reasoning (and I may be incorrect), there were very high winds aloft and over water and they were concerned those would sustain the hurricane.

I present all of this because I want non-meteorologists to understand the complexities of what we are dealing with when it comes to hurricanes and tropical storms. 

Recap of Rain from Irene

This map is created by using a combination of rain gauges and radar estimates to fill in the gaps between gauges.

Combine these excessive rainfalls with what has already been a very wet August in the region and you have a recipe for extreme flooding.

Irene’s Aftermath

Here is a map of the amount of rain that has fallen with Irene, but it does not include rain that fell after 8am:

White = 20″ or more, purple = 15″ or more up to 8am EDT this morning.

A record stage is near Gilboa Dam and the town of Prattsville that “unimaginable” flooding is occurring. A reporter with Fox News is reportedly trapped along with the people in the area. More of this is going to occur the next few days.


The river is expected to break the record crest by three feet!


Flights are reportedly a mess. Here is my popular Airline Crisis Guide.

ADDITION at 6:30pm CDT. Power failures are affecting roughly 15,000,000 people. Restoration efforts are just now getting underway in the Carolinas but more are losing power in New England with the remains of Irene.

Tropical Storm Irene Now North of NYC

Irene made landfall at NYC and has been downgraded to a tropical storm. Now that she is over land she will weaken.

However, the risk of downed trees causing more power failures (3.5 million people without power and rising) and excessive rainfall causing major flooding remains.

The last tornado was allowed to expire. No tornado watches are out at present.