Half of Indiana (shaded in dark green on the map, above-left) has a marginal risk of severe thunderstorms between 9 a.m. EDT today and 8 a.m. EDT tomorrow, according to the “Day 1 Convective Outlook” that the National Weather Service Storm Prediction Center (SPC) issued at 8:52 a.m.
The primary risks are damaging straight-line thunderstorm winds of 58 mph or stronger and hail of one inch or more in diameter. The probability of either occurring within 25 miles of any point in the slight risk area is five percent.
The normal hail probability for any May 12 is about one percent, so today’s probability is roughly five times normal.
There’s no reason to be alarmed by a marginal risk, but if you live in that half of Indiana, it’s wise to remain weather-aware today, especially if you’ll be involved in any outdoor activities (e.g. baseball games, etc.). Remember that all thunderstorms, severe or not, bring lightning, which kills people who are outdoors.
The SPC plans to update its outlook for today by 12:30 p.m. EDT.
Extreme southern Indiana (shaded in yellow on the map above) has a slight risk of severe storms tomorrow, according to the “Day 2 Convective Outlook” that the National Weather Service Storm Prediction Center issued early this morning. The slight risk area includes Vincennes, Jasper, Corydon and Evansville, among other communities.
A slight risk on a day-two outlook means a 15 percent probability of any one or more of the following types of severe weather occurring within 25 miles of any point between 8 a.m. EDT tomorrow and 8 a.m. EDT Wednesday:
Damaging straight-line severe thunderstorm winds of 58 mph or stronger.