Percy, IL 62272 Weather

Key messages

- Light showers are expected Saturday night through Sunday morning with mainly dry conditions this weekend otherwise.

- The next opportunity for widespread, beneficial rainfall will be in the Monday night-through-Wednesday morning timeframe.

- Above average temperatures will persist through at least early next week.

Short term

Issued at 217 PM CDT Fri Oct 30 2026

A warm front is currently draped along the I-70 corridor and is expected to slowly advance northward into northeastern MO and west- central IL tonight. Scattered showers will continue to lift northward ahead of the front, but conditions overall will remain largely dry through tonight.

The first in a pair of upper-level shortwave troughs will pass over the CWA Saturday morning into afternoon providing at least widespread clouds. Mainly dry conditions are anticipated to continue on Saturday as saturation and forcing will be concentrated in the mid-levels above a layer of easterly flow feeding dry air into the area, making it difficult for more than sprinkles or a brief shower to reach the surface. The second shortwave trough will arrive sometime overnight Saturday night into Sunday morning, which 40 to 70 percent of HREF membership has producing light (measurable) showers in that timeframe as low-level flow begins to more favorably veer to southeasterly increasing moisture advection. The greatest coverage and "heaviest" showers will be across southeastern MO/southwestern IL where there are even 30 to 50 percent probabilities of 0.25"+ in global ensemble model guidance. Forecast soundings suggest that low-level clouds and patchy drizzle could linger beyond the main round of showers in the morning. Persistent cloud cover will limit the diurnal range of temperatures this weekend, although still remaining above average with high temperatures in the upper 60s to low-70s F on Saturday and then 60s F on Sunday with thicker cloud cover and precipitation.

Long term

Issued at 217 PM CDT Fri Oct 30 2026

A potent upper-level trough will slowly propagate eastward across the central CONUS Monday through Wednesday. Although there are lingering differences across model guidance on the exact structure and speed of the trough, there are still projections of anomalous, deep meridional flow with anomalous PW around the 99th climatological percentile and a slow-moving front all aligning to provide an opportunity for widespread, beneficial rainfall across the CWA. NBM probabilities of 1"+ of rainfall have been consistently around 50 to 80 percent, highest in central and northeastern MO. Ensemble model membership generally agrees on most of this rain falling in the Monday evening-through-Wednesday morning timeframe. The only impact from this system may just be beneficial rainfall with present indications that instability will be limited enough to preclude a clear heavy rainfall or severe weather threat with poor mid-level lapse rates from widespread clouds and precipitation along with occlusion tending to "pinch off" the unstable warm sector. Still, strong deep-layer wind shear will likely be present, leaving instability trends worth monitoring going forward. NBM interquartile temperature ranges expand to around 10 F by next Thursday, spanning between continued above average temperatures and cooler temperatures near average. This spread is attributed to uncertainties in the characteristics of the post-frontal airmass including the structure of the trough impacting the airmass' origin.

Aviation

Issued at 1152 AM CDT Fri Oct 30 2026

Predominantly dry and VFR flight conditions will persist through the TAF period. Isolated showers are expected in northeastern MO/west- central IL through early afternoon and then sprinkles or light showers areawide on Saturday, but impacts are unlikely. Light, mainly easterly winds will continue.

Watches, warnings and advisories

MO: None. IL: None.