NHC increases hurricane forecast lead times

By: Dr. Jeff Masters , 7:27 PM GMT on January 05, 2010

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The National Hurricane Center (NHC) announced today that beginning with the 2010 hurricane season, their hurricane and tropical storm watches and warnings for the U.S. coast will be extended in time by an additional 12 hours. Warnings will now be issued 36 hours in advance instead of 24 hours, and watches will be issued 48 hours in advance, instead of 36 hours. The increase in lead time for watches and warnings has been made possible by the tremendous improvement in hurricane track forecasts, which have improved by over 50% in the past twenty years (Figure 1). "With increases in population and infrastructure along vulnerable U.S. coastlines, emergency managers need more lead time in order to make life-saving decisions regarding evacuations", said Bill Read, director of NOAA's National Hurricane Center, in today's press release.


Figure 1. Average track errors for NHC Atlantic tropical storm and hurricane forecasts issued between 1990 - 2008. Track errors have improved by over 50% in the past 20 years. Image credit: National Hurricane Center.

Commentary
NHC has been debating for a number of years how best to "invest" the gains accrued from the steady improvement in hurricane track forecasts. One obvious savings from these better hurricane forecasts has come from the reduced evacuation costs. When a hurricane warning is issued 24 hours before the expected arrival of hurricane-force winds at the coast, it costs approximately $1 million to evacuate each mile of U.S. coast warned (Aberson et al., 2006). This number will be higher for more densely populated areas of the coast, such as Miami, and may be a factor of six lower for the North Carolina coast (Whitehead, 2003). According to a 2007 presentation at the 61st Interdepartmental Hurricane Conference, the length of coast warned decreased significantly in the past decade. During the decade of the 1990s, the average length of a hurricane warning was 455 miles, but that fell to just 335 miles between 2000 - 2006. Thus, an average of 120 fewer miles of coast were warned, at an average savings of $120 million per hurricane warning issuance. During this period, 17 storms requiring 25 hurricane warnings occurred. If the costs of coastal evacuations are indeed $1 million per mile, the improved hurricane forecasts between 2000 - 2006 resulted in savings of $3 billion compared to what the forecasts of the 1990s would have cost.

However, the new increased lead times for hurricane watches and warnings will lead to an increase in the length of coast warned, due to the higher uncertainties in hurricane tracks at longer forecast lead times. Between 2004 - 2008, approximately 25% of the coast that was placed under a hurricane warning actually received hurricane force winds; this percentage was 20% for areas placed under a hurricane watch. These percentages will decline with the new increased watch and warning lead times, costing money in unnecessary evacuations, and leading to increased complacency in the warned population due to too much "crying wolf".

Balanced against these increased costs is the potential disastrous loss of life should a hurricane hit an unprepared, heavily populated shoreline. With the U.S. population continuing to increase rapidly in coastal regions, the time needed to evacuate vulnerable populated regions is increasing. For example, evacuation times for the major urban areas of Texas are 28 - 34 hours for a major hurricane. Though the costs of overwarning the coast is significant, the savings in both human lives and dollars from increased warning times should outweigh these costs. In the 2002 book, Hurricane: Coping With Disaster, Dr. Hugh Willoughby, former director of the Hurricane Research Division of NOAA's Atlantic Oceanographic and Marine Laboratory, analyzed hurricane death statistics. In 1950, about 70 U.S. residents died per year in hurricanes. In the 50 years since, the coastal population expanded by a factor of 3.2, so if we were managing the hurricane problem the way we did in 1950, we would be losing about 220 people a year. The long-term average is still about twenty per year, not including the deaths due to the levee failures during Katrina. That means we're preventing about 200 deaths per year compared with 1950. How much are these saved lives worth? A life, is, of course, priceless, but in the cold world of economics, the value of life-saving scientific research and government regulations is estimated using statistics of what people are willing to pay to avoid certain risks, and what extra money employers pay their workers to take on additional risks. This data comes primarily from payroll statistics, but opinion surveys also play a role. In 2004, the Environmental Protection Agency (EPA) valued an American life at $8 million. EPA cut the value of a life by 8% that year, and a further 3% in May 2008, making the economic value of a life $6.9 million in today's dollars. The Department of Transportation gives a lower figure of a life as being worth $5.8 million. Using this number implies a savings of about $1.2 billion per year for the 200 lives saved per year by better hurricane warnings and evacuations. Today's decision by NHC to increase warning times should continue this trend of saving lives, which will also provide considerable monetary benefit. Despite the increased costs and dangers of "crying wolf" too often due to overwarning the coast, I believe that the double value of saving lives--for both the intrinsic and monetary value of a human life--makes NHC's move of increasing warning and watch times the right call.

