INDIANAPOLIS - By late July, the temperature in Indianapolis is regularly hitting 90 degrees or more, but not this year.
Through the first 17 days of July, Indianapolis temperatures for the month were the third-coldest since records began in 1850.
A remarkably cool air mass in the area last week contributed greatly to that, but it had been cooler than normal before that, too.
The National Weather Service in Indianapolis said that 18 of the first 20 days of July had high temperatures that were below average in Indianapolis.
Indianapolis' average temperature July 1-20 was just 70.3 degrees, nearly 6 degrees below average.
Typically at this time of year, the high temperature is 85, but Indianapolis has been well short of that most of the month, only hitting or exceeding that mark twice.
While temperatures Tuesday could hit 90 degrees for the first time this season, it won't last.
"The cold front that slides over our area bringing showers and storms will also bring much cooler air to the forecast as we end the week," said StormTeam 6 meteorologist Ashley Brown.
Why is it cooler this summer?
The jet stream, which normally stays well north of central Indiana this time of year, has been tracking a lot further south than usual.
That allows cooler air normally confined to Canada to spill down into the region. Other cities in the Great Lakes have also had below-normal temperatures so far this summer.
While it's likely there will be bursts of heat during the remainder of the summer, the overall pattern appears to be trending toward cooler-than-normal temperatures the rest of the season.
It's possible we'll even be breaking out the sweatshirts a little early this year.
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