textproduct: Des Moines

KEY MESSAGES

- Wintry precipitation continues to trend southward later today into early Monday, with only light snow amounts expected in far southern Iowa during this time.

- Light freezing drizzle may be possible in southern Iowa late tonight into Monday morning. Very little accumulation is expected, but any icing that can occur on roadways would impact travel conditions during the Monday morning commute.

- Milder into next week with several rounds of precipitation chances possible, mainly in the form of rain accompanied by thunder at times.

UPDATE

Issued at 217 AM CST Sun Mar 1 2026

Low stratus clouds have become entrenched over most of northern Iowa overnight, with some patches farther south/southwest as well, and have updated near-term temperatures to account for their effects on differential cooling. Later today into Monday, confidence continues to increase in a more southern solution for precipitation, with dry air entrainment from the large high pressure center to our northeast largely pushing precipitation down across Missouri. Have maintained the trend of moving POPs farther south - maintained low chances roughly south of Highway 92, but any chances of even 40% or greater are limited to only the far southern row of counties in Iowa. Accordingly, QPF is light with a strip of 0.1" only right near the state line, and less up toward Highway 34. However, while confidence is high that any precipitation that falls in Iowa will be limited to the south and will be light in accumulation, the confidence in type of precipitation that may occur is still relatively low. This afternoon and evening temperatures will be above freezing but the majority of forecast soundings favor light snow, if any precipitation occurs in Iowa at all, with the saturated layer extending up through the dendritic growth layer. However, late tonight into early Monday morning the saturation depth decreases and ice introduction may or may not shut off. With such shallow moisture and little to no lift in the cloud layer by that time there may simply be no precipitation Monday morning, but if it can occur then light freezing drizzle may be relatively more likely as the type. Have advertised this in the outgoing forecast, however, even if freezing drizzle does occur, any accumulation would be little to nothing, so unless icing can occur on any southern Iowa roads, any impacts should be minimal.

SHORT TERM /THROUGH MONDAY/

Issued at 237 PM CST Sat Feb 28 2026

Dry conditions across the greater majority of Iowa today, though cannot say the same just over the IA/MN border where a notable band of snow has been sliding east/southeastward through the day. The snow up in this area led to low visibilities under a mile, with accumulations of a few inches of more, but into northern Iowa, particularly in the CWA, only a few locations such as Mason City and Forest City saw only a dusting earlier this morning. Otherwise, the expectation is that the snow will remain out of forecast area for the rest of the day, which will overall lose its forcing through the rest of the afternoon and especially evening. Though remaining dry, cloud cover will hold on over portions of northern to eastern Iowa, slowly deteriorating as they gradually move south into Iowa by tonight. Regarding temperatures, temperatures have been slow to warm across the northern two thirds of the state, with values in the 20s to low 30s, whereas southern Iowa has warmed into the 40s to low 50s where sunny skies are more widespread, along with breezy northeast winds occasionally gusting up to 20-25 mph. Expected temps to warm just a bit more this afternoon, before falling near and just after sunset, along with decreasing winds as the PBL becomes more stable. Overnight lows are expected to fall into the teens to low 20s, warmest south.

Sunday looks to be on the dry side through the morning, though the system that has been well known over the last several days is still expected to arrive into the region into the afternoon, characterized by a mid-level shortwave trough over Nebraska/Kansas tracking eastward into Missouri and influencing parts of Iowa. With this feature comes some moisture return, which is largely focused over Missouri, thanks to the rather large area of surface high pressure further north that will continue to descend over the Great Lakes at the same time. Models continue to trend even more so on the drier side over the greater majority of Iowa, including the Euro which was much slower over the last several days in catching on to the intrusion of dry air that will spread over the state due to this high pressure over much of the region. With the bulk of moisture and isentropic forcing for ascent generally over Missouri Sunday afternoon to evening, the PoP trends have decreased even further with the current package, with any potential for at least some minor snow accumulations looking to largely originate over very far southern Iowa, then increasing in amounts southward through Missouri. Specifically, expecting up to a few tenths south of Highway 34, while further into central Iowa could occasionally see a few flurries as some flakes may overcome the dry low levels given some indication of more notable lift within the saturated DGZ, though with no expected accumulations.

While the mid-level saturation decreases across the region late Sunday into Monday morning, which indicates loss of ice introduction and therefore cutting out any lingering snowflake production, models indicate lingering low level saturation over portions of southern Iowa as the shortwave continues to gradually depart eastward, where this saturation paired with an least weak forcing in these area suggests a window of freezing rain/drizzle. The NAM is the most robust in this potential as it suggests low level saturation over 1km and a veering wind profile that would indicate turbulence to aid in increased particle interactions and thus better potential to see at least drizzle at the surface. Given uncertainty on the extent of lift to aid in more efficient icing potential from any freezing drizzle, have held off on any winter headlines at this time, but will be monitoring trends very closely. The important takeaway is that freezing drizzle is possible that could lead to at least a minor glaze of icing if this does setup over southern Iowa, so plan ahead on potential slick conditions into the Monday morning commute time. Conditions look to dry out at least briefly into the afternoon, but then a weak shortwave just ahead of a strengthening western CONUS trough looks to arrive into western Iowa Monday evening/Tuesday, bringing additional chances for precipitation.

LONG TERM /MONDAY NIGHT THROUGH SATURDAY/

Issued at 237 PM CST Sat Feb 28 2026

The weather pattern only becomes more active into the mid-week period as a rather robust frontal boundary with notable forcing lifts up into Iowa, which looks to come with warmer air and the potential for showers and thunderstorms. There are some notable differences on how the larger scale features responsible for this active pattern evolve into the latter portion of the work week, but looks to generally trend with additional chances for precipitation, while also warmer with highs in the 50s to 60s. More details to come during this time frame in the coming days.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 523 AM CST Sun Mar 1 2026

VFR conditions will prevail through the TAF period, with winds turning from NNE to ESE by this afternoon. Low clouds and MVFR or lower ceilings are forecast to spread into the area from the southwest on Monday morning, but will not reach the terminals until right around 12Z and thus will be addressed in later TAF issuances today.

DMX WATCHES/WARNINGS/ADVISORIES

None.