textproduct: Des Moines

KEY MESSAGES

- Cold temperatures through Monday. Below wind chills at times this morning and again tonight/Monday morning.

- Warmer on Tuesday but have tempered the warm up in areas with snow cover and snow melt will be a slow process this week.

- A stronger system possible Wednesday night into Thursday. A wintry mix of precipitation and possibly accumulating snowfall.

DISCUSSION

Issued at 412 AM CST Sun Feb 22 2026

Upper level short wave #1 is passing over the state currently. A few flurries have been occurring with an area of stratus dropping south over parts of western/central Iowa. An associated surface boundary has brought cold advection and gusty northwest winds to the state. Short wave #2 will arrive today and will bring another round of cold advection to the region. While some very thin stratus, in addition the the more well formed stratus mentioned above, is now over Iowa, another broad area of clouds is moving south over central Minnesota and eastern North Dakota. These clouds are following the 900 mb flow, which is from around 350 degrees at 30 kts. That speed would place this area of clouds into northern Iowa at 12-13z. One forecast challenge today will be the residence time of these clouds and how far south it will reach. Much of the forecast guidance has this cloud layer eroding from west to east late this morning and into the afternoon. Trying to find the reason for this erosion within the models. Model guidance does have a fair amount of drying in the 800- 850 mb range but not within the current cloud layer. Also, despite the second short wave passage, there is not a significant subsidence signal in the wake of that system. Favor a more cloudy solution for today with this stratus layer stuck under the inversion and drying above this layer and the favorable steering flow. Some erosion may occur on the west edge but not to the extent suggested by most model guidance. Gusty northwest winds will persist much of the day with gusts of 25 to 35 mph expected. While the wind will diminish tonight, it will still be in the 8-13 mph range and combined with low temperatures in the single digits above and below zero, will produce wind chill values of 10 to 15 below zero.

The area with snow cover across Iowa will have a difficult time warming this week while the snow free areas may warm nicely on Tuesday anyway. Otherwise, tap on the brakes about this warming hype. Still having difficulty foreseeing how a significant warmup can occur over the snow area where there will be lower temperatures to begin with. The lower dew points along with the cooler temperatures will result in lower surface wet bulbs that won't be efficient at snow melt. A short wave will move across Minnesota and Wisconsin on Tuesday and will bring light snow chances to northeast Iowa. Monitoring the system for Wednesday night and Thursday as a more significant short wave moves through the state. This system may bring a wintry mix to the state and potentially more accumulating snowfall. The NBM is forecasting highs in the 40s and 50s on Friday. At this point, that is very optimistic at best. Final pondering thoughts in the day 6-10 range, why is the polar vortex shifting south into the western hemisphere?

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 536 AM CST Sun Feb 22 2026

MVFR stratus is the primary aviation focus during the period. Thin stratus that is not showing up well on satellite is currently moving across Iowa. A more well formed area of stratus is moving south across Minnesota. Timing and potential erosion on the western edge of that stratus as it arrives into Iowa leads to some uncertainly on extent and residence time at sites. KMCW/KALO will be impacted for a more prolonged period. Introduced a few hour period of MVFR stratus at other sites. Another round of stratus may arrive tonight. At this time, have only mentioned SCT025 at KDSM/KOTM and will continue to evaluate southward extent. Gusty northwest wind today will persist much of the period.

DMX WATCHES/WARNINGS/ADVISORIES

None.