Understanding spaghetti models: How they help with hurricane prediction insight

JACKSONVILLE, Fla. – The spaghetti model conversation on social media often sparks controversy, leading to confusion and a lot of misinformation.

These graphics are intended to give an idea or prediction of where a storm could strike, but they are not to be confused with the forecast cone that the National Hurricane Center (NHC) uses to project a storm’s path.

Hurricane season is still ongoing, so it’s important to understand how spaghetti models or plots are used.

Today’s technology has grown vastly with the NHC. There are continual enhancements to predict future storms, giving better guidance in general on where a storm may hit. This gives the NHC a better idea of where to place the cone or error and how wide to make the cone.

Granted, there is still room for error; it is not a crystal ball by any means.

“Computer modeling forecasts have come very far in the last few years,” former WKMG chief meteorologist Tom Sorrells said in a story from our sister station. Models in the past helped, but on day five of the forecast, the error in the cone of projected movement still had errors along 300 to 400 miles.

“With today’s models, computing, and increased forecast knowledge, the cone is now down to about 150 miles on day four and 220 on day five. The main difference is the amount of information going in and the computing strength of computers,” Sorrells said.

How do spaghetti models work?

You will see different spaghetti models if you watch your favorite news station or have been on weathernerds.org or Tropicaltidbits.com. Weather stations have their own spaghetti models. They will typically use about 5 or 6 models close to agreement.

At times, when too much data is inputted into the system, the computer models need help distinguishing and creating an accurate model. That’s why the models sometimes don’t always agree.

The NHC has to designate a storm called an Invest to get a spaghetti plot. The computer can start simulating spaghetti plots once an Invest is formed and numbered.

Spaghetti plots run about every 6 to 12 hours, depending on the program they are using, and as the storm develops, the NHC will send in the National Oceanic Atmospheric Administration or AF hurricane hunters to fly into the system. This is where they begin feeding the computer with data for accurate information, which helps make forecasting more accurate for predicting the path of a storm along with intensity.

As the system approaches land, the models pile into one, making the cone of error smaller.

Here is a list of forecast models the NHC uses (National Hurricane Center)

Model name Model Type Main Use

American GFS Dynamical Global Model

ECMWF or Euro Dynamical Global Model

CMC Dynamical Global Model

UKMET or EGRR Dynamical Global Model

HWRF Dynamical Hurricanes

HMON Dynamical Hurricanes

GEFS/AEMN GFS Ensemble/Consensus Global Models/Estimate of Model Confidence

EEMN EuroEnsemble/Consensus Global Models/Estimate of Model Confidence

TVC# Track Consensus Estimate of Forecast Confidence

ICON Intensity Consensus Estimate of Forecast Confidence

TABs Trajectory Estimate of Shear

LBAR Basic Dynamical

CLP5 Statistical Climatology

As you can see, a lot of data is coming in from all over the world, making it sometimes easy or difficult to predict a storm and its intensity.

For more information on spaghetti models, view weather.com.