Bolan, IA Weather

Key messages

- Sunny and dry Thursday afternoon with rain and a few thunderstorms returning tonight.

- Rain will remain in the forecast for much of Friday and the daytime Saturday.

- After a break Sunday, rain and storms will return Sunday night and last through at least midweek.

Short term

Issued at 115 PM CDT Thu Oct 29 2026

The remaining stratus and fog burned off in the late morning, so most of Iowa will be clear this afternoon. Some easterly flow will come off high pressure over the Great Lakes region and into Wisconsin, which opens up the chance for radiational cooling in northeast Iowa. Lows have been adjusted with some mid 30 possible in northeast Iowa. Southerly flow will reestablish itself overnight in the south. This is in response to a shortwave ejecting into the region, which will also usher in our next chance of rain for much of Friday. Early on in the event (mainly around sunrise Friday) some scattered nonsevere thunderstorms will be possible in the southern half of Iowa. Rain will persist through the day and another round of storms are possible with the return of the LLJ. While most all the state will see rain, highest amounts will be in the southern half with totals over half an inch. Thunderstorms will push amounts close to an inch in localized areas.

Long term

Issued at 115 PM CDT Thu Oct 29 2026

The shortwave will be slow to exit the region and troughing over the Rockies will pull the moisture axis north. This will result in continued rain chances moving into northern Iowa through the day Saturday. Light showers will linger in southern Iowa through Halloween night as the moisture axis is pulled west. Amounts Saturday will give the highest amounts to northern Iowa.

Height rises will reside over Iowa on Sunday, and the advection wing will have lifted into Minnesota. This will keep Sunday cloudy and cooler, but dry. The complex synoptic trough will increase southwest flow Sunday night with rain beginning to arrive. Its influence will keep precipitation chances going all the way through at least Wednesday. The highest chance for thunderstorms looks to be Monday afternoon and evening. This is when the lower and upper level jet align parallel to the cold front and the instability axis makes a run north. Severe weather is questionable at this range given the overnight and morning storms; cloudcover from these will make surface destabilization challenging. Beyond Monday, a northern stream wave will usher in another cold front from the northwest, reinforcing the wrap around precip from the first system. Widespread moderate rain is possible from the cumulative rounds of rain. Most of the state could see a total between 1 to 2 inches, but the rainfall will be spread in a large enough timespan that hydrology impacts will be minimal. A cooldown follows the complex of waves with high temperatures returning to the 50s by next weekend.&&

Aviation

Issued at 1238 PM CDT Thu Oct 29 2026

VFR conditions and mostly clear skies over the next 6 to 12 hours. Rain and some early thunderstorms will migrate north, affecting KDSM and KOTM first. Have added a Prob30 group to reflect when thunderstorms are most likely which will also pose the risk of at least MVFR cigs and vsbys. Rain will overspread to all terminals by the end of the TAF period and widespread IFR cigs won't be far behind near 18z.

Watches, warnings and advisories

None.