Peoria, Ill. (WMBD) — The weather pattern will remained unsettled this week as a series of storm systems impact Central Illinois. While nuisance rain showers are expected Tuesday night and Wednesday, a cold front could help bring a few stronger storms to the region late Wednesday night and early Thursday morning.

Key Takeaways

  • Storm Timing: 12 am to 6 am Thursday
  • Primary threats
    • Hail up to quarter size
    • Locally heavy rain
    • Frequent lightning
  • While storms will be widespread, most will not see severe weather

The Storm Prediction Center has issued a Level 1 Threat (Marginal Risk) for severe storms over Central Illinois. This means that the severe weather threat is expected to remain isolated and limited in duration, coverage and intensity. In other words, not everyone will experience severe weather.

Storm Setup

Instability

Since Monday moisture from the Gulf of Mexico has been surging north into the Midwest. This moisture will continue to move into Central Illinois and eventually lead to dew points reaching the upper 50s and lower 60s. This moisture will bring elevated instability to the area which will help feed thunderstorm develop late Wednesday night.

Wind Shear

Strong winds aloft within the jet stream are expected to move over the region Wednesday night and Thursday. These strong winds will contribute to moderate wind shear which will be sufficient for a few storms to become severe and capable of producing hail up to 1.00″ in diameter.

Storm Timing

While a few stray showers and maybe a thunderstorm will be possible during the day on Wednesday, the risk of stronger storms will come late Wednesday night and early Thursday morning (12 am to 6 am Thursday). The storms are expected to develop ahead of a cold front which will drop through the region Thursday morning. Once the front moves through the risk of severe storms and rain will shift into southern Illinois where the cold front will eventually stall. This stalling front will lead to training thunderstorms and will likely lead to a widespread 2-3 inches of rain for the southern part of the state.

The Next Weathermaker

Another storm system is expected to form along the stalled front and lift northeast through Illinois. This will result in rain showers redeveloping across Central Illinois Friday afternoon. Rain will be likely Friday night but may mix or change to snow north of I-74 after midnight. Snow accumulation is not expected at this time.