Hurricane Irma is strengthening in the Atlantic and Governor Rick Scott has declared a state of emergency for Florida but is there any real threat to the sunshine state?
Forecasting weather is not a science; it’s an art. Many factors make it nearly impossible to predict where major tropical events will take place.
Let’s take a spaghetti model for instance. These models are a simplistic way to convey a lot of tropical information quickly. However, they don’t portray any impacts caused by the storm.
Meteorologists often stress the importance of waiting until the storm moves closer because forecast models must only focus on the center point of a tropical system. That center point may or may not be accurate.
In fact, if a forecast model has a direct hit to a particular city when the storm is five to seven days out there should be a sigh of relief in the city being targeted. A tropical system usually never hits the area that is targeted because of unpredicted variables.
A study by Aubrey Samost looked at the accuracy of predicting current hurricane paths. Since the 1950’s the National Hurricane Center has been forecasting 120 hour, 96 hour, 72 hour, 48 hour, 24 hour, and 12 hour forecasts. The study found that hurricane path errors decrease as the time before landfall decreases.
Though that mistake margin has improved over the years with the advancement of tropical system prediction models (NOAA, 2004), there is still a lack of accuracy for hurricanes a week out.
| Days Before Landfall | Error in miles |
| 5 | 350 |
| 4 | 290 |
| 3 | 230 |
| 2 | 160 |
| 1 | 100 |
The chart above was supplied in Samost’s article.
Should these errors hold true, then Miami might not be in as much trouble as media meteorologists predict it is. As of now, forecasters believe Irma will not be close to the Florida coastline until Saturday so a block party might be in order for South Florida.
And should Irma still target and hit Miami, well the intensity, amount of rainfall, and wind speeds is still uncertain from spaghetti models. Bunker down Floridians, we’ve still got a few days before we know for sure where and who Irma is targeting.
