Which Hurricane Forecast Model Should You Trust?

By: Dr. Jeff Masters , 1:05 PM GMT on August 07, 2013

The National Hurricane Center (NHC) set a new record in 2012 for accuracy of their 1, 2, 3, and 4-day Atlantic tropical cyclone track forecasts, but had almost no skill making intensity forecasts, according to the 2012 National Hurricane Center Forecast Verification Report, issued in March 2013. The new records for track accuracy were set despite the fact that the season’s storms were harder than average to forecast. The average error in a 1-day forecast was 46 miles, and was 79 miles for 2 days, 116 miles for 3 days, 164 miles for 4 days, and 224 miles for 5 days. The official track forecast had a westward bias of 10 - 17 miles for 1 - 3 day forecasts (i.e., the official forecast tended to fall to the west of the verifying position), and was 38 and 75 miles too far to the northeast for the 4- and 5-day forecasts, respectively.


Figure 1. Verification of official NHC hurricane track forecasts for the Atlantic, 1990 - 2012. Over the past 15 - 20 years, 1 - 3 day track forecast errors have been reduced by about 60%. Track forecast error reductions of about 50% have occurred over the past ten years for 4- and 5-day forecasts. Image credit: 2012 National Hurricane Center Forecast Verification Report.

NHC Intensity Forecasts: Little Improvement Since 1990
Official NHC intensity forecasts did better than usual in 2012, and had errors lower than the 5-year average error for 1, 2, 3, 4, and 5-day forecasts. However, 2012's storms were easier to predict than usual, due to due to a lack of rapidly intensifying hurricanes. These rapid intensifiers are typically the source of the largest forecast errors. The skill of official NHC 24-hour intensity forecasts made in 2012 for the Atlantic basin were only about 15% better than a "no-skill" forecast; 2, 3, 4, and 5-day intensity forecasts had no skill.


Figure 2. Verification of official NHC hurricane intensity forecasts for the Atlantic, 1990 - 2012. Intensity forecasts have shown little to no improvement since 1990. Image credit: 2012 National Hurricane Center Forecast Verification Report.

Which Track Model Should You Trust?
As usual, in 2012 the official NHC forecast for Atlantic storms was almost as good as or better than any individual computer models--though NOAA's GFS model did slightly better than the NHC official forecast at 12, 24, and 48-hour periods, and the European model forecast was slightly better at 12-hour forecasts. Despite all the attention given to how the European Center (ECMWF) model outperformed the GFS model for Hurricane Sandy's track at long ranges, the GFS model actually outperformed the European model in 2012 when summing up all track forecasts made for all Atlantic named storms. This occurred, in part, because the European model made a few disastrously bad forecasts for Tropical Storm Debby when it was in the Gulf of Mexico and steering currents were weak. For several runs, the model predicted a Texas landfall, but Debby ended up moving east-northeast to make a Northwest Florida landfall, like the GFS model had predicted. However, the best-performing model averaged over the past three years has been the European Center model, with the GFS model a close second. Wunderground provides a web page with computer model forecasts for many of the best-performing track models used to predict hurricane tracks. The European Center does not permit public display of tropical storm positions from their hurricane tracking module of their model, so we are unable to put ECMWF forecasts on this page. Here are some of the better models NHC regularly looks at:

ECMWF: The European Center's global forecast model
GFS: NOAA's global forecast model
NOGAPS: The Navy's global forecast model (now defunct, replaced by the NAVGEM model in 2013)
UKMET: The United Kingdom Met Office's global forecast model
GFDL: The Geophysical Fluid Dynamics Laboratory's hurricane model, initialized using GFS data
HWRF: The intended successor for the the GFDL hurricane model, also initialized using GFS data
CMC: The Canadian GEM model
BAMM: The very old Beta and Advection Model (Medium layer), which is still useful at longer ranges

If one averages together the track forecasts from the first six of these models, the NHC official forecast will rarely depart much from it. As seen in Figure 3, the HWRF and UKMET were well behind the ECMWF and GFS in forecast accuracy in 2012, but were still respectable. The simple BAMM model did well at 3, 4, and 5-day forecasts. The GFDL and CMC models did quite poorly compared to the ECMWF, GFS, UKMET, and HWRF. The Navy's NOGAPS model also did poorly in 2012, and has been retired. Its replacement for 2013 is called the NAVGEM model.


