Jefferson, IA Weather

Key Messages

- Warm, dry, and breezy today with highs in the mid to upper 70s and winds gusting 25-30 mph across northern and western Iowa.

- Warmer weather continues on Saturday. A slow moving cold front will bring cooler temperatures in the upper 50s to low 60s across northern Iowa on Sunday while the rest of the state continues to see mid 70s.

- Rain chances and relatively cooler temperatures return early next week, around Monday into Tuesday.

Short Term

Issued at 207 AM CDT Fri Oct 23 2026

Clear skies are in place across eastern and central Iowa early this morning while an area of cloud cover is across western Iowa. This cloud cover is associated with an area of convergence and weak moisture plume on the eastern edge of the western US trough that will continue to deepen as it slowly pushes into the plains today. Meanwhile in the clearer areas to the east patchy fog is developing in valleys and is notable on satellite, mainly in far NE Iowa into southern Minnesota and Wisconsin. As the western US trough deepens today the pressure gradient across western Iowa increases with a 40+ kt 850mb jet setting up across the plains. Dry low levels will allow for modest mixing, and while we won't tap the strongest winds, gusts of 25-30 mph will be possible across northern and western Iowa through this afternoon. With warm temperatures this afternoon in the mid to upper 70s and relative humidity falling to around 35-45%, the breezy conditions in northern and western Iowa will result in heightened fire weather concerns for those areas. This is primarily an agricultural concern with cured crops, whereas grasses remain fairly green thanks in part to the wet September.

By Saturday the western US trough is expected to deepen into a cutoff low across the southwest US, helping to ease the pressure gradient across the plains and resulting in less breezy conditions. The cold front gets hung up across South Dakota and Nebraska, keeping Iowa dry with temperatures in the mid to upper 70s once again.

Long Term

Issued at 207 AM CDT Fri Oct 23 2026

By Sunday the cold front begins to slip in far northern Iowa with highs there in the upper 50s to low 60s on Sunday. Meanwhile most of Iowa will be in the mid 70s once again on Sunday. A few isolated showers are possible in northern Iowa on Sunday, however dry air will mitigate most development. As the cutoff low across the southwest US finally lifts into the midwest Monday into Tuesday moisture increases and will allow for spotty showers across the area. The cool front finally sinks across the area bringing temperatures down into the 60s. There will be a brief respite with weak mid-level ridging before the stronger trough from the Pacific Northwest swings through our region in the middle to end of next week. That system will push a stronger surface trough through and sweep out most remaining moisture from the earlier systems, bringing quieter autumn weather for at least a couple of days afterward in the extended forecast.

Aviation

Issued at 1037 PM CDT Thu Oct 22 2026

Confidence remains high in VFR conditions through the period at the terminals. While far insufficient to warrant any mention beyond here, there could be isolated fog in the Cedar or Winnebago River Valley Friday around sunrise. Otherwise, winds from a southerly direction will increase through the morning reaching their peak in the afternoon. Sustained winds over 12 knots and gusts of 20 to around 30 knots during this period will be common west of a MCW-DSM-LWD line with winds loosing some strength into Friday evening statewide.