textproduct: Des Moines

KEY MESSAGES

- Cold this weekend with some flurry chances, especially Sunday. Gusty winds late tonight and Sunday.

- Cold wind chill values late tonight/Sunday morning north an again for much of the area late Sunday night/Monday morning.

- Warmer air begins to work in from the west through the middle of next week though will be tempered by the snow pack.

UPDATE

Issued at 408 AM CST Sat Feb 21 2026

Weak high pressure ridging is over the southwest half of Iowa early this morning. This morning's water vapor loop is showing an upper level PV anomaly over northeast Kansas which is lifting mid-level clouds into southern Iowa with bases AOA 7 kft. Kinematic forcing associated with the short wave energy is leading to modest vertical ascent within the cloud layer. The forecast challenge here is if any flurries can reach the surface. The mean layer flow below 700 mb or roughly 8 kft, consists of dry air from the north/northwest. Cloud bases below the 8 kft will occur due to hydrometeor loading sub cloud base leading to lower saturation but this process will not be very efficient with the dry air intrusion. There remains the potential for a few flurries but with impacts negligible, have left out of the forecast. Temperatures today may be impact more through, especially over the new snow pack region, where temperatures have fallen into the single digits early this morning. Any solar filtering from cloud cover today along with cold start this morning may hold temperatures in the teens in some areas, otherwise highs in the 20s elsewhere. Also monitoring stratus fragments that are settling south/southeast from southwest Minnesota to southern North Dakota. Not expecting much expansion areal wise with this stratus but the existing clouds could move into northwest and north central Iowa later today.

A couple of strong short waves will drop through the northwest flow with one arriving tonight and the other on Sunday. Both short waves will have an attendant boundary and cold advection along with gusty northwest winds. This will result in wind chill values of 10 to 20 below zero over northern Iowa Sunday morning and 10 to 15 below across much of the area Monday morning. There is a more broad area of stratus well upstream over Manitoba. These clouds should descend south and into parts of Iowa later tonight and into Sunday. Thermal profiles over northern Iowa will feature a deep layer of favorable dendritic growth temperatures. Stratus passing through these types of environments often produce flurries. Beyond Monday, the mid-level northwest flow breaks down into a more modified zonal flow. This is a warmer pattern for Iowa, however, low level moisture is mostly cut off from Iowa much of next week, meaning lower dew points. Snow pack over Iowa along with lower/sub freezing dew points do not promote a favorable warming setup, at least not to the extent models suggest. There may be a wide range in temperatures over the state between the snow pack and snow free areas.

DISCUSSION

Issued at 145 PM CST Fri Feb 20 2026

Skies are beginning to clear out over the area early this afternoon, revealing the swath of snowfall left in wake of yesterday's system. Amounts across the area were quite robust, with anywhere from 5 to 8 inches from western into central Iowa, then generally 8 to 12 inches from Interstate 35/Des Moines and northeast through Waterloo. Far northwestern Iowa between Waterloo and Mason City then up towards Decorah were the real winners though, with snowfall reports of ranging from 13 to 16 inches in a narrow swath. Satellite imagery this afternoon also shows the sharp cutoff on the northern edge of the band separating bare ground near Forest City and Algona, from the 6 to 12" of snow in Fort Dodge to Hampton.

Winds have diminished quite a bit from last night, but remain light to breezy out of the west northwest this afternoon. Skies will be clear through the afternoon and early evening, and winds will continue to diminish, which will be favorable for a few hours of efficient cooling after sunset. This is especially true over the snow pack, where air temperatures will cool quicker than those with bare ground. However, mid- and upper- level cloud cover from a second, weaker shortwave to our south will work in from the southwest tonight, as will a broad area of stratus dropping into northeastern Iowa. Both of these cloud decks will work to insulate the ground, preventing temperatures from completely plummeting in southwestern and northeastern Iowa. That said, there will still be areas that remain clear through most of the night. Clear skies, in combination with the fresh snowpack and the recent warmth swaying the NBM bias-correction, overnight lows are likely too warm. Therefore, have dropped the populated NBM temperatures tonight, primarily over the snow pack.

The aforementioned shortwave passing to our south does find enough moisture to produce some light snow over Kansas and Missouri tonight, but will experience drier low-level air in Iowa from the high pressure overhead. Depending on the model you look at, a brief snow shower does creep into southern Iowa, but these solutions appear to be outliers. If a shower were to make it into southern Iowa, it would likely be light with minimal impacts. Therefore, have left the forecast dry for this evening and will continue to monitor for any more robust snow showers.

Aside from the wave to our south overnight tonight, the forecast remains cold and dry through the weekend. Have maintained the trend of lowering temperatures a few degrees over the snowpack through the weekend while the NBM begins to get a better handle on temperatures in this colder regime. With the northerly surface flow persisting through Saturday and Sunday, highs in the 20s and lows in the single digits to teens will be common. The coldest night looks to Sunday night into Monday, as another push of surface high pressure fills in behind another upper level wave on Sunday, which will also bring breezy conditions during the day on Sunday. Assuming skies remain clear of any stratus Sunday night into Monday morning, the reinforcing push of cold air, clear skies and diminishing winds by early Monday will allow temperatures to approach zero and wind chills to fall below zero.

Temperatures remain cool on Monday, but relief looks to be on the way through the middle of next week, as 500 mb ridging develops overhead bringing warmer air into the state. The snowpack will limit how warm high temperatures can get during the day, but advecting warmer southerly air into the area will at least start to chip away at snow on the ground. The longevity of this warm air will be dependent on the path of a few waves showing up in the pattern through the middle of next week, which guidance is far from any agreement on at this range. For now, the main takeaway is cold temperatures continuing through the weekend with some potential melting into next week.

AVIATION /12Z TAFS THROUGH 12Z SUNDAY/

Issued at 538 AM CST Sat Feb 21 2026

VFR conditions today with mid to high level clouds passing across the state. Northwest winds will increase today with most sites having sustained wind 12 kts or greater by this afternoon. A cold front will move across the area tonight and will bring gusty northwest winds. In additional MVFR stratus will likely move into northern Iowa. Less certainty at KDSM/KOTM,therefore, only introduced SCT030 at those sites.

DMX WATCHES/WARNINGS/ADVISORIES

None.