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: 36 - 1

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 | 40 — Blog Index

Enjoyed learning about the models. Thanks Dr. M!!
Member Since: Posts: Comments:
Quoting 24. SouthernIllinois:

Exactly what I was looking for. Thanks so much! :P
You're welcome. :) Here is a look at the lower resolution FIM-7 which goes out to the longer ranges.



And continues to show a Tropical Storm in the GOM.

Member Since: December 31, 1969 Posts: Comments:
Blog hiccup!
Member Since: Posts: Comments:
Quoting 29. 69Viking:


Taco where you located?

Mobile Alabama not to far from you I think :o)

Taco :o)
Member Since: Posts: Comments:
Quoting 13. java162:



tropical wave producing some pretty wet weather in dominica........


And nothing for us as usual.
Member Since: December 31, 1969 Posts: Comments:
What's all this racket going on?
Member Since: Posts: Comments:

13Z Day 1 Probabilistic Tornado (click for full outlook discussion and graphics)

DAY 1 CONVECTIVE OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK
0757 AM CDT WED AUG 07 2013

VALID 071300Z - 081200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN AND
CNTRL PLAINS...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN GREAT
LAKES AND UPPER OH VALLEY...

...SRN AND CNTRL PLAINS...
AN UPPER-LEVEL TROUGH IS FORECAST TO MOVE INTO THE SRN ROCKIES TODAY
AS SEVERAL IMPULSES MOVE ENEWD INTO THE SRN AND CNTRL PLAINS. AT THE
SFC...A LOW WILL DEEPEN ACROSS NORTHWEST TX AS SFC WINDS BECOME
BACKED ACROSS THE TX PANHANDLE...SW KS AND NW OK.
SFC DEWPOINTS IN
THE LOWER TO MID 60S F SHOULD ALLOW FOR MODERATE DESTABILIZATION
ACROSS MUCH OF THE SRN AND CNTRL PLAINS THIS AFTERNOON. IN
RESPONSE...SCATTERED TO NUMEROUS THUNDERSTORMS SHOULD INITIATE FROM
SERN CO EWD ACROSS SRN KS DURING THE MID AFTERNOON WITH CONVECTION
EXPANDING IN COVERAGE AND MOVING SEWD ACROSS THE SLIGHT RISK AREA.

FORECAST SOUNDINGS AT PERRYTON TX AND GAGE OK AT 00Z/THU SHOW MLCAPE
IN THE 1500 TO 2000 J/KG RANGE WITH AROUND 45 KT OF 0-6 KM SHEAR.

THIS ENVIRONMENT SHOULD BE FAVORABLE FOR SUPERCELLS LATE THIS
AFTERNOON ESPECIALLY IF CELLS CAN REMAIN DISCRETE. AN ISOLATED
TORNADO THREAT COULD DEVELOP FROM THE ERN OK PANHANDLE SWD ACROSS
THE ERN TX PANHANDLE AND WRN OK WHERE SFC WINDS SHOULD BE SELY
HELPING TO ENHANCE LOW-LEVEL SHEAR.
AN ELEVATED MIXED LAYER SHOULD
EXTEND EWD FROM THE HIGHER TERRAIN OF NE NM EWD ACROSS THE SRN
PLAINS WHICH SHOULD HELP LARGE HAIL PRODUCTION. STORM COVERAGE IS
FORECAST TO EXPAND MARKEDLY IN THE EARLY EVENING AS AN MCS ORGANIZES
AND MOVES SEWD INTO NW AND CNTRL OK WHERE WIND DAMAGE AND HAIL WILL
BE POSSIBLE. THE WIND DAMAGE THREAT COULD BECOME ENHANCED IF A
BOWING MCS CAN DEVELOP AS SEVERAL MODELS SUGGEST...
Member Since: Posts: Comments:
Quoting 2540. taco2me61:

That will be the one that will be on top of us later today and evening :o(

Taco :o)


Taco where you located?
Member Since: Posts: Comments:
Thanks for the update Doc, off to read it now, looks like a good topic!
Member Since: Posts: Comments:
192 hours
Member Since: Posts: Comments:
Quoting 23. mikatnight:
Good Morning!

7:25 am (11:25 GMT)

Looking east on Ocean Avenue towards the new bridge (still under construction) in Lantana, Florida.

No rain here for the first time in 6 days, but I see it keeps on raining in Broward County. Talk about leaving the water running, somebody better call a plumber!



Dexter's Weather Report for Wednesday, August 7th...

Dex would also like to take this time to remind everyone to make sure they're prepared for the expected upcoming spike in tropical cyclone activity, and that Palm Beach County residents in particular should download the smartphone app, 'PBC DART' (iTunes or Android).
And in case you missed it the first 20 times...

