Peoria, ILL. (WMBD) – The National Weather Service has issued a Flash Flood Watch which is in effect for Central Illinois from 7 pm Thursday through 7 am Saturday. A tropical air mass is in place over much of Central Illinois and will help fuel multiple rounds of heavy rain through the start of the weekend.
- Heaviest rain comes Thursday night and Friday night
- Widespread 3-5 inches of additional rain likely, locally higher amounts possible
- Severe storms possible Thursday night, Friday and Saturday
The next round of storms will be the first of multiple rounds of heavy rain to move through Central Illinois over the next few days. Storms will develop along an outflow boundary located along the Iowa/Missouri border as the low-level jet stream ramps up this evening. These storms will then track east into Central Illinois after 8 pm producing very heavy rain with rainfall rates of 1-3 inches an hour expected.
A few strong to severe thunderstorms are also possible tonight, particularly south of I-74 where the Storm Prediction Center has placed a Slight Risk (Level 2 Threat out of 5). Flash flooding and damaging winds are the primary threats but hail and isolated tornadoes are also possible.
Rainfall Forecast Through Tonight
Widespread rainfall amounts of 1-3 inches are expected tonight with locally higher amounts possible. The heaviest rain is expected to fall along and south of I-74. The Weather Prediction Center (WPC) has placed Central Illinois within a slight risk for flash flooding through 7 am Friday.
Friday & Friday Night
Remnants from Thursday night’s storms will shift east of Illinois early Friday morning. Additional thunderstorms are expected to develop across the region in the afternoon and evening with another round of heavy rain expected Friday night. Any storms that can develop Friday afternoon may be severe with hail, damaging winds and isolated tornadoes possible. This will largely depend on the evolution of tonight’s storms and whether we see any clearing in the wake of the early morning storms. The Storm Prediction Center has a Slight Risk (Level 2 out of 5) in place for much of the region once again.
Rainfall Forecast Friday and Friday Night
The flash flood risk will be higher Friday night as heavy rain is expected to fall over already saturated soils. Another 1-3 inches of rain is possible through Friday night with locally higher amounts possible. WPC has issued a Moderate Risk for flash flooding across Central Illinois.
Saturday & Saturday Night
The heavy rain from Friday night is expected to move east of the region by sunrise. However, a slow moving cold front is expected to trigger additional thunderstorms across the region throughout the afternoon. We expect clouds to break enough throughout the day for instability to increase ahead of the approaching cold front. Sufficient wind shear should allow storms that develop to become strong to severe.
SPC has issued a Marginal Risk (Level 1 out of 5) for the region but the risk could increase in later outlooks. Damaging winds and heavy rain would be the primary threats but isolated hail and tornadoes are also possible.