Figure 3. Skill of computer model forecasts of Atlantic named storms in 2012, compared to a "no skill" model called "CLIPER5" that uses just climatology and persistence to make a hurricane track forecast (persistence means that a storm will tend to keep going in the direction it's current going.) OFCL=Official NHC forecast; GFS=Global Forecast System model; GFDL=Geophysical Fluid Dynamic Laboratory model; HWRF=Hurricane Weather Research Forecasting model; UKMET=United Kingdom Met Office model; ECMWF=European Center for Medium Range Weather Forecasting model; TVCA=one of the consensus models that lends together several of the above models; CMC=Canadian Meteorological Center (GEM) model; BAMM=Beta Advection Model (Medium depth.) Image credit: National Hurricane Center 2012 verification report.

Which Intensity Model Should You Trust?
Don't trust any of them. NHC has two main statistical intensity models, LGEM and DSHP (the SHIPS model with inland decay of a storm factored in.) In addition, four dynamical models that are also use to track hurricanes--the GFS, ECMWF, HWRF, and GFDL models--all offer intensity forecasts. With the exception of the GFS model, which had a skill just 5% better than a "no-skill" intensity forecast for predictions going out 36 hours, all of these models had no skill in their intensity forecasts during 2012. The ECMWF and HWRF models were the worst models for intensity forecasts of 3, 4, and 5 days, with a skill of 20% - 60% lower than a "no-skill" forecast. The LGEM model, which was a decent intensity model in 2011, tanked badly in 2012 and had near-zero skill. The only model that was any good in 2012 was the IVCN "consensus" model, which averages together the intensity forecasts of two or more of the intensity models such as LGEM, GFDL, HWRF, and DSHP.

Some Promising Models From the Hurricane Forecast Improvement Project (HFIP)
Last year was the fourth year of a ten-year project, called the Hurricane Forecast Improvement Project (HFIP), aimed at reducing hurricane track and intensity errors by 50%. The new experimental models from HFIP generally performed poorly in 2012. However, the new FIM9 15-km global model was competitive with the ECMWF and GFS models for track, and the new CIRA Statistical Intensity Consensus (SPC3) model for intensity performed better than many of the traditional intensity models.

For those interested in learning more about the hurricane forecast models, NOAA has a 1-hour training video (updated for 2011.) Additional information about the guidance models used at the NHC can be found at NHC and the NOAA/HRD Hurricane FAQ.

Sources of Model Data
You can view 7-day ECMWF and 16-day GFS forecasts on wunderground's wundermap with the model layer turned on.
Longer ten-day ECMWF forecasts are available from the ECMWF web site.
FSU's experimental hurricane forecast page (CMC, ECMWF, GFDL, GFS, HWRF, and NAVGEM models)
NOAA's HFIP model comparison page (GFS, ECMWF, FIM, FIM9, UKMET, and CMC models.)
Experimental HFIP models

Quiet in the Atlantic
There are no tropical cyclone threat areas in the Atlantic to discuss today, and none of the reliable models for tropical cyclone formation is predicting development during the coming seven days. I plan on having a detailed update on Friday to discuss the latest long-range forecasts for the coming peak part of hurricane season.

Jeff Masters


The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 1986 - 1936

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40Blog Index

I'm kinda trying to avoid a big argument in the newer feeds as the issue surrounding Camille evokes some pretty intense emotion in people. I posted here because this is the entry where those comments were made.

Also, I am not too familiar with the commenting format of Dr. Master's blog.
Member Since: Posts: Comments:
@ExtremePlanet

Why post that here on Dr. M's old blog? Would be much better to post it on the current blog, I would think. I for one respect your opinion and value it, I can't imagine all those 200 mph readings as being true...
Member Since: Posts: Comments:
I know the discussion on Hurricane Camille is ancient history but I can't help comment since I was described as "an idiot" who "wants money" and is "ignoring the experts" and "disrespecting the victims of the storm" due to my blog entry "Hurricane Camille was not a Category 5 at Landfall."

Just to clarify, all the information I used was from official sources (linked in my post directly). The official NOAA wind contour map of the storm shows winds at landfall being 145mph. A thorough survey by the National Bureau of Standards (the government/civil defense) in 1969 estimated peak winds at landfall to be 125mph. Another extensive survey of the Mississippi coast found little wind damage but tremendous storm surge damage. Additionally, all the claims that gusts of "212", "218" or higher were recorded are inaccurate as no source anywhere mentions such readings. The highest on land reading was 129mph, and the highest offshore reading (70 miles from MS) was 172mph, which was reduced to 144mph at 30ft elevation by the NBS. The anemometer also did not fail due to the storm but instead a jam in the paper tray.

