06/17/2026
🌪️ SEVERE WEATHER OUTLOOK – Wednesday, June 17, 2026 (11:28AM CDT Update)
SPC Risk Level: MODERATE (Level 4 of 5)
Valid through June 18, 2026 12:00 PM CDT
📍 Major Cities in Risk Zones
🔴 MODERATE Risk: Springfield, IL, Champaign, IL, Terre Haute, IN, Bloomington, IN
🟡 SLIGHT Risk: Baton Rouge, LA, Hattiesburg, MS, Jackson, MS, New Orleans, LA
🌪️ Tornado Risk Zones
🔴 15% Tornado Risk (tornadic supercells with strong tornado potential): Champaign, IL, Bloomington, IN, Terre Haute, IN, Springfield, IL
🟡 10% Tornado Risk (overnight tornado threat near tropical circulation): Baton Rouge, LA, Hattiesburg, MS, New Orleans, LA
What the Percentages Mean
A 15% tornado risk means there is a 1 in 7 chance of a tornado within 25 miles of a point. Intense tornadic supercells capable of producing strong tornadoes are possible across central Illinois and Indiana this afternoon into evening.
A 10% tornado risk means there is a 1 in 10 chance of a tornado within 25 miles of a point. Overnight and pre-dawn tornadoes are possible near the tropical circulation affecting southeast Louisiana and southern Mississippi.
📝 Overview
An intense and fast-moving shortwave trough is advancing into the Midwest, accompanied by a 90+ knot mid-level jet and a strong southerly low-level jet. Early thunderstorms over central Illinois have produced an outflow boundary extending into south-central Illinois, which will influence the location of the main severe threat later today. Strong heating south of this boundary will create very unstable conditions by mid to late afternoon, with impressive shear profiles supporting tornadic supercells capable of producing very large hail, damaging winds, and strong tornadoes across Illinois and Indiana.
By mid-evening, a line of severe storms is expected to extend from central Missouri into southern Indiana, with damaging winds becoming the primary hazard. In the Upper Midwest, a small area of destabilization near southern Minnesota will support a few severe storms with hail and damaging winds. Meanwhile, Tropical Storm Arthur moving northward will bring a risk of overnight tornadoes across southeast Louisiana and southern Mississippi due to strong low-level southerly winds east of the circulation. Scattered storms in southeast Arizona and southwest New Mexico will pose a damaging wind threat this afternoon and evening.
⛈️ Hazards Include
🧊 Very large hail (possible with tornadic supercells in IL/IN)
🌪️ Intense tornadoes (strong tornado potential in IL/IN, overnight tornadoes in LA/MS)
💨 Damaging winds (gusts over 75 mph, especially with evening line in MO/IN and storms in AZ/NM)
🕓 Timeline
12 PM–5 PM CDT: Severe storm initiation and intensification across central IL and IN with supercells producing large hail, tornadoes, and damaging winds
5 PM–9 PM CDT: Severe storms evolve into a damaging wind line from central MO into southern IN
9 PM–12 AM CDT: Overnight tornado threat increases across southeast LA and southern MS near Tropical Storm Arthur
12 AM–12 PM CDT: Gradual weakening of storms with lingering severe threat in LA/MS and AZ/NM
📌 Regional Notes
🔴 Illinois/Indiana → Central IL and IN: Intense tornadic supercells with very large hail and damaging winds expected this afternoon
🟡 Louisiana/Mississippi → Southeast LA and southern MS: Overnight tornado threat associated with Tropical Storm Arthur circulation
🟡 Arizona/New Mexico → Southeast AZ and southwest NM: Scattered storms with damaging wind gusts possible this afternoon and evening
⚠️ Stay Weather-Aware
Residents in central Illinois and Indiana should remain vigilant this afternoon and evening for rapidly developing tornadic supercells capable of producing strong tornadoes, very large hail, and damaging winds. Additionally, those in southeast Louisiana and southern Mississippi need to monitor conditions overnight as Tropical Storm Arthur’s circulation enhances the risk of tornadoes. Stay tuned to local weather updates and be prepared to take action if warnings are issued.