HURRICANE PROTOCOL



HURRICANE AWARENESS


Hurricane Preparedness - Wunderground

Tropical Cyclone Preparedness Guide - NHC (pdf)

Hurricane Preparedness 2013 - Palm Beach County

Storm 2013 - PB Post
What type of breed is dexter?
Member Since: Posts: Comments:
here is something at 24 hours from now
Member Since: Posts: Comments:
Good Morning!

7:25 am (11:25 GMT)

Looking east on Ocean Avenue towards the new bridge (still under construction) in Lantana, Florida.

No rain here for the first time in 6 days, but I see it keeps on raining in Broward County. Talk about leaving the water running, somebody better call a plumber!



Dexter's Weather Report for Wednesday, August 7th...

Dex would also like to take this time to remind everyone to make sure they're prepared for the expected upcoming spike in tropical cyclone activity, and that Palm Beach County residents in particular should download the smartphone app, 'PBC DART' (iTunes or Android).
And in case you missed it the first 20 times...

HURRICANE PROTOCOL



HURRICANE AWARENESS


Hurricane Preparedness - Wunderground

Tropical Cyclone Preparedness Guide - NHC (pdf)

Hurricane Preparedness 2013 - Palm Beach County

Storm 2013 - PB Post
Member Since: Posts: Comments:
Outstanding synopsis of the relevant topic of discussion Dr.

These rapid intensifiers are typically the source of the largest forecast errors.


Impossible to predict a rapid intensification event based on a sudden drop in sheer or real time warm pool event from the standpoint of the intensity models 24 hours or more out.

However, as suggested by some of research from FSU, lightening intensification in the eye wall typically can result in a rapid intensification event, in the 2-5 hour time frame, based upon the storms they looked at(which I believe included Hurricane Katrina in the Gulf when she ramped up to Cat 4 or 5 at one point). Reason why on-site doppler radar (in the tail of the Orions)is a great tool as well as the real-time lightening satellite data.

At least, NHC can issue real time advisories, or special advisories, upping the Cat and warnings as each storm dictates.
Member Since: Posts: Comments:
Quoting 12. SouthernIllinois:

You post the FIM quite a bit, Caleb. How does it do with precipitation? And would it show accumulated amounts for me down here for the next 4 days? Does it have that capability?? TIA.
Yes, indeed it does.

Looks like anywhere from 3-5 inches in your area for the next 7 days.

Member Since: December 31, 1969 Posts: Comments:
Quoting 18. hurricanes2018:
Quiet in the Atlantic on august 7 2013
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.


maybe no storm this august!

I doubt it, if 2009 had some storms 2013 will in August. Go back and read Dr.M's entry for 8/07/09 and then read the day after.
Member Since: Posts: Comments:
Quiet in the Atlantic on august 7 2013
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.


maybe no storm this august!
Member Since: Posts: Comments:
Quoting 11. SouthernIllinois:
More heavy showers and thunderstorms developing in Missouri expected to move eastward into Southern Illinois through the morning.



Got a tiny bit of rain heading your way. GET TO HIGHER GROUND....LOL
Member Since: Posts: Comments:
Thanks Doc.I'm just ready for fall and winter to come already.
Member Since: Posts: Comments:
Guess it would be inaccurate for me to call the NAVGEM, the NOGAPS even though on the model suites it still shows up as NOGAPS, same case as the GFS which still shows up as the AVNO and AVNI.
Member Since: December 31, 1969 Posts: Comments:
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.


Why dos dr m all way say this above I do not think Dr m do not look at mode runs be for he makes his blog all so dr did not check the nhc two this am be for posting if he did then he will find there is a 0% on the two


All so haven't the gfs ECW and cmc been forecasting someone in the next few days or so in the gulf and off the coast of Africa
Member Since: December 31, 1969 Posts: Comments:



tropical wave producing some pretty wet weather in dominica........
Member Since: Posts: Comments:
Yayy Doc mentioned the Experimental FIM! :)

"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."
Member Since: December 31, 1969 Posts: Comments:
Thanks Dr Masters.
Member Since: Posts: Comments:
Interesting. Hmm...
I guess the models are just all over the place.
Member Since: Posts: Comments:
Thank you Dr Masters for this very important blog that explains all about the models.
Member Since: Posts: Comments:
Good morning all, heat advisory here again in NOLA although I'm not quite sure what is different about today than the last 200 august 7ths lol. Have a great day
Member Since: Posts: Comments:
Thanks Doc !
Member Since: Posts: Comments:
Good Morning All!
Member Since: December 31, 1969 Posts: Comments:
Thanks Doc for the update :o)

Taco :o)
Member Since: Posts: Comments:

Viewing: 36 - 1

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 | 40 — Blog 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