Finally, it is not "disrespectful" to seek accuracy on historical events. The NWS re-analysis commission is not disrespecting those who were lost in historical storms, only finding the truth so we can better prepare for future events. Camille was a catastrophic storm no matter what the winds at landfall were.

And just to clarify, I pay for my website domain and have never received a penny from advertising.

Anyways, carry on...
Member Since: Posts: Comments:
Once something starts taking shape the data input for the models becomes more reliable to forecast initial track of system. We have nothing yet but during the next few weeks when favorable conditions take over atlantic basin the models will start making more sense.
Member Since: Posts: Comments:
Anything that forms in the GOM next week will be pulled north by the strong trough pushing east. So the northern gulf coast states from Louisinana to the Florida panhandle should be in alert. Depending on the timing of these two systems interacting with eachother the west coast of Florida could be impacted directly as well.
Member Since: Posts: Comments:
In a cat. 1 hurricane you can expect sustained winds of 74-95mph with 100mph plus gusts around the eyewall of the storm. Winds will shift direction as the hurricane passes. If you get the eye you will experience calm wind conditions. But after that is the back side winds in opposite direction from first half and usually the backside is worse than the first half. I have lived through hurricanes Irene 1999 ,Frances 2004,Jeanne 2004 and Wilma 2005 eye of this one went over my location got the worst of this one in West Palm Beach. The other made landfall 40 miles north of my location but since hurricane are so large we got the southern quadrants of Frances and Jeanne and experienced cat 1 hurricane conditions. But Frances forward speed was so slow we were pounded for over 24 hrs in hurricane conditions.
Member Since: Posts: Comments:
Member Since: December 31, 1969 Posts: Comments:
Good evening everyone...looks like the latest GFS has the BOC.

Member Since: December 31, 1969 Posts: Comments:
Quoting 1970. weatherlover94:


according to the NHC new numbers when it does become active it is going to STAY active
I knew they would keep it the same , or very near the same ! They know something we don't !
Member Since: December 31, 1969 Posts: Comments:
Welcome Margie , Good to have you aboard , it's not always this hostile , usually very civil!
Member Since: December 31, 1969 Posts: Comments:
1976. ncstorm
Member Since: Posts: Comments:
1975. WunderAlertBot (Admin)
JeffMasters has created a new entry.
Quoting 1927. Patrap:


man, look at that shear.. howdy Pat!
Member Since: Posts: Comments:
Quoting 1917. mikatnight:


Even the news too? I noticed the piece you posted on your FB page from ch25 pretty much ignored it (the real problem). It's going to require a political solution?


Bingo, that is the "only" answer. The sad truth is our elected officials are PAYING them to do this, then they make US foot the bill for pumps, plumbing and cleaning up their pollution. Then, when we the citizens try redress in Court over illegal 30 year leases on OUR property, the State Legislature ratifies the action. In Court, we had to fight the US Justice Depart.. so, our Government protects them in Court too...

The Ballot Box is the answer. It can fix what ails us.
Member Since: Posts: Comments:
Quoting 1891. JLPR2:
No wonder the 12z developed it, look at what the 18z run shows...



Simply massive area of convection emerging from Africa.
On schedule.
Member Since: Posts: Comments:
Quoting 1967. Doppler22:

Can you imagine how those waves would turn out if the Tropical Atlantic was prime for development?


according to the NHC new numbers when it does become active it is going to STAY active
Member Since: Posts: Comments:
Hurricane Charely - wait until the 52 sec mark and check out the wind speeds.
http://www.youtube.com/watch?v=UeM-cjTEEA8
Member Since: Posts: Comments:
Quoting 1966. islander101010:
next.cv.wave....the.big.one


Not holding my breath but we shall see
Member Since: Posts: Comments:
Quoting 1946. Grothar:
Those waves look good until they get into the Atlantic




Can you imagine how those waves would turn out if the Tropical Atlantic was prime for development?
Member Since: Posts: Comments:
next.cv.wave....the.big.one
Member Since: Posts: Comments:
Quoting 1955. Sfloridacat5:


Pray you don't have a cat 5 go through your neighborhood. Extensive stuctural wind damage from Hurricane Andrew (gusts of 180 mph).