References
Whitehead, J.C., 2003: "One million dollars per mile? The opportunity costs of Hurricane evacuation", Ocean and Coastal Management 46, 1069.

I'll have a new post on Thursday or Friday.

Jeff Masters

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Quoting ElConando:


And then in 12 days cats and dogs will be living together!!!


Are we slightly being a butt head here...HUM..
Member Since: Posts: Comments:
holy sh**tola batman, looks like a hard freeze for daytona.

Daytona Beach (Ponce Inlet), FL, Daytona Beach, Florida (PWS)
Updated: 2 sec ago
32.9 °F
Clear
Windchill: 33 °F
Humidity: 74%
Dew Point: 26 °F
Wind: 3.0 mphfrom the WNW
Wind Gust: 4.0 mph
Pressure: 30.20 in (Rising)
Visibility: 10.0 miles
UV: 0 out of 16
Clouds: Clear -
(Above Ground Level)
Elevation: 12 ft

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537. jipmg
Quoting ElConando:


And then in 12 days cats and dogs will be living together!!!


actually my friend has cats and dogs living together so..
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Quoting Jeff9641:
Severe weather next week for Florida. Looks like we will go from snow to tornadoes in 6 days. WOW!!

http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/gfs/00/fp0_252.shtml


And then in 12 days cats and dogs will be living together!!!
Member Since: September 6, 2009 Posts: 2 Comments: 3710
ESL by LSU GOM IR Loop


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Quoting TampaSpin:


I still think you could see 1-2 inches in the Northern Parts of Florida!


We shall see man, we shall see!
Member Since: September 6, 2009 Posts: 2 Comments: 3710
Quoting jipmg:
http://cbs4.com/local/chill.weather.cold.2.1404048.html

State of emergency for florida


Your LINK***GOV'N CRIST DECLARES STATE OF EMERGENCY FOR FLORIDA**
Link
Member Since: August 25, 2009 Posts: 20 Comments: 6785
Quoting TampaSpin:


I still think you could see 1-2 inches in the Northern Parts of Florida!

that would b kewl if it does.. :)thanks tim
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Quoting FLPandhandleJG:
Hey tim.. You said that we the panhandle has a good chance of snow.. How much u think if none just a flurry or dusting.. ?


I still think you could see 1-2 inches in the Northern Parts of Florida!
Member Since: Posts: Comments:
All depends on the exact timing of precipitation for Tampa snow... If the current temp forecast stands, the bay area would go above freezing Saturday morning around 9am, so the front would have to be in the vicinity before then. All we can do is watch!
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Hey tim.. You said that we the panhandle has a good chance of snow.. How much u think if none just a flurry or dusting.. ?
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Quoting TampaSpin:
The 00Z Forecast comes out in about 45minutes....i would like to go to bed but, i need to see this forecast from models!


Tallahassee has no snow chance since it dropped Flurries Monday morning. Wonder what will come.
Member Since: September 6, 2009 Posts: 2 Comments: 3710
Quoting doabarrelroll:

My girlfriend is doing back flips with this news. Could you tell me how it is we will be getting snow. Are we looking at flurries? This is saturday!


Late FRiday nite/ Saturday morning early .....hard to say how much yet....Flurries for sure i think...possibly a nice dusting is possible.
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I would think half an inch of snow in any Florida city would cripple things.
Member Since: September 6, 2009 Posts: 2 Comments: 3710
The 00Z Forecast comes out in about 45minutes....i would like to go to bed but, i need to see this forecast from models!
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Quoting TampaSpin:


Yes i am more than 50% confident you will have some snow in Gator country.


