textproduct: Central Illinois

KEY MESSAGES

- Beautiful, but cool summertime weather is in store for this afternoon into Monday. Highs in the 70 and lows in the 50s.

- After a brief lull, a marginal risk for severe weather returns Tuesday, with a 30% risk for severe weather on Wednesday.

DISCUSSION

Issued at 252 AM CDT Sun Jun 14 2026

Showers and thunderstorms will slide through central IL into the morning. They have taken their time to arrive. There still is a marginal (level 1 of 5) risk for severe weather tonight, mainly for damaging winds and small hail. By the afternoon, the entire forecast area should be dry, which will last until Tuesday, as a high pressure sets up over the region this afternoon. The main focus for today is the northwesterly winds that will be around 15-20 mph and gusting up to 25-30 mph. Highs today into Tuesday will be in the 70s, and lows in the 50s. Temperatures through the week will remain around normal, with highs in the upper 70s to low 80s.

A weak wave/frontal boundary is forecast to move through on Tuesday, bringing showers and thunderstorms back into central IL. SPC has a marginal risk for severe weather for eastern IL, east of I-55. The GFS shows strong bulk wind shear (45-55 knots) but lower MUCAPE (~1000 J/kg). The hazards of concern are gusty (up to 60 mph) winds and near severe/severe hail. The storms Tuesday could be strong to marginally severe during the afternoon into the evening. Uncertainty exists on how strong the storms could become.

Wednesday looks to be a better day for severe weather and potential flooding over Tuesday's storms. SPC has a 30% severe weather risk over the majority of the forecast area. The better environment looks to be focused over northern MO and far west-central IL, with the parameters waning as you go east and with time. However, the LLJ should be increasing as the QLCS approaches IL. WPC has introduced an excessive rainfall slight risk for Wednesday. PWATs look to be around 1.9-2.1 inches. With many rivers/streams already at or near flood and saturated soils, flooding could be a concern through Wednesday. Stay tuned for future forecasts as the details become more apparent into the new week.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 602 AM CDT Sun Jun 14 2026

After some showers this morning and the cold frontal passage, TAFs turn dry and VFR beyond 17z. Ceilings will be bouncy this morning. Mainly VFR but during a shower, ceilings could drop as low as IFR at times. CMI may also see some light fog this morning, quickly dissipating as winds pick up and rain moves in.

Winds shifting out of the northwest this morning will gust to 20-25 knots this afternoon, sustained 10-15 knots. They will become light and variable this evening, continuing into the end of the 12z TAF period.

ILX WATCHES/WARNINGS/ADVISORIES

None.