My late grandfather lived in that complex (Pinewood Villas), but passed away in 1992 before Andrew. He lived in one of the units on the end. Though Andrew happened less than a year before I was born, I watched a home video recently of my family visiting my grandfather out at Pinewood Villas, and it was kind of eerie watching it knowing what was going to happen to that complex and all those beautiful pine trees about a year later..
Member Since: Posts: Comments:
Quoting 1929. Socalmargie:
in california we have santa anna winds which can reach 80mph and above, but very dry. is that what i can expect in a hurricane i just moved to the east coast


Hi Margie,

As someone who's lived on both coasts, but never been in the strongest winds of a hurricane, I'd say the biggest difference is water. In the many tropical storms I went through, the wind was always strongest in the midst of a downpour(spiral bands). In a hurricane, it rains for hours before the strongest winds even arrive, so you have waterlogged soil and a much greater risk of downed trees/powerlines.

Welcome to the blog :)
Member Since: Posts: Comments:
Quoting 1912. PalmBeachWeather:
I see Indian River Guy "Marty" is watching....Thanks friend for all you do


Just got off the water. Deployed some reef balls at Pecks Lake for shore protect. Cooperative effort put together for an Eagle Scout service requirement. State Parks, Florida Oceanographic Society, Indian Riverkeeper, and Reilly, our Scout. I did not attend the SFWMD WRAC meeting some of you will hear about, I did something constructive :)

Thank you for your support, come join us on Sunday, we want to have continuous hands from Stuart Beach to Jensen Beach. Last Saturday 7000 showed...

ohh, my last post number was 1909, Gro will understand this, maybe some others.. SVDB... always wanted one...
Member Since: Posts: Comments:
Quoting 1951. opal92nwf:

Well there's somebody probably answering your question right now, but:

In a hurricane, one thing that can be different with the winds is that they are more turbulent and erratic. Such that there can be much higher gusts at different times. Also, the wind will most likely change directions as the storm moves over the area, resulting in more potential damage than straight line winds in an arid area.

Also, (as you probably already noticed) there is an abundance of large broadleaf and other thick-canopied trees in the Eastern U.S. not seen in California. This makes the wind seem a lot more destructive when many of these trees fall down and as the winds whip through them.

And then of course, in a Category 2+ storm, you will find winds higher than any Santa Ana winds out in California.



That's a good summary, Opal, for someone who's never been in one. The only thing I would add would be to get together a hurricane preparedness kit.
Member Since: Posts: Comments:
What the heck happened to the 18z GFS? It keeps the low over the Cape Verde islands without moving a single mile from 204 hours to 360 hours, while moving the isobars out from under it and getting defused into another wave. Seems like a contaminated run to me.
Member Since: Posts: Comments:
Quoting 1954. wunderweatherman123:
18z GFS is weird. doesnt develop anything and keeps everything weak...


18Z is very unreliable
Member Since: Posts: Comments:
Quoting 1793. Patrap:


That ULL gives me the heebie-jeebies! Especially watching it roll towards the west and GOM. Just don't like seeing any swirling mass heading towards GOM or round the Isles or FL LOL
Member Since: Posts: Comments:
Quoting 1946. Grothar:
Those waves look good until they get into the Atlantic



Quoting 1946. Grothar:
Those waves look good until they get into the Atlantic





Hi Gro-

But it seems that the ITCZ is moistening up and sooner or later you know what will happen- your cactus will get appropriately watered.
Member Since: Posts: Comments:
Quoting 1948. SuperStorm093:
Is there any MOD that is on right now, thank you.



Will you plzs this use your ignore tool and this add him too your ignore list
Member Since: December 31, 1969 Posts: Comments:
That wave coming off the coast of Africa is HUGE guys
Member Since: Posts: Comments:
Quoting 1929. Socalmargie:
in california we have santa anna winds which can reach 80mph and above, but very dry. is that what i can expect in a hurricane i just moved to the east coast


Pray you don't have a cat 5 go through your neighborhood. Extensive stuctural wind damage from Hurricane Andrew (gusts of 180 mph).


