INDIANAPOLIS (WISH) — Every decade, a new climate data set is put into place. The new one just came out and shows some interesting changes for Indianapolis.
The new data set uses the time period 1991-2020, eliminating the 1980s and adding the last 10 years.
Mike Ryan, a meteorologist from the National Weather Service in Indianapolis explained, “This 30-year climate normal is used in order to give us a look at what’s happening in our current climate. We’re able to see trends and this 30-year period is of time is long enough to get a good snapshot across the country.”
The new data set shows an increase in temperatures and precipitation for much of Indianapolis. We’ve noticed a slight increase in yearly temperature from the previous period, more than an inch of precipitation and a drop in our seasonal snowfall.
There was a decrease in snow for December but an increase in snow for March.
Eleven of the 12 months had an increase in temperature, the greatest in December at 1.7 degrees. Nighttime lows also increased 11 of the 12 months.
Ryan has been involved with climate data just about his entire career at the NWS and has been through three different climate data changes. He’s noticed a rise in nighttime lows in the previous two climate cycles in Indianapolis.
“I think there are a couple of factors in play. I think a natural change in climate is a component. The other fact: I wonder if it has something to do with the urbanization near the airport, keeping those temperatures a little bit warmer at night. Could it also be at night where we have a north or northeasterly wind. which would bring warmer, modified air over the city out to the southwest over the airport?” Ryan said.
Ryan noted the decrease in snowfall for the year wasn’t a huge surprise because Indianapolis really hasn’t seen huge snowfalls lately. However, he said there may be a seasonal shift with snow.
“There was a rise in snowfall in March. It looks like in recent years we’re seeing more snow and bigger snowfalls a little later in the season, like March and April. It could be we’re seeing the snow season shifting a little bit farther,” Ryan explained.
Ryan cautioned that just because this new data shows it may be wetter than normal, we will still see extremes. “We may have periods of the year that are wetter and we may have periods of the year that may be drier. Those extremes may vary and will continue.”