Knoxville, IA Weather

Key Messages

- Cold front across northern Iowa today will result in highs in the 50s while central and southern Iowa remain in the mid 70s. Spotty rain showers will be possible, mostly Sunday evening into Monday north.

- Warm temperatures in the 60s and 70s continue through the upcoming week with multiple rain chances.

Short Term

Issued at 231 AM CDT Sun Oct 25 2026

Two boundaries are across Iowa early this morning, associated with the trailing upper level trough across the central US. The first is a wind shift which has resulted in a notable fine line on radar through the overnight hours as it pushes to the southeast. The second is the surface cold front where cooler air is slipping into northwest Iowa. Temperatures there are around 10 degrees cooler than the rest of the state. Scattered light rain has developed along and behind the cold front. The cold front stalls out today, and may even lift back north a bit as the southwest US upper low lifts into the midwest. This will keep most of Iowa in southerly flow with highs in the mid 70s while far northern Iowa will see highs in the 50s behind the cold front. There is some uncertainty as to how far the cool front will retreat today and that will impact highs across northern tiers of Iowa counties this afternoon.

The wave continues lifting into the midwest on Monday with persistent spotty showers along the cold front that will be draped across northern Iowa. Meanwhile central and southern Iowa will see another day with highs in the 70s, though with increased cloud cover.

Long Term

Issued at 109 PM CDT Sat Oct 24 2026

The 500 mb trough currently over the southwestern CONUS eventually lifts over the midwest Monday night into Tuesday, with the resultant surface low generally passing over eastern Nebraska and South Dakota. Increased theta-e advection in the warm sector of this low will bring the potential for light rain to portions of central Iowa on Tuesday, although dry air intrusion from the southeast and slight displacement from the main synoptic lift will likely limit precipitation coverage. A southwest flow pattern generally dominates the central US through the week, maintaining a steady stream of moisture and warmer, southerly air. As waves eject through this pattern, we'll see additional rain chances throughout the remainder of the forecast. Some of these rain chances look to also have some weak instability associated with them, suggesting the potential for a few thunderstorms as well. The pattern remains relatively active into next weekend, so will continue to monitor any rain and thunderstorm potential as we progress through the week.

Aviation

Issued at 627 AM CDT Sun Oct 25 2026

VFR cloud cover across Iowa through the TAF period. Scattered showers will be in place in northwest Iowa to South Dakota and Minnesota, but should remain away from TAF sites through the period. Wind today will be light under 10 kts from the northeast for sites KFOD/KMCW. Meanwhile the front will be hung up across central Iowa with KALO/KDSM seeing variable direction through the day. At KOTM southerly winds should last through much of the day until the front arrives after 05z.