Despite the colder changes here, including the first freezing temperatures in 10 days - we are keeping the above normal streak alive. Friday mark the 18th straight day that the average daily temperature (high and low combined and averaged) was above. January 2017's average temperature is 35.9° - warmest since 2006 and tied 14th warmest all-time.
The lack of cold is a product of the jet stream or lack of the polar branch of the jet stream. It has remained well north but now takes a dive into the eastern half of the nation. That has brought the recent changes with a more seasonable chill returning. The recent warm spell from January 10th through the 25th was the warmest ever on record for the dates averaging 43°. For the first time since 1939, Indianapolis remained above freezing for 10 consecutive days - tying the record for the most with 1939.
The polar branch of the jet stream will be pointed into central Indiana Sunday afternoon and on the nose of the jet stream air will pile up. The location is favorable for air to pile up, clouds will build and present the energy to created snow.
Snow showers will spread across the state and aided by the jet stream energy bring a sticking snow. Accumulation looks to be light but it may become slick later Sunday evening.