textproduct: Des Moines

KEY MESSAGES

- Winter Weather Advisory in effect for this afternoon. 1-3 inches of snow possible. Ice amounts have trended down.

- Additional snow chances on Saturday with a similar system, just with colder temperatures. Snow amounts extra sensitive to snow ratios.

- Bitter cold temperatures Saturday night into Sunday. Cold weather headlines highly likely.

DISCUSSION

Issued at 245 PM CST Thu Dec 11 2025

Snowfall rates are peaking this afternoon across central Iowa with local visibilities under 1 mile being reported at places like Marshalltown. Forcing is largely driven by a strong fgen band extending into the fringes of the dgz and paired with low static stability. Forecast update from this morning remains on track with a band of 1 to 3" possible across much of the area. Locally higher amounts are possible where rates peaked this afternoon. The Winter Weather Advisory will continue through this afternoon.

Stratus will hang around the state overnight with a few degrees of warming taking place on Friday. A cold front will pass over the state through the afternoon, sending temperatures on a downward trend before sundown. Little warming occurs on Saturday. Highs will mostly be in the single digits. Another quick moving clipper brings another round of snow during the day Saturday. ECMWF AIFS, which has been notably skilled in placement of systems this winter, places the snow band a county southwest of the snow axis from today. The Saturday snow amounts will be higher, owed to the cold temperatures. In soundings, most all of the Saturated layer is in the DGZ (outlier is the warmer midlevels of the NAM). This supports above climo SLRs, somewhere on the order of 20:1. Cobb outputs vary by model due to how much lift is present. Right now, the consensus is forcing is nebulous (-5 microbars or less) which explains why most models cap totals at 4". We'll continue to watch how the SLRs evolve closer to time.

An arctic high settles across the region and shoves the clouds away from the state Saturday night. Temperatures will plummet. Lows below zero will be common statewide, close to -20 in northern Iowa. By Sunday morning, wind chills will be near -30 degrees. Cold weather headlines are likely. Reprieve is on the way from the intense start to meteorological winter. A ridge will build into the central CONUS and give Iowa a chance of 40 degree highs next week.

AVIATION /00Z TAFS THROUGH 00Z SATURDAY/

Issued at 535 PM CST Thu Dec 11 2025

Snow is ongoing across much of central and south central Iowa to start the period but will be ending from northwest to southeast through 03z. A mix of MVFR and VFR cigs with local IFR/LIFR into southern Iowa. This mix of MVFR/VFR will likely persist through the evening with MVFR stratus becoming more prevalent overnight and into Friday. Easterly winds will gradually rotate to north/northwest overnight into Friday with gusty winds expected by the afternoon when a cold front arrives.

DMX WATCHES/WARNINGS/ADVISORIES

Winter Weather Advisory until midnight CST tonight for IAZ004- 005-015-016-023>026-033>039-046>050-060>062-074-075-086.