The humidity has surged and the air is warm, just throw in a frontal system and a nighttime jet stream, the threat for a few thunderstorms are on the rise.
Temperatures have reached the high 80s and even lower 90s Wednesday afternoon before clouds developed, equaling the warmest day of the year in Indianapolis with a preliminary high of 88-degrees. The added late day cloud cover may aid in the reduction of storm development early this evening however a slow moving front will encourage a few/handful of storms to initiate through 8 pm this evening. We are monitoring trends and the conditions at least for this first round, it doesn’t look too impressive for these storms grow in large numbers. At this point we place a minimal 20% coverage early evening thunderstorm risk. The location of these storms favor north or along I-70, and then locations south of the front and where more late day sun has occurred.
LATE NIGHT STORMS?
There is a growing chance that new storms will emerge late tonight as a nighttime jet stream activates additional clusters or batches of storms into the early morning hours. These storms could be heavier with locally heavy rainfall, some damaging wind gusts and prolific lighting. The coverage on these storms is expected at only 30%. The Storm Prediction Center has included a portion of central Indiana in a risk of severe storms through 8 am. We will monitor these trends, and have updates through the evening.
UPDATE 9:30 pm
Renewed storm activity nearing Illinois / Indiana border, Vermillion County just before 9:30 pm Wed. SE bound storms getting boost as nighttime jet ramps up. Activity to become more widespread into southwest central Indiana before midnight.
UPDATE 11:00 PM
Slow moving drenching downpours in western Indiana. SERIOUS threat underway. Radar and ground reports of 3″ totals. South Vermillion HS gauge (Fairview Park) 3.35″ & still raining just before 11 pm