A weather system is exiting the Rocky Mountains and is beginning to develop a surface low pressure area. The surface low will send an associated cold front through the Hoosier state Monday afternoon and evening. Showers and thunderstorms will develop ahead of the cold front.
Rain should start to enter the state near sunrise Monday morning. Thunderstorms will begin to develop later in the morning. Some of the thunderstorms that move through central Indiana between 10 a.m. and 2 p.m. could be strong to severe. I would not be surprised if a couple of Severe Thunderstorm Warnings are issued during that time. The main threat will be strong winds and an isolated tornado can’t be ruled out. The best chance for the stronger thunderstorms will be along and south of I-70.
There will be a lull in the activity mid-afternoon before a few more showers and thunderstorms develop as the cold front enters central Indiana Monday evening. You can see in the image below that this computer models suggests there could be a couple of narrow lines of rain/thunderstorms.
Temperatures should be able to rebound back to the upper 60°s to around 70° prior to the passage of the cold front.
Winds will be on the increase starting Monday morning. By mid-morning wind gusts could reach 40+ mph. The gusty winds will continue throughout the day and in to the night. I suspect trees will shed many leaves by Tuesday morning.
Temperatures will drop Tuesday, with high temperatures in the upper 50°s to near 60°s. It remains a “fall-like” pattern for much of the coming week. There will be a chance for a few sprinkles on Thursday and a few light showers Friday.
One long-range computer model suggests a surface low developing over the Mississippi River Valley and then lifting north in to the Ohio River Valley. We’ll have to keep an eye on whether or not this pans out as it will have significant impacts on temperatures, whether we have rain or not, and sky cover. Stay tuned!