Tampa gets snow before new orleans in 2010 haha wow!
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Quoting doabarrelroll:
Ok so very confused. I dont understand these charts. Is snow gonna happen here in Gainesville? Can someone help me understand these snow models


Yes i am more than 50% confident you will have some snow in Gator country.
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520. unf97
Good evening everyone.

The temperature is currently 26.8 degrees. It has dropped nearly 7 degress since 8 p.m. It certainly appears to be well underway to register the coldest temp reading of the season tomorrow morning.

Also, I checked the latest MOS Guidance projections and 16 degrees is being projected for Jax on Sunday morning low temp. The massive Arctic surge will be moving in big time this weekend, and that low temperature projection just may verify. One major factor if it gets that cold if we get any snow across areas in the Deep South later this week. Any additional snow pack will keep this extreme cold air mass from moderating, and certainly, we could see many record low temps shattered in many areas this weekend.

Tomorrow will be a big day analyzing the model runs with the GOM Low and the massive Arctic outbreak coming in behind this disturbance by the weekend.

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Quoting Bordonaro:


Kind of curious if there will be an Arctic outflow for Orca tonight?! I did tell Orca that I had hoped the Siberian Ridge gave him "a taste" of what most of Central Canada and the Eastern CONUS are experiencing!!


We need it for the pine beetle.. but only the interior of BC. We will save the snow for the Olympics.
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517. jipmg
http://cbs4.com/local/chill.weather.cold.2.1404048.html

State of emergency for florida
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Quoting KEEPEROFTHEGATE:
no not hard at all just need a nice arctic outflow for a couple of hrs the area can have extremes it can be 45 now and 25 by morning


Kind of curious if there will be an Arctic outflow for Orca tonight?! I did tell Orca that I had hoped the Siberian Ridge gave him "a taste" of what most of Central Canada and the Eastern CONUS are experiencing!!
Member Since: August 25, 2009 Posts: 20 Comments: 6785
Quoting RTLSNK:
499 - Orcasystems

I saw that Orca, you thought I had gone to bed already didn't you. :)

28*F in Macon right now headed down to 18*F with a 10*F wind chill . I am not a happy camper.

Just remember, I have friends:


Brrrrr to cold for me


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Most of my family in cleveland wants the snow to stop, i was like send sum of that down here.. There like, we will switch u winters.. Then i said, Naw... Im good
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This better not happen as it appears currently or we will be looking at a lot of snow in the northern part of Florida.....





YOu can find this stuff at my web site if you need here: TampaSpin
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499 - Orcasystems

I saw that Orca, you thought I had gone to bed already didn't you. :)

28*F in Macon right now headed down to 18*F with a 10*F wind chill. I am not a happy camper.

Just remember, I have friends:
Member Since: Posts: Comments:
Quoting Bordonaro:


Hopefully not too much of the Arctic air spills over! IF it does, it's NOT in your forecast (wouldn't be a big surprise), it's gonna get a "wee bit nippy"!! NWS Seattle, WA has NO mention of cooler temps, either. It must be hard to forecast the Arctic air over the Canadian Rockies, no sarcasm intended!
no not hard at all just need a nice arctic outflow for a couple of hrs the area can have extremes it can be 45 now and 25 by morning
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Quoting tornadodude:
goodnight all! (:


Turning in, sleep well. I am sure you'll be dreaming of your "late White Christmas", then waking up knowing it's really coming!!
Member Since: August 25, 2009 Posts: 20 Comments: 6785
Quoting TampaSpin:


Orca your having way to much fun with your dance with this....LOL


Ummmmm I am just practising colours :)
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goodnight all! (:
Member Since: June 28, 2006 Posts: 24 Comments: 8201
Nippy Ft Worth-Dallas NWS Forecast Discussion Snippet from 3:45PM CST today. Notice the comment on the computer models:

