textproduct: Des Moines

KEY MESSAGES

- Wintry mix of precipitation possible southwest late this afternoon and evening. Light snow possible north, mainly west of Interstate 35.

- Warming trend arriving Sunday and into next week but to what degree will be determined by how much stratus develops over the state.

DISCUSSION

Issued at 346 AM CST Fri Jan 2 2026

Ridge of high pressure is extending from eastern North Dakota, though Minnesota and into northeast Iowa early this morning. A broad area of stratus remains wedged under the high with any clearing over the northeast half of Minnesota and into parts of northern Wisconsin. Precipitation has been developing over southeast Wyoming and western Nebraska as strong theta-e advection is moving across that area ahead of an upper level system. This precipitation will be moving east towards west central and southwest Iowa ,however, it will be moving into the drier air associated with the high pressure and some of the energy with the system will be diving more southeast so the forcing will not be as dynamic as it arrives into the state. The current stratus across Iowa will be holding much of the state below freezing for high temperatures today. A warm nose will be retreating south across Iowa as the precipitation arrives which could lead to a brief period of freezing rain before changing to light snow. There will be some moisture discontinuity with this system. Mid-level drying will arrive in the wake of the upper level short wave passage and that may occur before the lower levels saturate. This may lead some freezing drizzle as ice introduction aloft is lost leaving only supercooled droplets in the saturated layer. Confidence in any icing is low enough to preclude any headlines at this point otherwise it will be a diminishing area of precipitation/light snow as it arrives.

The area of high pressure will remain over Iowa on Saturday though the stratus will remain along with perhaps some lingering flurries in the morning. Warm advection will commence as the high moves to the east Saturday night into Sunday. Much warmer air aloft will be over Iowa on Monday. We don't have to look too far back when very warm air moved over Iowa and the NBM way over forecast high temperatures as a significant low level inversion set up and it resulted in days of fog and stratus. Are we setting up for a repeat? Perhaps as it does appear a steep low level inversion is possible. There is less snow cover than the last event and dew points initially will be lower. The last event, not only did warm dew points over the snow cover fog up, but eventually the even warmer dew points in the 40s arrived and it fogged up over the colder ground. At some point early to mid next week, stratus will have an impact on temperatures. No significant systems otherwise though mid next week.

AVIATION /12Z TAFS THROUGH 12Z SATURDAY/

Issued at 530 AM CST Fri Jan 2 2026

A broad area of IFR/MVFR stratus to begin the period. These cigs will gradually improve today as drier air moves in from the north. Despite the dry air, that stratus will likely persist at most sites through the period though it may rise to VFR for a period before a system arrives overnight and lowers cigs again. Some light precipitation is possible at KDSM/KFOD overnight which at this time appears to be light snow. The wind will remain light from the north/northeast.

DMX WATCHES/WARNINGS/ADVISORIES

None.