Want to know in detail how a tropical storm might impact your neighborhood? Don’t refer to the cone of error.
The National Weather Service now offers Tropical Cyclone Potential Impacts – weather.gov/tcig – a site that provides color-coded graphics showing a low, moderate or high probability of high winds, storm surge, flooding or tornadoes moving into your area.
“It’s about helping people make the best decisions possible,” meteorologist Robert Molleda said during the Governor’s Hurricane Conference in Fort Lauderdale on Friday.
The National Hurricane Center’s cone of error depicts the potential five-day path of a storm and how strong it might be along the way. However, it doesn’t tell people what specific dangers they might face since hurricanes can cause damage hundreds of miles from their cores, Molleda said.
To use the weather service’s potential impacts site, click on your region on the map. Then click again on your specific community. A box will pop up giving you details on what hazards might lay ahead.
“It tells you what you can reasonably expect, taking into account the forecasted track and intensity,” Molleda said. “We’re not giving the worst-case scenario or the best-case scenario, but rather somewhere right down the middle.”
In addition to weather service’s graphic site, the wind speed probabilities graphic on the hurricane center’s site, nhc.noaa.gov, provides a broad picture of which areas might receive high winds.
“You get an idea of where the center might go and the windfield of the entire storm,” he said.
All of the graphics convey uncertainty because storm predictions are never perfect. For instance, when a hurricane is 24 hours out, the average error in the forecast track is about 50 miles, which could make a big difference in whether a community is spared or clobbered.
“The storm could shift a little and people would be caught off guard,” Molleda said.
Weather officials also emphasized that while coastal residents commonly fear a tropical system’s winds, the most deadly hazards are storm surge and inland flooding, which cause 85 to 90 percent of the deaths.
“People do not see the threat from water that storms pose; they’re so focused on the wind,” said senior hurricane specialist Dan Brown, of the hurricane center.
While all tropical systems hold numerous dangers, people tend to forget about battering waves and rip currents, Brown said.
“A hurricane doesn’t even need to be close or make landfall to cause these,” he said.
The week-long Governor's Hurricane Conference, the largest of its kind in the nation, concluded on Friday. After being held at the Broward Convention Center in Fort Lauderdale for eight years, it will move to Orlando in 2014.