Damage path Hurricane Charley (cat 4 winds gust 145 )
Member Since: Posts: Comments:
18z GFS is weird. doesnt develop anything and keeps everything weak...
Member Since: Posts: Comments:
Quoting 1947. mikatnight:


I don't think he meant it in a bad way.
Rules are Rules, and I took that in the bad way, he needs to get banned temporarily, I did nothing wrong and he came at me.
Member Since: Posts: Comments:
Quoting 1916. Camille33:
Big hurricane coming to north gulf coast next week this not looking good !!


What makes you think so ?
Member Since: Posts: Comments:
Quoting 1929. Socalmargie:
in california we have santa anna winds which can reach 80mph and above, but very dry. is that what i can expect in a hurricane i just moved to the east coast

Well there's somebody probably answering your question right now, but:

In a hurricane, one thing that can be different with the winds is that they are more turbulent and erratic. Such that there can be much higher gusts at different times. Also, the wind will most likely change directions as the storm moves over the area, resulting in more potential damage than straight line winds in an arid area.

Also, (as you probably already noticed) there is an abundance of large broadleaf and other thick-canopied trees in the Eastern U.S. not seen in California. This makes the wind seem a lot more destructive when many of these trees fall down and as the winds whip through them.

And then of course, in a Category 2 storm and higher, you will find winds higher than any Santa Ana winds out in California.

Well that's my 2 cents..
Member Since: Posts: Comments:
Quoting 1901. MAweatherboy1:
If you're looking for something good to track for the next few days, keep an eye on 11W in the West-Pac. It's outflow pattern is excellent for such a young system:



And it is already building a solid core:



With favorable conditions in its path RI is a pretty good possibility, as JTWC has said. They forecast a powerful 120kt peak intensity through 5 days. If this path were to verify it would have a high end Cat 3 equivalent passing over the far northern Philippines within 3-4 days and a Cat 4 bearing down on Hong Kong in 5-6 days:

Definitely going to be interesting to track. This is the typhoon the GFS has been developing for days.
Member Since: Posts: Comments:
Is there any MOD that is on right now, thank you.
Member Since: Posts: Comments:
Quoting 1940. SuperStorm093:
Can a MOD please ban Camille, I have the quote he made, and he just changed it thank you, I just stated my opinion, and he went off. Thank you.

Called me a smuck


I don't think he meant it in a bad way.
Member Since: December 31, 1969 Posts: Comments:
1946. Grothar
Those waves look good until they get into the Atlantic



Member Since: Posts: Comments:
Quoting 1929. Socalmargie:
in california we have santa anna winds which can reach 80mph and above, but very dry. is that what i can expect in a hurricane i just moved to the east coast


Winds can reach much higher velocities, and definietly are NOT dry.


Member Since: Posts: Comments:
If someone is going to call you names, the least they can do is spell it correctly. Schmuck or shmuck ;-)


Quoting SuperStorm093:
Can a MOD please ban Camille, I have the quote he made, and he just changed it thank you, I just stated my opinion, and he went off. Thank you.

Called me a smuck
Member Since: Posts: Comments:
Quoting 1940. SuperStorm093:
Can a MOD please ban Camille, I have the quote he made, and he just changed it thank you, I just stated my opinion, and he went off. Thank you.

who goes off 1 run like you! you need to look where the weakness is and learn from me!!
Member Since: Posts: Comments:
Can a MOD please ban Camille, I have the quote he made, and he just changed it thank you, I just stated my opinion, and he went off. Thank you.

Called me a smuck
Member Since: Posts: Comments:
Quoting 1935. Socalmargie:
wow! kind of a hostile blog i see :(


Welcome, Margie. I'm relatively new myself. Blog is usually pretty civil, so don't let that discourage you. What part of the E. Coast?
Member Since: Posts: Comments:

weakness over florida here!!! who cares about the gfs this storm is going to go north here and not where it go so i just cancel this model run!!!!!!
Member Since: Posts: Comments:
A hurricane on the Gulf Coast eh? Well, I just pruned my citrus trees so they should be good!
Member Since: Posts: Comments:
Quoting 1919. Socalmargie:
Am i allowed to ask a weather question?


What I do, scare you off? I was only kidding. Answers here only cost about 25 cents each.

Correct answers are rather pricy though.
Member Since: December 31, 1969 Posts: Comments:

Viewing: 1986 - 1936

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40Blog Index

Top of Page

Category 6™

About

Cat 6 lead authors: WU cofounder Dr. Jeff Masters (right), who flew w/NOAA Hurricane Hunters 1986-1990, & WU meteorologist Bob Henson, @bhensonweather