OF GREATER CONCERN WILL BE THE EXTRAORDINARY COLD...WHICH IS
UNMATCHED IN THE LAST DECADE. MOST OF NORTH TEXAS WILL REMAIN IN
THE 20S DURING THE DAYLIGHT HOURS THURSDAY WITH WIND CHILLS IN THE
SINGLE DIGITS AND TEENS. THE WIND WILL DIMINISH BUT NOT SUBSIDE
THURSDAY NIGHT...RESULTING IN WIND CHILLS NEAR OR BELOW ZERO...
MAINLY NORTH OF THE I-20 CORRIDOR. LOW TEMPERATURES FRIDAY AND
SATURDAY MORNING WILL BE IN THE TEENS REGIONWIDE. WITH CLEAR SKIES
AND DIMINISHING WINDS FRIDAY NIGHT...SOME AIR TEMPERATURES IN THE
SINGLE DIGITS WILL BE POSSIBLE IN WESTERN AND NORTHERN ZONES...
PARTICULARLY IF SFC RIDGE IS WITHIN FWD CWA.

MODERATING WILL BEGIN ON SATURDAY...BUT TEMPERATURES WILL REMAIN
BELOW NORMAL INTO NEXT WEEK. ARCTIC INTRUSION HAS SENT SYNOPTIC
MODELS IN DIFFERENT DIRECTIONS. WITH LITTLE CONTINUITY NEXT
WEEK...NO SIGNIFICANT CHANGES HAVE BEEN MADE TO EXTENDED FORECAST.
Member Since: August 25, 2009 Posts: 20 Comments: 6785
Not going to get any warmer anytime soon.

Lake City, Florida

Saturday Night through Sunday Night
Mostly clear. Lows around 19. Highs around 50.
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Quoting tiggeriffic:
KEEPER! I thought they'd have locked you back behind the gate after hurricane season ended...lol...glad to see you still roaming!
roaming i be hello tigger good to see ya
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Quoting TampaFLUSA:
Holy Crap Jeff might be right, Channel 28 Tampa said that sleet might fall here.


Link below to the Tampa Weather Forecast update, The Met mentions sleet possible in portions of Florida. He did NOT say where in Florida, however :o)

Link
Member Since: August 25, 2009 Posts: 20 Comments: 6785
503. jipmg
Quoting Jeff9641:

http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/gfs/00/fp0_108.shtml


That model brings the snow line down into SFL..
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Quoting Orcasystems:
Macon GA


Thursday
Partly sunny with a 30 percent chance of rain or snow
Thursday Night
Mostly cloudy with a 40 percent chance of snow


Orca your having way to much fun with your dance with this....LOL
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Anybody see a video clip of a "journalist" in fur-lined (faux, I hope) hooded heavy ski jacket telling folks in bathing suits on beach in sunny Florida that it was cold? Very funny...on our 9 news CBS affiliate. (I know, run-on sentence.) Have no idea where it originated, but hope it's on 9NewsNow website tomorrow.
Member Since: August 19, 2008 Posts: 32 Comments: 1918
Macon GA


Thursday
Partly sunny with a 30 percent chance of rain or snow in the afternoon. Highs in the upper 40s. West winds 5 to 15 mph.

Thursday Night
Mostly cloudy with a 40 percent chance of snow or rain in the evening...then partly cloudy after midnight. Windy. Lows in the lower 20s. West winds 10 to 20 mph.
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DESTIN FL


Thursday Night
Breezy. Mostly cloudy. Numerous rain showers in the evening. Chance of snow through the night. Chance of rain after midnight. Lows 23 to 28. North winds 15 to 25 mph becoming 10 to 20 mph after midnight. Gusts up to 40 mph. Chance of rain 60 percent.
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Holy Crap Jeff might be right, Channel 28 Tampa said that sleet might fall here.
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Quoting Jeff9641:


Thanks I was having a hard time getting my link up. Sorry for the triple post.


happens to the best of us (;
Member Since: June 28, 2006 Posts: 24 Comments: 8201
local met. Dennis Phillips just said some rain mixed in with sleet for Sat. morning.
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Wow...just wow forecast lows for Tallahassee Sat night 12 degrees w/ a feels like of 1. Talk about bitter, nasty, and frigid by Florida Standards
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491. jipmg
They just asked david brenard of cbs4, if it could snow in south florida, he said as of right now no, but there is rain forecasted for sunday morning, the morning temperature is expected to be around 37..
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Quoting Jeff9641:
http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/gfs/00/fp0_108.shtml


I think the Northern part of Florida could easily see a good bit of snow. From Tallahassee Northward
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.