Weather Whys March 19, 2015

Q: You sometimes hear in the forecast of either “scattered” or “isolated” showers.  What is the difference?

A:  The terms can be confusing, but both refer to rain chances, says Brent McRoberts of Texas A&M University. “In general, weather forecasters use the term ‘isolated’ to refer to the possibility of showers being small in any given location, at around 10 to 20 percent,” he explains. “Scattered showers mean rain chances are a little higher – usually in the 30 to 50 percent range. So you have a better chance of getting wet if the forecast calls for scattered showers rather than isolated showers.”
Q: Is there another term for probable rainfall?

A: Yes, just to make it a bit more confusing, add the term “numerous” to the mix, he adds.  “If the forecast says numerous showers, that means you have even better rain chances,” McRoberts says.  “The National Weather Service defines a forecast of numerous showers for a given location as a 60 to 70 percent chance of receiving precipitation. Sometimes this same type of forecast may also be referred to as ‘widespread.’  So on a spring day, if the forecast calls for numerous or widespread showers, you are more likely to get rainfall than a forecast that calls for isolated or scattered showers.”